The development of equipment to measure and monitor wear inside gun barrels Application of the product development process Utvecklandet av m¨atutrustningf¨or¨overvakande och m¨atningav slitage i eldr¨or Till¨ampandet av produktutvecklingsprocessen Emil Perkovic Faculty of Health, Science and Technology Degree Project for Master of Science in Engineering, Mechanical Engineering 30 hp Supervisor: Abdulbaset Mussa Examiner: Jens Bergstr¨om 2020-06-22 1.0 ABSTRACT The gun barrel is one of the most important parts of the whole artillery system. During firing, the wear leads to reduced performance and availability. Wear in gun barrels has different types of erosion mechanisms, in particular chemical-, thermal- and mechanical erosion. This takes place in the internal ballistic process when the projectile is fired from the gun barrel and it will affect the external ballistic parameters. Therefore, an equipment is needed to monitor and measure the wear inside different calibre gun barrels. Wear in gun barrels takes place under extreme conditions during firing due to high gas pressures and high temperatures arise as propellant burns. The present thesis aims to develop a type of measuring equipment that should be able to measure and monitor wear inside gun barrels between the diameter ranges of A-C mm. In this master thesis, the product development process has been adapted in order to reach the following goal which is to accomplish a technical solution for the problem associated with wear in gun barrels. The product development process is a systematical approach of developing new products. The different steps that have been evaluated are the product specification, generation of concepts, selection of concepts and layout- and detail design. Before these steps where performed, a project plan was done in order to organize the project. This was then followed by a literature review to obtain information about the problems in the project and to find inspiration from similar applications. The results of the product development process led to a concept of a moveable measure-head which uses a crawler to move inside the gun barrel and adapters to be able to use inside different calibre gun barrels. Then a rotating 3D-laser scanner to measure the change in diameter of the bore. A laser distance sensor and a receiver in order to measure the straightness and to be able to know the position of the moving measure-head in the gun barrel. At last, a wireless camera to monitor the wear inside the gun barrel. The selected concept has been developed and potential solutions for the problem have been described and formed. For the next phase of the project, the concept needs to be developed into a complete model. The next phase of the project is the prototype testing phase. Keywords: Gun barrel, wear, laser, measure-head, crawler i ii SAMMANFATTNING Eldr¨oreret¨aren av de viktigaste komponenterna i hela artilleriet. Vid avfyrning av projektiler, kan slitaget leda till s¨anktprestanda och antr¨affbarhet.Slitaget i eldr¨or ¨arav olika former av erosion, i synnerlighet kemisk-, termisk- och mekanisk erosion. Detta fenomen sker framf¨orallti den interballistiska processen n¨arprojektiler skjuts ut fr˚aneldr¨oretoch p˚averkar ytter ballistiska parametrar. S˚aledesbeh¨ovsdet en ny typ av produkt i form av utrustning f¨or¨overvakandet och m¨atningav slitaget f¨oreldr¨orav olika kaliber. Slitaget i eldr¨orsker under extrema f¨orh˚allandenunder avfyrning och leder till h¨ogtgas tryck och h¨ogtemperatur fr˚andrivladdningen. Detta leder till att m˚aletmed examensarbetet ¨aratt utveckla en typ av utrustning f¨or¨overvakning och m¨atningi eld¨orfr˚ankaliberstorlek A-C mm. F¨ordetta master examensarbete har produktutvecklingsprocessen applicerats f¨oratt ta fram en tekniskt lagt l¨osningf¨orproblemet associerat med slitage i eldr¨or.Produktutvecklings- processen ¨arett systematiskt tillv¨agag˚angss¨attf¨oratt ta fram nya produkter. De steg som ing˚ari denna process och som ha blivit utf¨orda¨aren produktspecifikation, konceptgenerering, konceptval samt layout- och detail design. Innan dessa steg utf¨ortsgjordes en projektplan f¨or organisation av projektet. Detta f¨oljdessedan av en litteratur studie f¨oratt l¨asain sig p˚a ¨amnetsamt finna inspiration fr˚anliknande applikationer f¨orprojektet. Resultatet av produktspecifikationen ledde till ett koncept i form av ett ”r¨orandem¨athuvud" d¨aren "crawler" anv¨ands f¨oratt ta sig fram i eldr¨oretoch adapters f¨or att till¨ampasi ¨ovriga kaliber storlekar. Sedan en roterande 3D-laser scanner f¨oratt kunna m¨atadiameterskillnad. En avst˚andslaser sensor och en mottagare f¨oratt m¨atarakhet samt position f¨ordet ”r¨orande m¨athuvudet" i eldr¨oret.Slutligen en tr˚adl¨oskamera f¨or¨overvakning av tillst˚andeti eldr¨oret. F¨oratt dra en slutsats har ett koncept till ett ”r¨orandem¨athuvud" utvecklats samt l¨osningsf¨orslagf¨orproblemen beskrivits samt formulerats. F¨orkommande steg i processen beh¨ovskonceptet utvecklats till en komplett prototyp. N¨astasteg av projektet ¨arprototyp testing fasen. iii ACKNOWLEDGEMENTS First of all, I would like to thank my supervisor Abdulbaset Mussa at Karlstad University for his commitment and guidance during my work, providing me help and support. I also want express my sincere gratitude to my supervisor Fredrik at the company for his support during the project. At last, I want to send a special thanks to Martin, Jonathan, Sten and Eva for providing me with help and advice. Thank you. Emil Perkovic 22nd June, 2020 Karlstad, Sweden iv TABLE OF CONTENTS List of Figures ...............................................................................................................viii List of Tables ................................................................................................................. x Nomenclature & Abbreviations................................................................................. xi 1 Introduction ............................................................................................................. 1 1.1 Problem formulation ........................................................................................... 1 1.1.1 Research limitations ........................... 2 1.2 Aim of this study ................................................................................................ 2 1.3 About the company ............................................................................................ 2 2 Theory & Literature review.................................................................................. 3 2.1 General information about guns ......................................................................... 3 2.1.1 Gun barrel internal geometry ...................... 4 2.1.1.1 Rifling..............................4 2.1.1.2 Smooth barrels.........................4 2.1.2 Propellant................................. 5 2.1.3 Calibre................................... 5 2.1.4 Gun barrel material............................ 5 2.1.5 Projectile ................................. 5 2.1.6 Muzzle................................... 6 2.2 Typical damage mechanisms in gun barrels........................................................ 6 2.2.1 Modes of failure.............................. 8 2.2.2 Chemical erosion............................. 9 2.2.2.1 Carburization.......................... 10 2.2.2.2 Oxidation............................ 11 2.2.2.3 Hydrogen erosion, embrittlement and cracking........ 11 2.2.3 Thermal erosion.............................. 11 2.2.4 Mechanical erosion............................ 12 2.2.5 Effects of wear .............................. 13 2.3 Wear measurements ............................................................................................ 14 2.3.1 Inspection and observation........................ 14 2.3.1.1 BEMISTM ............................ 16 2.3.1.2 RIB 4D............................. 17 2.3.1.3 AGI Barrel Measuring System................. 18 2.4 Methods for surface analyses .............................................................................. 19 2.4.1 Contacting Techniques.......................... 20 2.4.2 Non-Contacting Techniques ....................... 21 v 2.4.3 Scanning Probe Microscopy ....................... 22 2.5 Measuring methods in different application ........................................................ 23 2.5.1 Thin layer activation........................... 23 2.5.2 Stamping industry ............................ 23 2.5.3 Break friction materials ......................... 24 3 Method...................................................................................................................... 25 3.1 Product development process.............................................................................. 25 3.2 Literature study .................................................................................................. 26 3.3 Product specification........................................................................................... 27 3.4 Concept generation ............................................................................................. 28 3.5 Concept selection ................................................................................................ 29 3.6 Layout- and detail design.................................................................................... 30 4 Results....................................................................................................................... 32 4.1 Literature study .................................................................................................