Topic 4.5 Production Systems

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Topic 4.5 Production Systems Topic 4.5 Production systems Guiding Questions & Tasks 1. Outline the effect mass production and mechanisation has had on the craft industry. 2. List the advantages and disadvantages of craft production 3. List some examples of products manufacture by craft production 4. Explain why craft production is still commonplace in developing countries 5. Define mechanisation 6. Compare mechanisation to automation 7. Outline how in an automated system the roles of people change 8. List the advantages and disadvantages of assembly lines 9. Outline the role of standardized parts in assembly line manufacture 10. Describe mass production 11. List the advantages and disadvantages of automation 12. List the advantages and disadvantages of mass production 13. List examples of design contexts where mass production would be appropriate 14. Outline how ‘design for materials’ can lead to better designed products 15. Outline why ‘design for process’ is an important consideration 16. Outline why ‘design for assembly’ is an important consideration 17. Outline why Design for disassembly can improve the recyclability of a product and the recovery of materials used 18. List the main considerations when designing for manufacturing Topic 4.5: Production systems The design of a production system requires a complete understanding of a product, its function and the quality of finish. Each system can be unique and specific to the product it is creating, often requiring the designers to adapt their design to be manufactured using certain methods. Essential idea: The development of increasingly sophisticated production systems is transforming the way products are made. Nature of design: As a business grows in size and produces more units of output, then it will aim to experience falling average costs of production—economies of scale. The business is becoming more efficient in its use of inputs to produce a given level of output. Designers should incorporate internal and external economies of scale when considering different production methods and systems for manufacture. Concepts and principles: • Craft production • Mechanized production • Automated production • Assembly line production • Mass production • Mass customization • Computer numerical control (CNC) • Production system selection criteria • Design for manufacture (DfM): design for materials, design for process, design for assembly, design for disassembly • Adapting designs for DfM Guidance: • Advantages and disadvantages of different production systems • Impact of different production systems on the workforce and environment • Production system selection criteria include time, labour, skills and training, health and safety, cost, type of product, maintenance, impact on the environment and quality management • Design contexts where different production systems are used Production systems You are expected to have a deep enough understanding of production systems to be able to make sound decisions when determining which ones are appropriate for a specific job. This includes being able to explain advantages and disadvantages of different production systems, the impact they have on the workforce and environment, and the selection criteria. How do firms choose their method of production? Firms choose their method of production based on a number of different factors, such as: ● The amounts they are likely to sell. ● The product they are making. ● The costs of production. ● The variety of goods expected by customers. [https://en.wikibooks.org/wiki/GCSE_Business_Studies/Methods_of_Production] ​ ​ Craft production Craft production is a small­scale production process centred on manual skills. Advantages and disadvantages of craft production. Consider economies of scale, value of the product, labour, market forces and flexibility of manufacture. Advantages A lot more care is put into making the product as good/nice as possible, therefore the quality tends to be seen as considerably higher than something that was mass­produced. The product can also be customised to fit personal needs, and there is a good deal of flexibility for the designer, customer and craftsman. Much skill is often required for the craftsman; therefore they are able to charge more for the manufacturing of the product. Disadvantages Although the manufacturing process does not require machines for the producer, it takes a great amount of time and effort; therefore it becomes much more expensive for the buyer. Also, with craft production it is not possible to produce on a larger scale. This could mean a loss of profit for the manufacturer, however the higher prices of craft produced products can sometimes make up for this. Another disadvantage may be that the product is not designed for disassembly, so if something goes wrong during the making of it, there are no interchangeable parts. Every piece also becomes more valuable so any defects will be more important. Design Contexts include: one­off products such as custom made furniture, pottery, art and crafts Mechanized production Mechanized production is a volume production process involving machines controlled by humans. Originally, very small numbers of products were made by craftsmen in home workshops. But, the increasing demand for consumer goods following the industrial revolution, meant that larger numbers of products needed to be manufactured in a more efficient way. [http://www.ruthtrumpold.id.au/destech/?page_id=334] ​ ​ The image below shows the Mechanization of Rice Production. When thinking about the advantages of mechanisation think about the efficiency, accuracy, cost, but also the reduction in the need for manual labour ­ which means less jobs for people. Advantages ● The creation of economies of scale … the product is cheaper than craft production ● The quality of the product is improved as fewer human errors will occur, the finish of the product will also be improved. ● Increased wages due to training and becoming skilled. ● Efficiency of production: less time is taken to produce goods Disadvantages ● Redundancy – machinery for labour substitution ● Health and safety. Work conditions are usually poor in the factories, lack of safety standards can be an issue in some cases. Repetitive strain injury. ● Cost of energy, training and capital machinery. Increased wages due to highly skilled operators needed. ● Environmental pollution. ● Boredom for the workers ● Low job satisfaction for workers [http://www.ruthtrumpold.id.au/destech/?page_id=334] ​ ​ Automated production Automated production is a volume production process involving machines controlled by computers. An automated production line is comprised of a series of workstations linked by a transfer system and an electrical control system. Each station performs a specific operation and the product is processed step by step as it moves along the line in a pre­defined production sequence. A fully automated production line does not need people directly involved in the operation, and all or part of the process of the production is completed by mechanical equipment and automated systems. Therefore, in an automated environment, the tasks of human are more likely to change to system design, adjustment, supervision and monitoring the operation of the system rather than controlling it directly. [http://www.rnaautomation.com/blog/benefits­automated­production­lines/] ​ ​ Watch this video for an overview https://www.youtube.com/watch?v=sjAZGUcjrP8 ​ Advantages and disadvantages The main advantages of automation are: ● Increased productivity. ● Improved quality or increased predictability of quality. ● Increased consistency of output. ● Reduced direct human labor costs and expenses. ● high degree of accuracy ● Replacing human operators in tasks that involve hard physical or monotonous work ● Replacing humans in tasks done in dangerous environments (i.e. fire, space, volcanoes, nuclear facilities, underwater, etc.) ● Performing tasks that are beyond human capabilities of size, weight, speed, endurance, etc. ● Economic improvement: when a state or country increases its income due to automation like Germany or Japan in the 20th Century. ● Frees up workers to take on other roles. ● Provides higher level jobs in the development, deployment, maintenance and running of the automated processes. The main disadvantages of automation are: ● Security Threats/Vulnerability: An automated system may have a limited level of intelligence, and is therefore more susceptible to committing errors outside of its immediate scope of knowledge (e.g., it is typically unable to apply the rules of simple logic to general propositions). ● Unpredictable/excessive development costs: The research and development cost of automating a process may exceed the cost saved by the automation itself. ● High initial cost: The automation of a new product or plant typically requires a very large initial investment in comparison with the unit cost of the product, although the cost of automation may be spread among many products and over time. [https://en.wikipedia.org/wiki/Automation#Advantages_and_disadvantages] ​ ​ Assembly line production Assembly line production is a volume production process where products and components are moved continuously along a conveyor. As the product goes from one workstation to another, components are added until the final product is assembled. Advantages For manufacturers, the benefits of assembly line production are enormous. An inherent part of the idea of assembly lines is that each item produced is as close to identical as possible. This allows
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