Pre-Study on Marine-Completion at Scania Engine Assembly

DEGREE PROJECT IN MECHANICAL ENGINEERING, SECOND CYCLE, 30 CREDITS STOCKHOLM, SWEDEN 2021

Pre-study on Marine-completion at Scania Engine Assembly

ANDREAS YOUSEF

IVAN NAZAR HANNA

KTH ROYAL INSTITUTE OF TECHNOLOGY SCHOOL OF INDUSTRIAL ENGINEERING AND MANAGEMENT Pre-study on Marine-completion at Scania Engine Assembly

Supervisors, KTH: Ulf Olofsson Students, KTH: Ove Bayard Ivan Nazar Hanna Andreas Yousef Supervisors, Scania: Johan Ling Lauras Vinteris Andreas Eldelind

June 6, 2021

Master of Science Thesis TRITA-ITM-EX 2021:xyz

Pre-study on the Marine-completion at Scania Engine Assembly

Ivan Nazar Hanna Andreas Yousef Approved Examiner Supervisor Ulf Olofsson Ove Bayard Commissioner Contact person Scania Johan Ling Abstract This study has been conducted at Scania Engine Assembly, in particular in an production area that produces Marine Engines. Scania always strives for continuous improvement and the purpose of this study has been to create an overview of the production area Marine-completion, where the marine components are assembled. The goals were to create a current state analysis, propose a future state analysis and propose suggestions of solutions for improvement of Marine-completion. The research question was: How can the strategies for the current state analysis be chosen, used and analyzed in order to accomplish a successful current state analysis?. The research methodology in this study was conducted using qualitative and quantitative research strategies, where both primary and secondary data were collected. The theoretical framework was divided into four subsections: Production systems, project management, technical solutions of today and supporting literature for solutions. The main method of this study was collecting data. The data included layout of the production, assembly times, quality deviations, engine variant classifications, Value Stream Mapping, Safety, Health and Environment related deviations and costs. Based on the current state, a future state was developed. The results of the current state analysis was that there are a total of 20 main variants of marine engines which have different assembly times. The assembly time can vary from approximately 45 minutes to 3 hours and 35 minutes for straight engines and approximately 4 hours to 8 hours for V8 engines. The mean results from Value Stream Mapping concluded a distribution of 40 percentage Value Adding and 60 percentage Non-Value Adding, where the largest waste from Non-Value Adding activities was bringing parts. Most of the quality deviations were caused by the method, where the biggest problem was regarding "tool insufficiency". Safety, Health and Environment related deviations were identified, where the largest problems were "risk". The future state analysis ended up in three cases, which explains the possible savings and future states. The Failure Mode and Effects Analysis resulted in 7 failure modes, where "Engine-card missing tasks/parts" had the largest rating. The suggestion of solutions resulted in a new layout, new routines with the engine-cards with digital screens and some other smaller suggestions. This study concluded in three main suggestions of solutions about "New layout at Marine-completion ", "Digital screens at each station" and "Continuous update of engine cards", which resulted in three assignment directives that Scania can further work with in the future. Keywords: Assembly, Lean manufacturing, Marine Engine, Scania, SPS, TPS

Examensarbete TRITA-ITM-EX 2021:xyz

Förstudie på marinkompletteringen i Scanias motormontering

Ivan Nazar Hanna Andreas Yousef Godkänt Examinator Handledare Ulf Olofsson Ove Bayard Uppdragsgivare Kontaktperson Scania Johan Ling

Sammanfattning Detta arbete har utförts på ett produktionsområde i Scanias motormontering i Södertälje, Stockholm. Scania strävar alltid mot ständiga förbättringar och detta arbete uppfyller det genom syftet att skapa en kartläggning över produktionsområdet med fokus i förbättringar. Målen med detta arbete var att kartlägga nuläget i Marinkompletteringen samt skapa ett framtidsläge tillsammans med föreslagna förbättringsförslag. Den forskningsrelaterade frågeställningen för detta arbete var: Hur kan strategierna för nulägesanalysen väljas, användas och analyseras för att uppnå en lyckad nulägesanalys?. Metoden för litteraturstudien som utförts för detta arbete använde kvalititativa och kvantitiva forskningsmetoder där både primär och sekundärdata samlades. Det teoretiska ramverket var uppdelat i fyra delkapitel: Produktionssystem, projektledning, tekniska lösningar idag och stödjande litteratur för lösningar. Huvudmetoden för detta arbete var datainsamlingen som inkluderade aspekter som layout på området, monteringstider, kvalitetsavvikelser, motorvarianternas klassificering, värdeflödesanalys, avvikelser kopplat till säkerhet, hälsa, miljö och kostnader. Utifrån nulägesanalysen utvecklades framtidsläget fram. Resultaten från nulägesanalysen påvisade en total mängd av 20 olika huvudvarianter på marinmotorerna som monteras i marinkompletteringen med olika monteringstider. Monteringstiderna kunde sträcka sig mellan 45 minuter till tre timmar och 35 minuter för raka motorer och ungefär fyra till åtta timmar när det gäller V8 motorer. Medelvärdet på resultatet av värdeflödesanalysen resulterade i en fördelning av 40 procent värdeskapande tid och 60 procent icke-värdeskapande tid där det största slöseriet tillkom vid upphämtning av artikel. De flesta kvalitetsbristerna orsakades av metodiska fel där det mest förekommande metodiska felet var framkomlighet för verktyg. Bristerna kring säkerhet, hälsa och miljö identifierades och den mest förekommande bristen var gällande risker på arbetsplatsen. Analysen av framtidsläget resulterade i tre scenarion som vardera förklarar möjliga kostnadsbesparingar vid utfasning av olika icke-värdeskapande aktiviteter. Failure Mode and Effects Analysis som utfördes resulterade i sju feltyper varav "brist på information i motorkort" hade högst risktal. Rekommenderade åtgärder för Failure Mode and Effects Analysis resulterade i förslag om ny layout, nya rutiner gällande motorkort med digitala lösningar samt ett flertal mindre lösningar. De föreslagna lösningar som gavs till Scania i detta arbete var tre konkreta huvudförslag angående "ny layout på marinkompletteringen", "digitala skärmar på vardera station" och "kontinuerlig uppdatering av motorkort" vilket i sin tur resulterade i tre uppdragsdirektiv som Scania fortsatt kan jobba med i framtiden. Nyckelord: Lean, Marinmotor, Montering, Scania, SPS, TPS

Foreword

This Master thesis has been conducted by two students at KTH from two different Master programs, Engineering Design and Production Engineering and Management. The project has been executed at Scania CV AB, Sodertalje, Sweden. We are very thankful for having this opportunity to perform our Master thesis at a world leading company for transport solutions, Scania. We want to give special thanks to our manager and contact person Johan Ling, head of product engineering at Scania Engine Assembly, who always supported us in our project and thesis. We also want to give a special thanks to Andreas Eldelind, head of process engineering at Scania Engine assembly, for taking the responsibility from Johan Ling at the mid phase of the project. We also want to thank our supervisor Lauras Vinteris at Scania Process Engineering for the support and help during the project. We also wish to thank the workers at the production area marine-completion, the technican Aldo Lecaj, the two team leaders Ninos Melke and Elias Melke and all the other workers for answering our questions. We would like to express special thanks to our supervisors and program managers at Royal Institute of Technology, Ulf Olofsson and Ove Bayard, for all help, support and mentorship during the project.

Södertälje, Sweden, 31 May 2021 Södertälje, Sweden, 31 May 2021 Ivan Hanna Andreas Yousef

Nomenclature

Abbreviation Swedish English Description

A document that AD Uppdragsdirektiv Assignment directive describes an assignment

Straight Engine with D9/DC9/DI9 Motortyp Engine type 9 Liters and 5 cylinders

Straight Engine with D12/DC12/DI12 Motortyp Engine type 12 Liters and 6 cylinders

V8-Engine with D16/DC16/DI16/V8 Motortyp Engine type 16 Liters and 8 cylinders

A paper with speciﬁc - Motorkort Engine Card engine speciﬁcations

The production area for MK Marinkompletteringen Marine-Completion assembly of marine components

NVA Icke-värdeskapande Non-Value Adding A concept within VSM

A control process Q-Zon Kvalitetszon Quality-Zone after assembly at MK

A concept used at SPS SHE Säkerhet Hälsa och Miljö Safety Health and Environment and at deviation management

A speciﬁc production SPS Scanias Produktionssystem Scania Production System system based on TPS

A Transport Management TMS Transport system Transport Management System System for engines at Scania

The foundation for TPS Toyotas Produktionssystem Toyota Production System production systems

VA Värdeskapande Value Adding A concept within VSM

A method for mapping VSM Värdeﬂödesanalys Value Stream Mapping the value-adding activities

iii

Contents

1 Introduction 1 1.1 Background ...... 1 1.1.1 Scania ...... 1 1.1.2 Scania Engine Assembly ...... 1 1.1.3 Power Solutions and Marine-Completion ...... 2 1.2 Purpose and Goal ...... 3 1.3 Research Question ...... 3 1.4 Delimitation ...... 3 1.5 Methodology ...... 4 1.5.1 Qualitative Study ...... 4 1.5.2 Quantitative Study ...... 4 1.5.3 Research Strategy ...... 4 1.5.4 Research Design ...... 5 1.5.5 Reliability and Validity ...... 5

2 Theoretical Framework 7 2.1 Production Systems ...... 7 2.1.1 Toyota Production System ...... 7 2.1.2 Scania Production System ...... 9 2.2 Project Management ...... 11 2.2.1 Plan-Do-Check-Act ...... 11 2.2.2 Kaizen ...... 12 2.2.3 Gantt-Chart Tool ...... 12 2.3 Technical Solutions of Today ...... 13 2.3.1 Pick-To-Light ...... 13 2.3.2 Virtual & Augmented Reality ...... 13 2.4 Supporting Literature for Solutions ...... 14 2.4.1 Different types of assembly lines ...... 14 2.4.2 Failure Mode and Effects Analysis (FMEA) ...... 15 2.4.3 Value Stream Mapping (VSM) ...... 16 2.4.4 The Seven Wastes and the Four M´s ...... 17

3 Method 19 3.1 Method of Project Management ...... 19 3.1.1 Gantt Chart ...... 19 3.1.2 Risk Assessment ...... 19 3.2 Data Collection ...... 20 3.2.1 Variant Mapping ...... 20 3.2.2 Time Collection ...... 20 3.2.3 Quality Data ...... 20 3.3 Current State Analysis ...... 21 3.3.1 Layout ...... 21 3.3.2 Classiﬁcation of Variants ...... 22 3.3.3 Waste Analysis ...... 22 3.3.4 Value Stream Map ...... 22 3.3.5 Quality Analysis ...... 22

v 3.3.6 Safety, Health and Environment Analysis ...... 23 3.3.7 Cost Analysis ...... 23 3.4 Future State Analysis ...... 23 3.4.1 Revised Layout ...... 23 3.4.2 Future Value Stream Map ...... 24 3.4.3 Costs & Investments analysis ...... 24

4 Results 25 4.1 Current State Analysis ...... 25 4.1.1 Current Classiﬁcation of Variants ...... 25 4.1.2 Current Assembly Time ...... 26 4.1.3 Value Stream Mapping ...... 26 4.1.4 Current Quality and SHE ...... 29 4.1.5 Current Layout ...... 30 4.2 Future State Analysis ...... 31 4.2.1 VSM Cases for Future State ...... 31 4.2.2 Failure Mode and Effect Analysis ...... 31 4.3 Suggestions of Solutions ...... 32 4.3.1 New Layout ...... 32 4.3.2 New routines with engine-cards ...... 33 4.3.3 Other Suggestions of Solutions ...... 35

5 Discussion and Conclusion 37 5.1 Discussion ...... 37 5.1.1 Current State Analysis ...... 37 5.1.2 Future State Analysis ...... 38 5.1.3 Suggestions of Solutions ...... 40 5.2 Conclusion ...... 41 5.3 Reﬂections ...... 42 5.4 Future work ...... 42

Appendices 45 Appendix A: Gantt chart ...... 45 Appendix B: Risk Assessment ...... 46 Appendix C: Spagetti diagram ...... 47 Appendix D: Forms for reporting events ...... 50 Appendix E: Layout proposals ...... 54 Appendix F: VSM and NVA Distributions of timed engines ...... 57 Appendix G: Assignment Directive (AD) for future work ...... 60

vi List of Figures

1.1 TMS carrier in Final Assembly line ...... 2 2.1 Classic TPS House ...... 7 2.2 The Scania house ...... 9 2.3 PDCA Cycle ...... 11 2.4 Single-model assembly line ...... 14 2.5 Mixed-model assembly line ...... 14 2.6 Top row of a FMEA Matrix ...... 15 2.7 Occurrence Ranking ...... 15 2.8 Severity Ranking ...... 16 2.9 Detection Ranking ...... 16 2.10 5 steps of value stream mapping ...... 17 3.1 The four different phases in the planning of the project ...... 19 3.2 Quality categories tree ...... 21 4.1 Classiﬁcation of Variants tree ...... 25 4.2 Assembly Time of straight and V8 engines at MK ...... 26 4.3 Value Stream Mapping - Mean Value of three 6 cylinder marine engines 27 4.4 Value Stream Mapping - Mean Value of NVA distribution of the three 6 cylinder marine engines ...... 28 4.5 3M Quality distribution ...... 29 4.6 Method Quality distribution ...... 29 4.7 SHE distribution ...... 30 4.8 Layout of the assembly area at MK today ...... 30 4.9 FMEA with suggested measures ...... 32 4.10 New suggested layout - Hybrid layout for kitting parts ...... 32 4.11 Home page of the suggested digital screen ...... 33 4.12 Form for reporting downtime ...... 34 4.13 Suggested model for sequencing ...... 35

List of Tables

1 Mean assembly time of the three timed engines ...... 27 2 NVA abbreviation, name and description ...... 28

vii

1 Introduction

1.1 Background

This section is divided into three subsections about Scania, Scania Engine Assembly and Power Solutions and Marine-Completion. The idea is to give the reader an background of the company and the production area that is investigated.

1.1.1 Scania

Scania CV is a world leader when it comes to a wide range of transport solutions such as buses, trucks, engines and service of their products [1]. The company was founded 1891 in Sweden and has since then grown into the largest provider of transport solutions in over 100 countries [2]. The company employs 49 000 people in 100 different countries all over the world [3]. Over 15 000 of them are situated in Södertälje where they produce most of the whole trucks, buses, and engines for different applications such as industrial engines, marine engines, etc [4]. A manufacturing system needs coordination since it is a highly complex system. A company’s progress is highly dependent on a functional manufacturing system with a strive for continuous improvements. A great example of a structure in manufacturing is the Toyota Production System (TPS) and Lean philosophy. These strategies provides a structure for a manufacturing site covering all sections of a company. How- ever, strategies need to become adapted to fit a company’s structure in order to fulfil its purpose. Scania has its own system called Scania Production System (SPS). SPS is a strategy that Scania developed during the 90s. The system is inspired by the likes of TPS and Lean manufacturing. The difference between SPS and TPS is that the Scania Produc- tion System is adapted to fit the Swedish way. It is based on the regional consensus of values, principles and management in the nordic country [5, p. 2].

1.1.2 Scania Engine Assembly

This subsection is based on an internal source from Scania, which is unpublished. The production unit of Scania engines for Europe is located at building 150 in Soder- talje, Sweden. The facility produces both straight and V8 engines. There are two different types of straight engines, one with 5 cylinders and 9 liters and another one with 6 cylinders and 13 liters. The main customers for Scania Engine Assembly are trucks, buses, industrial and marine engines. The two straight engines are assembled at the same production line, which contains 10 different assembly areas. The ﬁrst 3 assembly areas is called "basic engine assembly" and contains the core components of the engine. The assembly has a stop-go motion, which means that the engine is stationary during the takt time and when the takt time is due, the engine moves to the next station. Furthermore, the last 7 assembly areas are refereed to "Final Assembly" and contains mostly external components. This assembly

1 line has a continuous movement with a system called TMS carrier which holds the engine and the movement almost never stops, see ﬁgure 1.1.

Figure 1.1: TMS carrier in Final Assembly line

1.1.3 Power Solutions and Marine-Completion

This subsection is based on an internal source from Scania, which is unpublished. Scania produced over 10 000 engines year 2019 for Power Solutions, which includes engines for industrial applications and marine engines. Industrial and Marine engines are variants of a standard engine which have several special components, therefore there is a designated area after the ﬁnal assembly line for assembly of these special components. The designated area is called "marine-completion" (MK) and after this assembly, the engines are transported to the testing area of the engine assembly and lastly to the painting of the engine. The assembly area MK consists of ﬁve workstations where marine and industrial engines are assembled. Four of them are for marine straight and V8 engines and one for industrial engines. Each of these workstations contains one worker who assembles all the tasks for the completion of the engine. Thereafter, the marine engines will go through a quality control where a worker examines every engine that passes through.

2 1.2 Purpose and Goal

The purpose of this project is to create an overview of the marine engine completion at the engine assembly in order to solidify the current state of the site. With the insights of the current state, a foundation will be created, thus providing the possibility to perform a future state analysis. The end purpose of this project is to conclude in a group of suggestions for decreasing the costs in MK. The goals of the project are:

• Create a current state analysis. • Propose a future state analysis. • Propose a group of suggestions of solutions

1.3 Research Question

The purpose of the research question in this project is to challenge the current state with a question regarding the subject’s normal situation. A question was raised regarding the relevancy of the tools for the current state analysis. Therefore, the research question was formulated as following:

• How can the strategies for the current state analysis be chosen, used and analyzed in order to accomplish a successful current state analysis?

1.4 Delimitation

The limitations of this project will consist of controls that are needed to secure the quality of this project. The main aspects of the limitations will be dependent on time, resources, pre-knowledge and the current state of the workplace with the crisis of COVID-19. The main limitations will be:

• The project will be completed within 20 weeks with an end date at 2021-06-04. • The project will only consider the marine engines at MK, therefore excluding industrial engines. • Only the most frequent variants will be analysed • The suggested solution will not include an increase of employees. • The current state analysis will only consider the key parameters such as the cycle times, wastes and scraps. It will also consist of an overview of the ﬂow in- cluding only the key aspects and will therefore exclude what is considered ex- cess information. • The suggested solution will not include a change to the assembly sequences nor value added assembly time. They will be considered as static parameters

3 1.5 Methodology

In order to to collect information sufﬁciently enough to create a decent structure for this report, a research methodology will be reviewed for the implementation. The research methodology for this project will be conducted using qualitative and quantitative research strategies. The collected data will however consist of both primary and secondary data.

1.5.1 Qualitative Study

The qualitative study will be conducted using in depth interviews as well as short dialogues with involved personnel revolving MK. The interviews will be structured around a certain topic with ﬂoating questions and answers. Thus providing a qualitative information extraction. Along with the interviews, observations of the site will be conducted. This will provide a primary source of information for an in depth understanding of certain characteristics of the problems and opportunities. The information extracted from observations will mainly be collected through an activity called go and see. This activity is performed with the help of a qualiﬁed employee which will give a tour on the site answering questions on demand. This will be performed both physi- cally and digitally. To sum up, the following points are included in the qualitative study: – Interviews with employees. – Observations. – On site "Go & See". – Digital "Go & See".

1.5.2 Quantitative Study

The quantitative study will be conducted using data extraction from both internal databases as well as on site data collection. The extraction of data from the internal database will consist of previously collected history from the site. This history will be selected for a suitable data collection. The on site data extraction will consist of direct collection of the data from the site. To summarize, the following points are included in the qualitative study: – Data collection from the cloud. – Data collection from the site.

1.5.3 Research Strategy

The chosen research strategy was Action Research, because of its practical characteristics. One important part of this study is the work at Scania and the ability to implement the results in reality at the company. This is also connected to SPS, where every- thing moves towards continuous improvement. Action Research is appropriate strategy because it should give instant feedback to the stakeholders [6]. A part of this study

4 has been to engage the managers of MK in different project meetings to ensure that this project will give value for the stakeholders. However, using this research strategy, the results will not be able to be generalized, it will be very speciﬁc for this case, for the production area MK.

1.5.4 Research Design

The research design has been chosen to be descriptive research with its framework because of the aim of describing the current state of the production area MK. Descriptive research is suitable because of the focus of answering where, what and how questions. Firstly the current state will be described and later-on the suggestion of solutions and lastly a discussion and analysis of the current state and the improvements. However, this research is not considered experimental. For example, the assembly time is only observed and measured, it has not been controlled or manipulated in any way, therefore not experimental. In addition, there is no hypothesis in this study. The purpose was only to observe, measure and describe the different parts of the production area MK.

1.5.5 Reliability and Validity

The concepts reliability and validity is often used in research that contains data. Re- liability refers to the consistency of the investigation tool used on many different oc- casions. Validity refers to the precision and accuracy of the quantitative study, in this case the precision and accuracy of the data. The reliability was raised to a higher level by using tools from Total Quality Manage- ment. The tools used in this project have been used many times before in the same environments and the results have been successful. In addition, many different sources have been used to ensure a higher level of reliability. Regarding quality data, classiﬁ- cation of variants and layout, the results should have a very high reliability. However, there are some parameters that have low reliability such as the assembly time between different workers and different variants. In any case, the results should be identical if repeated at the same production area, given the same tools. Therefore, the reliability is considered relatively high. The validity was raised by increasing the amount of data for the same assembly for example. Different sources was used and similar results was gained, which indicates a high validity. The assembly time was measured by the workers at MK and some engine types were validated by the Thesis Workers for this project and the same or close result was obtained. Overall, the validity is considered at a normal or high level, at least enough for the purpose of this project.

2 Theoretical Framework

2.1 Production Systems

2.1.1 Toyota Production System

The Toyota Production System was initiated at the end of the 40s when one of the founders of the system started to implement a JIT structure for Toyota [7, p. 68]. Since then TPS has grown into a well renowned name within manufacturing putting an example for other producers in the market. The structure that TPS is built on consists of principles such as JIT and Jidoka with a core focus on continuous improvements [8, p. 922].

Figure 2.1: Classic TPS House

In order to illustrate the TPS principles, a diagram will be used for demonstrating them in a house resembling figure. This diagram shows on the bottom four strategies illustrated as founding stones of the house (See figure 2.1). The founding stones starts with the bottom showing the Toyota Way philosophy going up a step to visual management. The last founding stone before the floor starts illustrates the strategy of Leveled Production or Heijunka. The flooring consists of the principle of Waste Reduction One of the most central parts of the TPS house is the Toyota Way Philosophy. Some of its principles are illustrated directly as a part of the house while the strategy itself is a block within the TPS house.

7 The Toyota Way philosophy consists of 14 principles [8, p. 923]:

1. "Base your management decisions on a long-term philosophy, even at the ex- pense of short-term ﬁnancial goals"

2. "Create continuous process ﬂow to bring problems to the surface"

3. "Use pull systems to avoid overproduction"

4. "Level out the workload (Heijunka)"

5. "Build a culture of stopping to ﬁx problems, to get quality right the ﬁrst time"

6. "Standardized tasks are the foundation for continuous improvement for employee empowerment"

7. "Use visual control so no problems are hidden"

8. "Use only reliable, thoroughly tested technology that serves your people and processes"

9. "Grow leaders who thoroughly understand the work, live the philosophy, and teach it to others"

10. "Develop exceptional people and teams who follow your company’s philosophy"

11. "Respect your extended network of partners and suppliers by challenging them and helping them improve"

12. "Go and see for yourself to thoroughly understand the situation (Genchi Gen- butsu)"

13. "Make decisions slowly by consensus, thoroughly considering all options; implement rapidly (Nemawashi)"

14. "Become a learning organization through relentless reﬂection (Hansei) and continuous improvement (Kaizen)"

These principles are central for the culture within Toyota. It is based on the book The Toyota Way and has been adapted into the company. What builds up these principles are four core principles called the 4P. These four core principles consists of philosophy, process, people and problem solving [9]. Visual management is illustrated in the TPS house as a block but it is included within the Toyota Way Philosophy. However it’s importance motivates its place at the house as a key component of the strategy. The strategy relates to the Toyota Way principle which encourages the use of visual control. The purpose of visual management is to achieve a transparency of issues such as waste, non-quality and disruptions in order to simplify the mapping of the problems. An example of a tool within visual management is the 5S programme. The programme consists of 5 practices; sort, straighten, shine, standardize and sustain [10, p. 67].

8 Stable and Standardized Processes puts an emphasis of using process control to keep the stability within the processes. This strategy is mainly used to reach an operational excellence [11]. The last block before the ﬂoor is about the Leveled Production which is a translation of the Japanese word Heijunka. Leveled production is also a part of the Toyota Way principle "Level Out the Workload (Heijunka)" which states to balance the production volume evenly and also balance the use of workers and utilities [9]. The ﬂooring of the TPS house consists of the Waste Reduction strategy. This strategy aims to strictly reduce wastes using Toyota and lean tools such as 5 Why’s, Genchi Genbutsu, Eyes for Waste and Problem solving [8, p. 922].

2.1.2 Scania Production System

This subsection is based on an internal source from Scania, which is unpublished. The company Scania has created its own production system with a collection of core principles. This production system is known as the Scania Production System (SPS). The production system has been implemented throughout Scania since the 1990s and has been continuously improved since then. Similarly to the Toyota Production system with its TPS house, Scania has come up with an adaptation the model with their own principles. This is illustrated below in ﬁgure 2.2.

Figure 2.2: The Scania house

9 The Scania house is a collection their core principles and is built similarly to how a house is built. Starting from bottom and working the way up until the roof. Illustrated in the figure 2.2, the figure represents three of the six core principles as building stones and the remaining three surrounds the house. The principles are represented as building stones are customer first, respect for the individual and elimination of waste. The remaining core principles that surrounds the house are determination, team spirit and integrity. Customer first is the left hand building stone which represents the value of engaging themselves with the customer. Scania provides their customer with a range of opportunities when it comes to product customization. The term customer spans from the end customer all the way to the internal customers within Scania. Respect for the individual is the central building stone of the Scania house and it represents the core value of treating each individual the same way themselves want to be treated. This principle gives the employees encouragement to develop and are supplied with the opportunity of education. Elimination of waste is the right hand building stone of the illustration and it represents the reduction of deviations against the desired state. Continuous improvements are emphasized in this value through challenging work structures in order to minimize and eliminate waste. Determination is illustrated below the Scania house and it describes the dedication within Scania to reach their pre-defined goals. This core principle emphasizes the understanding of working in systems at the same time as it is important to note the details. Team spirit is illustrated at the right hand side of the and it is emphasizing the co-operation in different teams and between teams within the company sharing a common goal. Integrity is illustrated at the left hand side of the Scania house and it represent the acknowledgement of the responsibility of being a large manufacturer. This core value realizes the necessity to take action in societal and environmental problem as a role model through Scania’s principles and values [12]. The next level that is illustrated in figure 2.2 is the principle of Leadership. The principle is based on the strive to be a learning organisation. Improving the work environment is emphasized in leadership within the Scania way. This is done by acknowledg- ing each individuals important role in the company and providing them with training. The block resembling the floor of the Scania house is the principle of the Normal situation, this principle suggest the stability of knowing what the intended state is. The benefit of having a well defined intended state gives a clear level of standardization and knowing what the expected results should be. The principle is built on six sub- principles: standardization, takt, leveled flow, balanced flow, visualization and real- time. The next part of the Scania house is the interior which symbolizes the Priorities of the Scania way. The priorities are Safety Health and Environment (SHE), quality, delivery and the costs. SHE is valued as the highest priority since the safety of the work environment is the most important aspect of manufacturing. The second highest priority is quality. Quality is essential for good relations with customers and is key for competi- tion. It is prioritized before delivery because of the value of not delivering any products that lacks quality. The third in the priorities is the delivery. The delivery should be in line with the demand of the customer. Therefore it is important to not deliver too late, nor to early. The fourth and last priority of this level is the cost. By prioritizing the cost it is aimed to reduce the level of costs while at the same time keeping the pro-

10 ductivity. The next level of the Scania house to be described is the left hand pillar Right from me. This value emphasizes the importance of responsibility in the workplace. Each employee needs to feel a responsibility to make sure that they don’t receive a faulty product, adds faults in the product, nor deliver a faulty product. The employees has the right to receive an intended state of the product and the obligation the deliver a correct product. The right hand pillar in the Scania house is the principle of Demand driven output. This principle suggests that no product should be manufactured unless it has a customer. In this way, wastes in the form of overproduction, inventory and idle time are reduced. The top of the Scania house which resembles a ceiling is the principle of Continuous improvements. By enforcing continuous improvements, the normal situation can be uplifted to further levels. The principle suggests that there is nothing that cannot be further improved.

2.2 Project Management

2.2.1 Plan-Do-Check-Act

Oftentimes, when working with projects with the aim of improvements there are risks of sub-optimizations and lack of follow up after implementation. In order to reduce these risks, models such as Plan-Do-Check-Act (PDCA) can be followed. PDCA is a tool for continuous improvements which consists of planning, doing, checking and action. These steps are iterated in a cycle thus creating a strategy of ensuring a desired result over time. The process and steps are illustrated in ﬁgure 2.3.

Figure 2.3: PDCA Cycle

Planning The planning phase consists of setting different goals and identifying methods in order to achieve the desired state. This phase can use activities such as brainstorming in order to collect knowledge over how to proceed. The purpose of this phase is to create a structure of how to conduct the project in order to reach the desired result [13].

11 Doing The "doing" phase consists of the actual implementation of the planned methods. This phase can use activities such as experimentation, data collection and interviews. The purpose of this phase is to gather enough information to use it for achieving the desired result [13]. Checking The "check" phase is the part where the implemented change is reviewed and evalu- ated in order to ensure that the cycle is headed towards the intended result. Activities within the phase can be such of audits of external stakeholders to receive an objective point of view [13]. Acting The "acting" stage is the last phase before the next iteration. This phase contains the process of ensuring the continuity of the cycle. It is the standardization of the previous steps so that the improvements are sustained [13]. These cycles can be used in different steps within a project management. It is common to consider a ﬁrst cycle of the PDCA as the initiation of an improvement and following up with the next cycles as the different stages of an improvement plan.

2.2.2 Kaizen

Kaizen which is another word of continuous improvements is a philosophy that emphasizes continual improvements as a culture for all aspects within human resources. As a strategy its aim is accumulate improvements in a systematic way in order to improve the organization’s competitiveness. The key parameters of improving the competitiveness for an organization are achieving higher quality, productivity and delivery times along with a decrease of costs [14].

2.2.3 Gantt-Chart Tool

The gantt-chart is considered as a classical tool in project management for planning and has been implemented in the way of managing projects in several companies. The tool is a visual representation of a schedule with a deﬁned time-frame. It can be used for several different project due to its ﬂexibility and simplistic approach [15, p. 578]. However, it is not the only project planning tool. There are other newer tools such as the Critical Path Method (CPM) and Program Evaluation and Review Technique (PERT). Although these newer methods has been presented along the years, the gantt- chart is still widely used. One reason for this is the versatility of the tool where it can be combined with CPM oftentimes [15, p. 579].

12 2.3 Technical Solutions of Today

2.3.1 Pick-To-Light

A manufacturing site that uses assembly technology when bringing value for the product will come in contact with different forms of order picking. Order picking is a con- ventional strategy when it comes to kitting the items for assembling them into a product. The items are picked from a central storage and distributed to the intended area of which the product will be assembled. Due to its complexity, it is usually done by human workers. This provides the risk of picking the wrong item due to human error. In order to minimize the human aspect within this error, along with time consumption of the task, technical solutions such as the pick-to-light system can be implemented [16, p. 133]. Pick to light is an already established tool within industries of today. The tool is a form of order picking technique where a light signal lights up the location of an item that needs to be picked. This is displayed on a monitor that speciﬁes the type, quantity and other characteristics regarding the item. The picker will then gather the items until all the light signals for the order are turned off [17, pp. 2260-2261].

2.3.2 Virtual & Augmented Reality

Virtual Reality (VR) and Augmented Reality (AR) are two technologies that creates or replicates a digital surrounding. The two applications differs however in the fact that VR supplies a fully digital environment while AR adds segments of a digital environment in the real world [18]. Augmented Reality puts layers upon real world environments and can be used in several different ways. It is capable of reading objects that are predetermined as for example numerical values on a paper and interpret it for different mathematical applications. It is also capable to simply display certain objects in relation to real-world view. AR can be applied through several different entities such as smart glasses and hand- held devices such as cell phones or tablets. Smart glasses can be divided into two categories, Optical see-through and Video see-through. The optical see-through provides the user with a display directly visually of the real-world environment while the video see-through gives the user a video captured real-world environment that is perceived in front of the user. This video perception is casted onto a display on the glasses that the user is wielding along with the intended AR application [18]. Virtual Reality on the other hand creates a fully virtual environment for the user’s visual and combined with headsets also the hearing. The technology uses a stereoscopic device to mount onto the head with a computer system that can project an environment that the user can navigate through [18].

13 2.4 Supporting Literature for Solutions

2.4.1 Different types of assembly lines

An assembly line is today a physical group of several stations where value adding activities are performed. These activities can be divided throughout the series of stations. The beneﬁt of dividing the workload through these stations is gaining a reduction of assembly time when it comes to mass production with a relatively constant input. However, depending on the distribution of time within the individual station, it could be counterproductive due to continuously increasing buffer quantities and increased slack time. Therefore, balancing the assembly line is required [19, p. 510]. In this analysis There will be two types of assembly line models; Single-model and Mixed-model assembly line. Single-model assembly line This type of assembly line is commonly used for non-varying products. Which suggests an assembly system without any variations of and within products. This is a sim- ple system that makes the line balancing go with ease. However, this does not mean that the line balancing wont follow a precedence diagram [20, p. 47].

Figure 2.4: Single-model assembly line

In recent years, the single model assembly lines due to its uniformity has been automated in most industries. This is since no variation often leads to a decreased interest from customers. Therefore, it is more common to use automated assembly rather than manual assembly [19, p. 512]. Mixed-model assembly line The mixed-model assembly line is applied when there are different varieties added for the product. This assembly line is ﬂexible and can attract a variety of customers since the products that are produced can have different characteristics. The total amount of different products are based on how the combinations of sets of parts for the product.

Figure 2.5: Mixed-model assembly line

14 The line balancing of this assembly line receives a higher amount of complexity than for example the single-model assembly line. This is due to the variation of the different products and their different cycle times. However, with the application of a ﬂexible workforce and decreased setups time, there are ways of combating this [21, p. 350]. The mixed-model assembly line can also be divided in two different systems. One is the mixed-model assembly line for make-to-stock and the other is the mixed-model for make-to-order [20, p. 57].

2.4.2 Failure Mode and Effects Analysis (FMEA)

Failure Mode and Effects Analysis is a versatile tool that can be applied in several different systems. The tool is commonly used within manufacturing plants in processes, safety, quality, logistics and even managerial aspects. It approaches the deviations within these field systematically, identifying the the different drivers in a specific risk and its future effects. FMEA when applied works systematically to find the root cause and the corrective actions of this cause [22, p. 1028].

Figure 2.6: Top row of a FMEA Matrix

There are three numerical values to ﬁll in for the FMEA matrix and that is the occurrence, severity and detection. These three combined multiplied will create a risk priority number (RPN). This number is a way of sorting the risks according to the highest RPN in order to prioritize the most severe, frequent and undetectable risk to manage it ﬁrst. The ranking of the three parameters, occurrence, severity and detection follows these tables [22, pp. 1028-1029].

Figure 2.7: Occurrence Ranking

15 Figure 2.8: Severity Ranking

Figure 2.9: Detection Ranking

2.4.3 Value Stream Mapping (VSM)

Value stream mapping is a tool that is used for determining the distribution and the amount of time between the value added activities and non-value added activities. The activities are of such which are performed for manufacturing a product [23, p. 446]. The purpose of performing a value stream mapping is to eliminate or decrease the non-value adding time and activities. The non-value adding activities are defined as activities that the customer is not willing to pay for. The value adding activities are however defined as activities that the customer is willing to pay for [24, p. 769]. The non-value adding activities can be further divided into two groups, non-value adding activities and non-value adding but necessary and indispensable. This division adds another level when it comes to prioritizing the elimination or reduction of the activities. It results in an order where the non-value adding activities should be eliminated before the non-value adding but necessary [25, p. 989]. Value stream mapping can worked with in five steps [25, p. 989]:

16 Figure 2.10: 5 steps of value stream mapping

2.4.4 The Seven Wastes and the Four M´s

Wastes can be classified in several different ways. One way of classifying wastes in industries is the four M’s(4M) method. 4M stands for material, man, machine and method. The 4M are commonly used as four branches in an Ishikawa diagram point- ing towards the waste. This can be applied when trying to find the root cause of a specific occurrence of waste. The wastes that are connected to material are for example defects in raw material, rework of the product, inventory holding and transportation. When it comes to human related wastes, activities such as movement, waiting, time for searching for objects and similar activities are considered. Machine related waste can be for example machine downtime and non-conformance. Lastly the method related wastes are the likes of lack of standards, lack of quality assurance, wrong setups, etc [26, p. 19]. Wastes can also be categorized according to TPS seven wastes. This classification cat- egorizes the wastes according to the following 7 points [26, p. 20]:

• Overproduction Overproduction is when a company produces more products than the customers demand or too early, which is a waste.

• Inventory Inventory is a waste because the materials and products are not processed, therefore a waste for the production because no value is being adding to it.

• Motion Motion is a waste because it refers to unnecessary movement of the workers.

17 • Defectiveness Products or services that do not fulﬁl the requirements are identiﬁed as defect products or services. Defectiveness often leads to rework, which is a waste in the production.

• Transportation This refers to unnecessary transportation of products between processes or within an production are. This is deﬁnitely a waste because of no value adding.

• Over-processing Over-processing implies that the quality or work done is excessive, which is a waste because it is above the customers demand.

• Waiting Waiting is a waste because of time spent only waiting before moving on to the next step in the process. Time is a high cost in production and waiting does not contribute to any value for the customer.

18 3 Method

3.1 Method of Project Management

A traditional project management was chosen in this project because of the better fit. The organizational structure was linear and the project was divided into four large phases. The first phase was initiation and theoretical background. In this phase, the literature study and background was conducted. The second phase was Implementa- tion and Method. This is where the work began with collecting data and documenting some results. The third phase was Results and Analysis, where the results from data collection was processed and analyzed. The fourth and last phase was the End Phase. At this stage, the work at the production area MK was completed and the focus was instead on the report, the presentations and completing other documentation. Between the phases, a gate meeting was hold together with the supervisor and the manager at Scania to identify eventual problems or delays in activities. The four phases are illustrated in figure 3.1.

Figure 3.1: The four different phases in the planning of the project

3.1.1 Gantt Chart

To be able to follow up the planning, a gantt chart was used. The Gantt chart contained all four phases, all activities of the project, responsibilities and deadlines. The Gantt chart was used and updated every week together with the supervisor and the manager of Scania. The full scale Gantt chart of this project can be found in Appendix A.

3.1.2 Risk Assessment

A risk assessment was conducted in the beginning of the project, which can be found in Appendix B. The risk assessment was important to identify eventual risks in the project. One of the largest risk with the highest risk rating was delays in necessary equipment, e.g. computers and Ofﬁce 365. Many hours was spent in the beginning of the project to get the technical issues to work, which was necessary to be able to collect data. There was a total of 11 identiﬁed risks, which can be found more in detail in Appendix B. This chapter is describing the method of the data collection. Different data has been collected in different ways, which are described in the different subsections.

19 3.2 Data Collection

This chapter is describing the method of the data collection. Different data has been collected in different ways, which are described in the different subsections.

3.2.1 Variant Mapping

Since the variants of Marine engines were separately defined from the rest of the assembly, it was essential to differentiate these. The variant mapping consisted of gathering data using both quantitative and qualitative data in order for the differentiation. The quantitative data that was gathered consisted mostly of extraction of different variants through the internal data base. While the qualitative data was collected through interviews with the workers by their experience with the variants. By performing the collection of information in this manner, a reliable way of gathering the data was achieved. Also, the data was validated by combining the internal database with the information from the workers. The first step of mapping the variants was to create a dialogue with the workers in order to interpret how a motor variant is defined. Thereafter the variant names that were provided by the workers was compared with the naming within internal data.

3.2.2 Time Collection

The time of the assembly for different engines were collected by the workers inter- nally. This data was part of a daily routine where the worker clocked the start and stop times of the engine assembly. However, these statistics were in a ﬁle that collected several aspects such as non-quality issues, risks and other parameters. Therefore, the data was collected in a separate ﬁle independently in this project from the other data. This provided a more structured collection where key parameters such as meantime and frequency of variants were extracted.

3.2.3 Quality Data

The method used to collect data for the quality deviations were done by Scania’s internal systems, tools and routines. One computer-based system that was used is called FRAS. Daily reports from the production department was also used. FRAS is a computer-based system for documentation of all projects at Scania. This system was used in order to collect data regarding quality deviations. There were different categories of opened projects such as ﬁeld quality, production related, exception from requirement etc. When searching for relevant information, open projects related to production were ﬁltered. Daily reports from the production unit was used to collect daily deviations at the area MK. These reports were stored in Scania folder system. The method was to read the notations and comment from the production unit and identify a category and the reason of every deviation to be able to get the results.

20 The quality data was divided in different categories in different levels. In the first level, the quality was divided in three categories; internal, partly internal and external quality. External refers to not production related reasons, for example errors from sup- plier or from another area than MK. Internal are directly production related and related to the area MK. Partly internal are for example part defect or missing parts. More- over, in the second level, the quality deviations were divided into 3M, which stands for Man (human-cased deviations), Method and Machine deviations. However, these categories were carefully selected. The last level of categories was done because of the many deviations in the Method category. Therefore, the method was divided into four categories; engine-card error, design specification, tool insufficiency or assembly difficulty and lastly carrier programming. Figure 3.2 below shows the different categories in different levels.

Figure 3.2: Quality categories tree

3.3 Current State Analysis

The current state analysis is described in this chapter. The current state is divided into 7 different subtopics which are described in detail in this section.

3.3.1 Layout

The layout was created from previously made internal layouts of MK. These layouts were created using 3D factory layout programs. However, for a more simpliﬁed point of view of MK, a new layout was created. This layout is updated with the recent changes to the area, changes such as moving the material rack from the centre to the edges of the area.

21 3.3.2 Classiﬁcation of Variants

The classification of variants could be done in many different ways. The chosen classification was done together with the team leaders of the production area MK. The classification was made based on the components of the engine and assembly time. For example, if an engine had many electrical components it would be the electric variant. However, there is another classification of variants that is based on the engine card, which is the engine abbreviation. It is based on the different tasks needed to be done in the assembly area. This variant classification was used more in the time data collection. The second classification was used in parallel with the first classification in this project.

3.3.3 Waste Analysis

The waste analysis was based on the 7 wastes and the four M:s described in the The- oretical Framework. However, the four M:s was a useful method for categorizing the deviations, but in this project one of the M, material, was removed. Regarding one of the 7 wastes, motion, a method was used during the time data collection which is called Spaghetti Diagram. This method was used to identify the motion of the assembler when assembling the engine at one speciﬁc station. The waste analysis was connected to the value stream mapping, where many of the wastes were addressed to a speciﬁc time of the assembly time. However, this topic is described more in detail in the next subsection.

3.3.4 Value Stream Map

The value stream map was created with the provided data from the activities of time collection, waste analysis and on-field investigation. Due to limitations it was decided to focus on the three most frequent variants. The time collection contributed to the total time of the assembly excluding the load- ing and offloading. This total time provided the span to fit in the corresponding value added and non-value added time along with the time of waste. The on-field investigation was conducted using a time-keeping of the three corresponding variants to compare with the overall time that was collected through the internal database. For the detailed analysis of the three engine variants, timing was conducted collecting value added time and non-value added time. The value added time was defined as time used for adding parts to the product that would bring value to the customer. For simplification the value added time would consist of parts that would come through to the end customer. The non-value added time consisted of several categories

3.3.5 Quality Analysis

The quality analysis was based on the data given from the data collection. The method used to examine and analyze the quality deviations is FMEA. The goal of FMEA is to

22 identify potential failure modes and in this project, a worksheet in Excel was used to document all failures connected to quality in the area MK. The Failure Mode and Effects Analysis was performed together with involved personnel within MK. The process of conducting the analysis was performed by reviewing each column of the FMEA matrix based on the failure mode. Failure Mode The failure mode was determined through reviewing the daily reports and internal quality data, ﬁnding the most occurring and extensive failure mode. To validate the failure mode, discussions with team leaders and workers were conducted to check the relevancy of each failure mode. Failure Cause & Effect The failure causes and effects were determined through reviewing the internal quality data for the cause and effect of each failure mode. This was discussed with the sites quality employees for validation. Ranking The ranking was based on a scientiﬁc paper that was reviewed in the theoretical framework (See section 2.4.2). These values were determined together with an experienced employee within quality at MK.

3.3.6 Safety, Health and Environment Analysis

The Safety, Health and Environment (SHE) analysis was based on observations and the data from daily reports. The observations was done by the workers at the production area MK and the thesis workers. Several Go & See was arranged and some observations were documented in an Excel sheet. However, it was difficult to find data connected to SHE with occurrence. The SHE deviations was divided into four parts, ergonomic, environment, risk and parts on floor. These categories were decided by the thesis workers together with the workers at the production area MK.

3.3.7 Cost Analysis

The costs were determined using a standardized cost calculation provided by the company for each minute that passes within MK. This cost calculation includes aspects such as workforce, plant area, and delay costs. This data multiplied with the waste time for one engine, that was achieved through the value stream mapping, provided a cost for that speciﬁc engine.

3.4 Future State Analysis

3.4.1 Revised Layout

The revised layout was continuously engineered throughout the data collection and the interpretation of the data. Based of the different cases that was experimented, the lay-

23 out was adjusted to adapt the different proposed changes. Several layouts were mod- eled through brainstorming activities based on the current state of the layout. The proposed layouts were processed through a semi-workshop involving affected personnel into a single proposed layout.

3.4.2 Future Value Stream Map

The future value stream map was proposed based on the current state together with different cases of future changes. The experiments consisted of subtracting different activities based on possible real time changes of the site.

3.4.3 Costs & Investments analysis

The costs and investments were based on the construction of different cases within the value stream mapping. These costs were gathered through a pre-calculated cost per minute for the site and further processed with the time consumption of the non- value adding activities. These costs were compared to the costs of investing in different equipment and re-arrangements within the site.

24 4 Results

4.1 Current State Analysis

4.1.1 Current Classiﬁcation of Variants

The variants of marine engines at MK were ﬁrstly divided into two variants, Straight engines and V8 engines. There are two different types of straight engines depending on the number of cylinders and the volume of the total cylinders. There are 5 and 6 cylinders for straight and 8 cylinders for the V8 variant, which results in three different main variants. Furthermore, each of the cylinder variants has a number of variants depending on the components needed to be assembled. The different variants and the name of the variants can be seen in ﬁgure 4.1.

Figure 4.1: Classiﬁcation of Variants tree

25 There are in total 20 different main variants and each variant has its own assembly time which can differ a lot between the variants. These 20 main variants are most frequent and only these are analyzed in this project.

4.1.2 Current Assembly Time

The assembly time of each variant has been collected and documented at the company. A histogram of the Assembly time of different variants can be seen in ﬁgure 4.2. To the left, the assembly time for 5 and 6 cylinders can be found and to the right the assembly time for 8 cylinders.

Figure 4.2: Assembly Time of straight and V8 engines at MK

In total, a volume of 81 engines were clocked and analysed. The range regarding assembly time was from approximately 45 minutes to approximately 3 hours and 35 minutes for the straight engines. The range for V8 engines was from approximately 3 hours and 56 minutes to approximately 7 hours and 50 minutes.

4.1.3 Value Stream Mapping

The results of the value stream mapping can be seen in Appendix F and the mean value can be seen as a pie chart in ﬁgure 4.3. The value adding activities took 40% of the total assembly time and the rest was non value adding, which results in 60% NVA. The mean value was based on three engines, where two of them were standard variant and one was electric classiﬁcation.

26 Figure 4.3: Value Stream Mapping - Mean Value of three 6 cylinder marine engines

Moreover, the mean value adding time, non-value adding time and total assembly time can be found in table 1. The mean total assembly time of the three timed 6 cylinder marine engines were 1 hour, 27 minutes and 9 seconds.

Table 1: Mean assembly time of the three timed engines Description Mean Time VA (Mean) 34:36 NVA (Mean) 52:33 Total assembly time (Mean) 01:27:09

However, the wastes of the assembly in the category NVA needed to be divided into speciﬁc wastes, therefore a new pie chart was created to visualize the NVA distribution. The different NVA distributions for each engine can be found in Appendix F and the mean value of NVA Distribution of the three engines can be seen in ﬁgure 4.4.

27 Figure 4.4: Value Stream Mapping - Mean Value of NVA distribution of the three 6 cylinder marine engines

The different abbreviation descriptions in the NVA distribution can be seen in table 2.

Table 2: NVA abbreviation, name and description

Abbreviation Name Description HA Bring parts Worker brings parts to the assembly area Worker collets parts from the shelf to the K "Kitting" - Order Picking assembly area Docking the Engine in the beginning of the D Docking Engine assembly from pallet to Engine Carrier Worker brings a tool from shelf to the HV Bring Tool assembly area LMK Reading Engine Card Worker reads the engine card R Motion Worker moves within the production area MK Rotation, lifting or transportation of the LB Engine Carrier Engine-Carrier during assembly LV Lifting Tool Worker uses a lifting tool for heavy components Worker walkes to a computer and prints UMK Printing of Engine Card the Engine Card HV/HA Bring Tool + Part Worker brings a tool and a part simultaneously Worker uses forklift to move pallet in the T Forklift production area MK Worker transport the engine from buffer TM Engine Transportation to assembly area Worker assembles loop materials such A Adapter for Engine Test as an adapter for testing the engine Ö Other Other NVA activities than listed above

However, as seen in ﬁgure 4.4, the biggest section of the pie chart is "HA". This contributes to 37% of the total NVA. The second biggest section is "K", which contributes to 13% of the total NVA. The third biggest section was "D" with 9% of the total NVA. These three biggest sections together cover more than half of the NVA wastes, therefore the focus should be on these three points in future solutions.

28 Many of the NVA activities were connected to the waste "motion" of the 7 wastes. The spagetti diagram of the three engines that were clocked can be found in Appendix C. The results of the spagetti diagram is that there is a lot of motion around the engine, but also long distance motion such as transportation, bringing parts, printing the engine-card or docking of the engine to the carrier.

4.1.4 Current Quality and SHE

The results of the quality deviations in the current state analysis was divided into three main sections and the biggest section of the pie chart was "method", as seen in ﬁgure 4.5. This implicates that the largest cause is the process and method of the assembly.

Figure 4.5: 3M Quality distribution

Furthermore, in figure 4.6 the distribution of the quality deviations connected to the method section is shown. However, the biggest section is the tool insufficiency and assembly difficulty with 41%. The second section of the pie chart was errors in the Engine-card. The third cause was design specification, where the product was not according to the design specification or the other way around. These three sections cor- responds to 96% of all deviations under the category "Method".

Figure 4.6: Method Quality distribution

The results from SHE deviations can be seen in ﬁgure 4.7. The largest section is risks and the second largest is ergonomy. The other two sections rarely occurs. In general, there were not a lot of SHE deviation at the production area MK.

29 Figure 4.7: SHE distribution

4.1.5 Current Layout

The current state of layout can be found in figure 4.8. To the left, there are four buffer spaces, where the workers from logistic deliver unassembled engines to MK by forklifts. In the middle, there are five assembly stations, two stations for straight engines, two stations for V8 engines and one station for Quick industrial engines. At the top and bottom, there are shelves for parts that will be assembled on the engines. The green boxes at the bottom are spaces for finished engines.

Figure 4.8: Layout of the assembly area at MK today

30 4.2 Future State Analysis

4.2.1 VSM Cases for Future State

Case 1 phase out the order picking to logistics The first case for a future state is outsourcing the order picking for the logistics to han- dle. This case would conclude in an estimated saving of 6 minutes and 48 seconds per standard five and six cylinder engines. This is calculated based on the mean value for order picking the value stream mapping performed. Case 2 phase out engine docking with a conveyor The second case for the future state is conceptual of replacing the engine carriers with a conveyor for product handling. This would replace the necessity of docking the engine onto a carrier. The total estimated saving of phasing out the docking would conclude in a decrease of approximately 5 minutes and 4 seconds per standard five and six cylinder engines. Case 3 use independent screens at each station The third case for the future state is implementing digital screens for each station in MK. This would replace the printing of the engine card as it is for the current state. The engine cards would for this case be used digitally and therefore will eliminate the time for printing the engine card. By implementing this case, there would be a decrease of 1 minute and 17 seconds per standard five and six cylinder engines which alone would save 1 488 613 kr per year based on internal calculations.

4.2.2 Failure Mode and Effect Analysis

The Failure Mode and Effects analysis resulted in a matrix that concluded in 4 major failure modes that were in need of improvements. The most emergent failure mode was when the engine-card is missing some of the tasks or parts. The risk priority number of this failure mode was 392 which is the highest in this analysis. The suggested measure for both of the engine card related failure mode is to use real time communication with the product engineer for continuous update and improvements of the engine cards. Design error was the failure mode with the second highest risk priority number with a value of 252. The suggested measure for this failure mode is to update the drawing speciﬁcations so that it can represent the real product more accurately. Tool insufﬁciency was regarded as the third to prioritize based of its risk priority number at 224. The suggested measure was determined by this project to invest in new quality assured tools.

31 Figure 4.9: FMEA with suggested measures

4.3 Suggestions of Solutions

4.3.1 New Layout

During the project, many different layout suggestions were generated. A combined and improved layout suggestion was created after discussion with the managers for the production area, the suggestion can be seen in ﬁgure 4.10. Other layout suggestions can be found in Appendix E.

Figure 4.10: New suggested layout - Hybrid layout for kitting parts

32 The idea is that this layout is ﬂexible because of its layout, therefore it can be used as usual at MK that each station assembles the whole engine. In contrast, it could also be used as three straight stations after each other, where some tasks of an engine can be done in station 1 and then the engine can be transported to station 2 for other tasks assembly. This solution can be applied in combination with the solution "optimization of assembly sequence". The concept is to have a disconnected role at the top of the ﬁgure where a worker from assembly or logistics only focuses on preparing the parts for each engine. The worker will follow the engine card, pick the correct parts and place them on a track with rollers, thereby the parts will be placed at the right place, at the right time, in other words the concept Just In Time is applied, for station 1, 2 and 3 for the worker at MK that will assemble the parts on the engine.

4.3.2 New routines with engine-cards

The solutions regarding new routines with the engine cards concluded in two concrete suggestions. The solutions consisted of a suggested model for a digital handling for the engine cards and an initiation of a project regarding the continuous update of engine cards for MK. Digital screens at each station The solution of implementing digital screens at each station would include a system that is already implemented in other sections in Scania today. The digital screens would have the capability of displaying the engine card instead of the normal situation of today where it is printed onto a paper. A conceptual model for what it is to be displayed on these screen is proposed. The proposed layout of the model consist of a home page (see ﬁgure 4.11) that includes links for reporting events such as SHE, deviations, downtime and wastes. The remaining links consists of an andon button along with a list of the upcoming engines to assemble and initiating the next engine.

Figure 4.11: Home page of the suggested digital screen

33 The "list of today’s engines" button would provide the user with the upcoming engines and their current location in real-time conceptually. This would help the user managing the time for the day, thus relieving unnecessary misconceptions. The "Andon/TL" button would create an alert for andon to intervene in the assembly. The next button "Start assembly of the next engine" will bring the user to a page for the engine to assemble. The page would show PDF file of the engine card. By replacing the engine cards in paper with a digital PDF file, the time of printing the engine card would be eliminated as investigated in case 3 section 4.2.1. The buttons for reporting the events will bring the user to different forms based on the event. In figure 4.12, a form is illustrated where the user would put in different parameters. The parameters consists of name of the worker, the identification of the engine (PopID), date and time for the event, the type of error that lead to the downtime, time taken for the event, short description and what station this event occurred in. When the form is filled and registered, the system will export the data into an excel sheet with the inserted parameters.

Figure 4.12: Form for reporting downtime

The remaining forms for SHE, deviations and wastes can be found in Appendix D. Continuous update of engine cards The second suggested solution contains of a proposal for a future project regarding the update of the engine cards for MK. The update would include following points:

• Updating the assembly sequence with the best practice by involving experienced workers • Update all the torque values according to the speciﬁcations

In order to initiate a process of continuous updates regarding the engine cards, a pre- study will be required. The main aspects that the study must consist of are a precedence diagram, analysis of material positioning and the relationship between carrier

34 position and precedence of the assembly tasks. A recommended pre-condition for this project is to implement the system of digital engine cards in order for the user to have a real-time communication with the product engineer. This real-communication will be useful for real-time feedback when the engine card is non-conforming. .

4.3.3 Other Suggestions of Solutions

Optimization of assembly sequence A suggestion regarding the assembly sequence was reviewed. This suggestion would result in a new sequencing strategy where the different tasks of the engine would be performed based on the certain angle and position of which the carrier would be situated in.

Figure 4.13: Suggested model for sequencing

This assembly sequencing system would simplify the assembly training through standardized work routines. This sequencing method would reduce the re-positioning time of the engine carrier which would conclude in shorter assembly times. Multi-purpose sockets Multi-purposed sockets were suggested as substitute of the sockets that are in use in MK today. The purpose of this suggestion is to reduce the changeover time of the screwdrivers by using a single sockets that can ﬁt different screws and bolts. Over-head light signals combined with pick-to-light The over-head light signals would function similarly to the technical solution "pick-to- light" but instead of a solution for order picking, the over-head light signals would be an aid for assembly. The system is intended to light up certain spots on the engine to indicate were the next task would be situated. This would provide the assembly worker with a clear work in- struction. Combining the over-head light signals with pick-to-light would add a structure for the gathering of parts for the engine to assemble. The system would work in the following steps:

1. Initiate with scanning the engine card

2. Initiates pick-to-light system where the worker gathers the parts for the assembly

3. When all the lights in the PtL system are shut down next task lights up

35 4. Worker assembles next task

5. When done the worker uses a display to continue to next task

6. Next tasks over-head light lit

7. Iterate steps 4-6 until all the tasks are completed

Enable scheduling techniques for reducing risk of lateness This solution is focused on reducing amount of late engines. Techniques such as earliest- due-date (EDD) can be implemented since the site is not constrained by the ﬁrst-in- ﬁrst-out (FIFO) rule. This would include a restructure of the scheduling system for the engines in only one part of the overall assembly.

36 5 Discussion and Conclusion

5.1 Discussion

5.1.1 Current State Analysis

As mentioned before, there are many different ways of dividing the variants and there are advantages and disadvantages with the chosen classification of variants. One advantage is that the production workers at MK are very familiar with the variant names and definition, but on the other hand the other functionalities such as engineers, logistics and planning employees can not understand the production classification, which is an disadvantage. The reason is because other functionalities uses another type of variant mapping with codes. The assembly time and parts assembled for each variant is an important factor to consider when dividing the variants and the variants are not robust in assembly time and components. There is a minor difference in various engines with the same classification in both assembly time and components assembled. For example, two engines from the same variant "Large Turbo" can have different total assembly time, different number of components and different tasks as well. However, the assembly time, components and tasks are very close to the same. Therefore, a type of assembly time can be set for each variant with an error that is tolerated because of the variance. Regarding assembly time, the number of data collected (81) is appropriate and enough for the purpose of this project. Therefore, the period of collecting data between Jan- uary to April is considered enough. It was very clear seeing the division of variants in the first level, that all straight engines have close assembly time and the V8 engines have much greater assembly time. This means that the straight engines have a potential to create a sort of own assembly line, but it is almost impossible to have one assembly line for both straight and V8 engines because of the huge range in assembly time. One weakness of this analysis is the method of measuring the assembly time by the workers at MK. The method for measuring the assembly time lacked in robust- ness, there was no clear routine on how to measure the time. However, this assembly time was validated in this project as a sample test, where three engines were measured and compared with the measurement of the workers at MK, and therefore considered reliable enough for the purpose. By all means, it is important to have in mind the human errors from this collected data. One other factor to consider is the difference in assembly time between the different workers, therefore a mean assembly time was calculated. The VSM was performed on three engines, with the same or similar variant. Two of them had the same variant and the third was different variant, but all of them were DC9. The VSM analysis was difficult to perform for this application because of the long assembly time, and at the same time trying to keep the focus on every activity to determine if the activity is VA or NVA. Because of the difficulties and time- consuming, the VSM analysis was only performed on three engines, which is not optimal when discussing statistics, reliability and validity. However, the performed VSM gave a very good insight of where the largest wastes can be found and where to keep the focus when identifying suggestions of solutions. It has been noticed that the NVA-activities have a mean value of 60%, which is a very good identified parameter

37 to work with, because of Scania’s main goal Continuous improvement from SPS. On the other hand, it is a negative number because it represents that the waste are more than the value-adding in the production area MK. There was a difficulty in dividing the different NVA-activities, therefore there is definitely an error in the distribution of NVA. There was overlapping between different activities, which was difficult to separate in some cases. One example was the difference between HA, HV and motion, because sometimes the worker could walk long distances to bring a part and also bring a tool on the way. However, the benefit of the NVA distribution is that this is the first time it has been done in the production area MK, which gives an incredible picture of the waste distribution and importance for future development of the production of Marine engines. The results of the quality deviations were divided into 3M instead of 4M because the fourth M, material, is not suitable in the production. There was no deviation connected to the material, such as defect in the material, therefore the material classification was excluded. The largest section of the pie chart was further analyzed because of its big portion of the total deviations. The different deviations was partly taken from the daily report, and there is a risk that the same deviation has been reported several days, which can give a misleading picture of the distribution in the results. However, all non-quality deviations related to Method was frequent deviations, and for this reason all deviations related to Method are important to consider when discussing suggestion of solutions. The SHE distribution can be seen as confused, because some of the SHE deviations are specific such as parts on floor, while other SHE deviations are very general such as Risk. This data was collected from the daily reports and therefore difficult to work with, because the workers that reported them easily forget about what risk it is. However, the SHE pie chart gave an acceptable overview of SHE deviations, which is considered as low importance because of the low severity. Concerning the current state of today’s layout at the production area MK, a 2D-model was conducted. The 2D-model does not represent the real layout because many things are missing, such as computers, places for the workers, tools, carriers, forklifts and so on. The 2D-figure does not have the correct scale either, it is only supposed to compare an overview from current layout compared with future layout. As stated in the introduction, the research question was formulated as such: "How can the strategies for the current state analysis be chosen, used and analyzed in order to accomplish a successful current state analysis?". The research question has been an- swered indirectly during the analysis through implementation of the strategies that were used. Examples of strategies that were used for the current state analysis were variant classification, VSM, layout modelling, quality analysis, etc. Considering the result of these strategies, it can be concluded that they were successful when providing ground for the suggested solutions.

5.1.2 Future State Analysis

The results from conducting the future state analysis gave insights to the pre-deﬁned problems of MK. When it came to experimenting on different cases for the value stream map, each case motivated some form of initiation of further investigation.

38 The first case which suggested that the order picking would be outsourced to logistics contained both pros and cons. The pros of outsourcing the order picking is firstly the reduction of non-value adding time. By reducing the non-value added time, the costs will be reduced significantly. However other aspects that are less measurable are also counted as pros. For example, the simplification of the work tasks is a clear benefit for the workers by eliminating the order picking. Since the order picking requires complex movement routes for the worker. This simplification for the worker can result in a more accurate time collection of the assembly time since the order picking could vary depending on the experience level of each worker. The cons of phasing out the order picking to logistics is the uncertainty if this would indeed result in a reduction of time. This uncertainty depends on the fact that this project did not consider the feasibility of logistics to take care of the order picking. Phasing out the order picking could therefore work as counterproductive for the overall time consumption. In order to investi- gate this case further a pre-study should be conducted since this project unfortunately did not cover the full analysis of this case. The second case which suggested to replace the current carriers of MK in order to implement a conveyor which would transport the engines. This would conclude in a similar time saving result as the previous case which is a benefit since it would decrease the current costs of the site. However since the total savings has not been fully investigated, there is a need for further investigation more parameters to create a business model for implementing this case. It can also be argued that based on a rough investment analysis of implementing a conveyor system can be unrealistic for MK. How- ever it could be argued back that a conveyor system has been implemented in other segments within the engine assembly. Therefore, a use of core competence within the company can be utilized. Similarly as the previous case this project did not cover enough data to support this solution. The third and last case for the VSM future state analysis consisted of replacing the paper engine cards with a digital engine card. This case showed a clear benefit in terms of cost savings with a saving of 1 488 613 kr per year. This saving was however only based on the saving on the time that was taken for the printing of the engine cards. By implementing displays at all five stations in MK the printing time would be eliminated. Despite the fact that the printing time would be eliminated, other events such as the movement to the place where the computer is situated would probably increase the saving. Also the time it takes to pick up and read the engine card along with the browsing of the pages would decrease the costs further. The practice of using digital engine cards is already implemented in other parts of the engine assembly. This means that core competence can be utilized and that the process is known for the company. Based on the concrete saving of the printing time along with the potential savings, the digital engine cards would be an interesting idea to initiate a project on. It can also be argued that the technology would open new possibilities when improving the workplace. One possibility would be a real-time communication with quality, and product engineers. When it comes to the Failure mode and Effects analysis, several aspects can be discussed. Aspects such as the selection of the parameters occurrence, severity and detection. These parameters were based on daily reports and completed with the input of experienced personnel. There was a risk that the weighing of the parameters could be subjective which can lead to misleading data. This was due to the fact that the analy-

39 sis consisted mostly of qualitative data through interviews. Another risk of misleading data is the risk of repeating data reported in the daily reports. It can be argued that the input from the experienced workers however decreases the risk of misleading data since the data gets validated.

5.1.3 Suggestions of Solutions

These suggestions of solutions could be implemented both for straight and V8 engines. First and foremost, in order for these solution to have a greater impact, a pre- condition in the form of a more balance order inflow is needed. There are many advantages and disadvantages for the new suggestion of layout, but the advantages outweighs the disadvantages. One of the largest advantage is the ability to modify the production system in MK depending on the demand. For example, if the demand is very high on a specific variant, the planning section could plan many Marine Engines and MK will be able to use the new layout as a mixed-model assembly line by dividing the assembly tasks in three stations. On the other hand, this layout is flexible and can be adapted to be used as today, that each station can assemble the whole engine, therefore this solution is very flexible, which is a requirement for MK. At the same time, this solution combines other solutions such as digital engine card, pick-to-light, kitting parts, Just In Time, optimization of assembly sequence and some pre-assembly at the kitting station. The combination is the best solution for the application of MK because of the circumstances at MK. Another advantage if using this layout as a mixed-model assembly is that the assembly of an engine depend on more than one worker, and therefore the quality is increased because of "buddy check", that the worker in the next station controls that the worker before have done correct assembly. There are some disadvantages, such as costs for moving the shelf of parts, investment of a track with rollers and investment of pick-to-light. However, this solution will increase the effectiveness of assembling Marine Engines, but it will only give value if the volume is increased, or at least kept in a relatively high and stable level. The results of the new routines for the engine cards were divided into two segments. One for suggesting an initiation of a new project regarding the implementation of digital screens at each station. The other segment was the suggestion of initiating another project regarding the update of the current engine cards. The implementation of digital screens was discussed in the previous section within case 3. The difference however in the suggestion of the digital screen consisted of a more conceptual creation of a digital system. The reason for this is due to the opportunities that a digital screen provides. One opportunity that a digital screen provides is the possibility to have a real-time feedback system while this is unimaginable in paper form. The pros and cons for implementing digital screens for each station can vary depending on what capability it is expected from these digital screens. One case would be having digital engine cards that could include work instructions for each task from the engine cards. Pros with this case would include aspects such as the ease of training new workers. It would also include a higher level of quality assurance. The cons however would include aspects such as higher costs depending of the system complexity. Also, it would require more work for the product engineer for the preparations for this system. Another case with a lower complexity of the system would for example dis-

40 play a copy of the physical engine card in a digital form. The pros with a system like this in relation to the previous case would mean that there would be no change in the product engineer’s work of today. Also, concrete cost savings such as the elimination of printing along with potential cost savings in forms of other time saving activities regarding paper handling. The cons however could be the opportunity costs in relation to the previous case along with the cost of installing the digital devices. The other solution regarding the continuous update of the engine cards comes with some advantages and disadvantages. The advantages of conducting this project are the important aspects such as quality assurance and possible decrease the assembly time. This suggestion contained both update regarding the speciﬁcations of the engine cards as well as the assembly sequences. It is emphasized in the results that the project that should be initiated needs to involve the experienced workers since they are highly valued within MK due to their competency. The disadvantages are the needs of personnel to adapt to new work routines. However, it is considered that the potential achieve- ments that can be attained will surpass the disadvantages.

5.2 Conclusion

Throughout this project a current state analysis has been successfully executed. The current state analysis exposed information that can bring a clearer view of MK today. The main conclusions regarding the current state analysis are:

• MK is distinguished from the rest of the engine assembly when it comes to the definition of assembly variants and therefore the variants needs to be classified according to section 4.1.1 . The classification ended up in 20 different variants, which is a large number of variants. • MK’s engines can be categorized after assembly time where the main groups are Straight 5/6 cylinder engines and V8 engines • The current state of the VSM concluded in a mean value distribution of 60 percent non-value adding activities and 40 percent value adding activities. This is observed as a problem that can be improved.

The future state analysis that was conducted resulted in:

• Three cases regarding possible events with calculated time savings for each (see section 4.2.1) • An FMEA matrix with suggested measures that correlates with the theme of this project and its suggestions of solutions.

The suggestions for this project are prioritizes after the following:

1. Initiate a project where a pre-study for implementing digital screens in MK. • The proposed goals for the project are suggested to analyze the potential savings in forms of saved times and increased level of quality assurance.

41 2. Initiate a project of optimization of the assembly sequence.

• The aim of this project is to create the best practice when it comes to the assembly sequences. It is emphasized that this project needs to include the experienced workers of MK.

A more detailed view of these project descriptions can be found in Appendix G.

5.3 Reﬂections

It has been a privilege working at Scania engine assembly in the Master thesis project. The thesis workers of this project have learned a lot during this period about the production of marine engines at Scania and about SPS. There have been some successes and difﬁculties during the project. The success is the work itself, the implementation, results and analysis at Scania have been appreciated at the company, which is very important. However, there have also been some difﬁculties such as not being able to attend in the production area due to COVID-19 circumstances. This has lead to some delays in the project regarding collecting data and it have also been a part of limitation in the amount of data collection for this study. Another issue is that the biggest focus in this project has been the mapping of the current state, it took more time than planned and the project dug deeper into the current state than expected. This has lead to less time spent on suggestion of solution. How- ever, the advantage of this is that the current state analysis at MK has been very detailed, which contributes for easier decisions for future improvement.

5.4 Future work

There are some future work from this project that could continue at the production area MK. There are in particular three different future projects that has lead to three assignment directive (AD), which can be found in Appendix G. The ﬁrst AD describes the suggestion "New Layout at MK", which is a results from this project, and needs further investigation before implementation. The second AD is another result from this project, describing the continuous work on the suggestion "Digital screens at each station". The third AD describes the results about "Continu- ous update of engine cards", which also needs further investigation before implementation.

42 References

[1] Scania CV AB, “Facts and ﬁgures,” Available at https://www.scania.com/group/ en/home/about-scania/scania-in-brief/facts-and-ﬁgures.html (2021/02/01).

[2] Scania CV AB, “About Scania,” Available at https://www.scania.com/group/en/ home/about-scania.html (2021/02/01).

[3] Scania CV AB, “Scania i korthet,” Available at https://www.scania.com/se/sv/ home/experience-scania/about-us.html (2021/02/01).

[4] Scania CV AB, “Scania Södertälje - Om oss,” Available at https://www.scania. com/scaniasodertalje/sv/home/om-scania-sodertalje.html (2021/02/01).

[5] M. Oudhuis and S. Tengblad, “The viability of the scandinavian work-life model and the impact of lean production: The case of scania,” Economic and Industrial Democracy, pp. 1–25, 2020.

[6] E. Bryman, A. Bell, Business Research Methods. Oxford: Oxford University Press, 2011.

[7] H. van Driel and W. Dolfsma, “Path dependence, initial conditions, and routines in organizations The Toyota production system re-examined,” Journal of Organi- zational Change Management, vol. 22, no. 1, pp. 49–72, 2009.

[8] T. W. Kehra and M. D. Proctor, “People Pillars: Re-structuring the Toyota Pro- duction System (TPS) House Based on Inadequacies Revealed During the Auto- motive Recall Crisis,” Quality and Reliability Engineering International, vol. 33, pp. 921–930, 2017.

[9] J. K. Liker, The Toyota Way 14 Management Principles, 2nd ed. McGraw-Hill, 2020.

[10] S. Gao and S. P. Low, Lean Construction Management The Toyota Way. Singa- pore: Springer, 2014.

[11] P. J. Gisi, Sustaining a Culture of Process Control and Continuous Improvement The Roadmap for Efﬁciency and Operational Excellence. New York NY: Taylor Francis Group, 2018.

[12] Scania CV AB, “The scania way,” Available at https://www.scania.com/group/ en/home/about-scania/scania-in-brief/how-we-create-value/the-scania-way.html (2021/05/09).

[13] A. Williams, “Plan-do-check-act integrating quality into safety management,” American Society of Safety Engineers, pp. 18–19, 2020.

[14] J. L. García-Alcaraz, M. Oropesa-Vento, and A. A. Maldonado-Macías, Kaizen Planning, Implementing and Controlling. Cham, Switzerland: Springer, 2017.

[15] J. Geraldi and T. Lechter, “Gantt charts revisited a critical analysis of its roots and implications to the management of projects today,” International Journal of Managing Projects in Business, vol. 5, no. 4, pp. 578–594, 2012.

43 [16] X. Wu, M. Haynes, Y. Zhang, Z. Jiang, Z. Shen, A. Guo, T. Starner, and S. Gilliland, “Comparing order picking assisted by head-up display versus pick- by-light with explicit pick conﬁrmation,” Association for Computing Machinery, pp. 133–136, 2015.

[17] J. de Vries, R. de Koster, and D. Stam, “Exploring the role of picker personal- ity in predicting picking performance with pick by voice, pick to light and rf- terminal picking,” International Journal of Production Research, vol. 54, no. 8, pp. 2260–2274, 2016.

[18] S. Aukstakalnis, Practical Augmented Reality: A Guide to the Technologies, Ap- plications, and Human Factors for AR and VR. Crawfordsville, Indiana: Mark L. Taub, 2016.

[19] N. Boysen, M. Fliedner, and A. Scholl, “Assembly line balancing: Which model to use when?” International Journal of Production Economics, vol. 111, no. 2, pp. 509–528, 2008.

[20] N. T. Thomopoulos, Assembly Line Planning and Control. Cham, Switzerland: Springer, 2014.

[21] N. Boysen, M. Fliedner, and A. Scholl, “Sequencing mixed-model assembly lines: Survey, classiﬁcation and model critique,” European Journal of Opera- tional Research, vol. 192, no. 2, pp. 349–373, 2009.

[22] T. A. Abdullah, A. Hashim, B. A. Bakar, and D. A. Wahab, “Use of failure mode and effects analysis (fmea) method in remanufacturing analysis for engine block,” Applied Mechanics and Materials, vol. 465-466, pp. 1026–1033, 2014.

[23] A. Gurumurthy and R. Kodali, “Design of lean manufacturing systems using value stream mapping with simulation: A case study,” Journal of Manufacturing Technology Management, vol. 22, no. 4, pp. 444–473, 2011.

[24] J. Dinis-Carvalho, L. Guimaraes, R. M. Sousa, and C. P. Leao, “Waste identiﬁ- cation diagram and value stream mapping a comparative analysis,” International Journal of Lean Six Sigma, vol. 10, no. 3, pp. 767–783, 2019.

[25] R. M. Tabanli and T. Ertay, “Value stream mapping and beneﬁt–cost analysis application for value visibility of a pilot project on rﬁd investment integrated to a manual production control system— a case study,” International Journal of Advanced Manufacturing Technology, vol. 66, pp. 987–1002, 2012.

[26] A. Chiarini, Lean Organization: from the Tools of the Toyota Production System to Lean Ofﬁce. Milan, Italy: Springer, 2013.

44 Appendices

Appendix A: Gantt chart

45 Appendix B: Risk Assessment

46 Appendix C: Spagetti diagram

47 48 49 Appendix D: Forms for reporting events

50 51 52 53 Appendix E: Layout proposals

54 55 56 Appendix F: VSM and NVA Distributions of timed engines

57 58 59 Appendix G: Assignment Directive (AD) for future work

60 61 62 TRITA -ITM-EX 2021:403