2022年車輛工程汽車專業(yè)外文翻譯

1、Downloaded from SAE International by Guangxi University of Tech, Sunday, March 01, The New Approach to Automotive Vehicle Assembly Process-26-0061 Published 01/14/Sanjay NibandheMahindra Mahindra, Ltd.CITATION: Nibandhe, S., The New Approach to Automotive Vehicle Assembly Process, SAE Technical Pape

2、r -26-0061, , doi:10.4271/-26-0061.Copyright SAE International and Copyright SAEINDIAAbstractThe paper presents integrated approach to Automobile Assembly Process. The approach describes about “Production Process Simulations” for New Products under development. This leads towards design verification

3、 during early prototype assembly process establishment for newly developed automobile vehicles and its control plan which regulates to final production practice.In recent years the Indian automotive business is expanding and with growing needs of faster new product development, the cycle time reduct

4、ion becomes very crucial for environmental and economic reasons. The Lean production assembly and robust engineering processes are optimized in this approach.Its an advanced mechanism to identify process failures during final production setup. The experimentation has resulted towards establishing mi

5、cro level study and critical stages to be captured well in advance for better planning. The actual verification of design at early stage builds confidence in New Product Development.This approach covers of all types of vehicle manufacturing, product mix, and deliverables of vehicle quality. The key

6、achievement is by ensuring of significant & critical design parameters, engineering specifications, quality targets and customer perceived quality. The robust planning and decision making results in easiness of final product assembly line.This paper is an approach to create an integrated vehicle ass

7、embly process for New Product Development (NPD), in comparison with existing production process of vehicle assembly.IntroductionAt present we have 11 manufacturing facilities in India & abroad. As our Product Development center & manufacturing plants at distant locations. It is not so easy to assemb

8、le vehicles at manufacturing plants without any preparation. Similarly manufacturing facilities &Product development center are not closed to each others, therefore itbecomes very difficult to establish new products at early stage. In view of this we proposed & established miniature pilot line on wh

9、ich all the experimentations can be carried out. The present practice needs to modify in a greater way for fast product developments with multiple projects & variants.One product - one production line is a conventional practice over the years. Following process flow chart describes about existing ve

10、hicle manufacturing process used by OEMs.Fig.1. Existing vehicle manufacturing process.To have an innovative approach in Product development center for vehicle assembly one has to simulate future production practices to be deployed.3 There is need to inject the advanced manufacturing quality aspects

11、 in it. The independent Pilot production facility for batch productions of prototype vehicles becomes vital. All experimentations need to try out before take up final process settings.Now a days “Product life cycle” span is reduced drastically and hence the Original Equipment Manufacturer (OEM) need

12、 to introduce new products quite often. The periodic new product introduction becomes necessity to be successful in the business. Now that different models and variants thereof are required in multiple numbers, to prove dynamic need of customers perspective. The base platforms are common for these v

13、ariants and hence, need to accommodate on same production line. i.e. Base model is Swift & new variants Swift Desire, Eartiga etc. are produced on one production line. This has created need for an appropriate product mix, multiple models manufactured on one production setup.3Downloaded from SAE Inte

14、rnational by Guangxi University of Tech, Sunday, March 01, The type of vehicles like monocoque, semi monocoque and body-over chassis are familiar. All three types of construction needs to have different process setting & sequence while assembly. It needs to accommodate on same line separately or in

15、combination with flexibility. For NPD cycle it needs to be tryout on pilot setup and then make arrangement for final production line. Thus pilot line and simulations becomes the foundation for successful implementation for New Product Development.The integrated process is focusing on lean production

16、 practice and cycle time reduction along with design verification, establishing manufacturing quality characteristics & production norms optimization.1 The task performed across the various projects are almost similar and can be benefit from the proposed process. The focus will be towards optimizing

17、 usage of Fixtures, Gauges, Tools, and methods to be deployed for manufacturing with following are the key aspects to be established.Design Readiness: Design for Manufacturability (DFM) and Assembly (DFA).Design for Serviceability (DFS) and ensure easiness for servable items.Digital mockup & Virtual

18、 simulationBOM confirmation and complianceAssembly Simulation: Process Control specificationsSOP: Process Control PlanDesign Verification, Torque Integrity.Front Loading for manufacturing quality aspectsProduct Quality mappingProduction Norms optimization.This paper is a Review of above processes in

19、 order to prepare for faster establishment of NPD process and to incorporate for higher design and process level accuracy form the beginning of product launch preparation. Please refer appendix 1 for the innovative approach adopted.1. Design readiness, DFM & DFA: This process provides confirmation f

20、or planned sequence of operations, then proper clearances at each stages. Its made applicable for all components & aggregates used in vehicle assembly. In a process confirmation various alternatives are evaluated. Right selection with process sequence & tool can be defined at early stage. This facil

21、itates procurement of the right tools and confirm suitability The new method of virtual simulation provides best norms for fast and easy working. i.e. Cross Car beam bolts fitment is blind area for visibility. This needs high skill & best judgment for operating person else you cant verify as it will

22、 be very difficult to verify afterwards. Such critical areas are identified to reduce the dependency of workmen skills to larger extent. 4The design for manufacturability and design for assembly (DFM & DFA) is confirmed effectively. The micro level details are worked out and process for assembly is

23、defined. i.e. Torque control right angle approach tool with extension will be suitable for narrow space for tightening approach.6 This process becomes vital important for deciding the assembly practices. Most of the automotive companies are started using these practices. However the scope is quiet v

24、ast &unlimited. The entire engineering industry wherever assembly process is involved; will be using it in future. I.e. Computer industry, Watch industry, White goods industry etc.2. Design for Service: Similarly design for serviceability (DFS) is another requirement which needs to confirm at early

25、stage. All serviceable parts from different systems & aggregates may require to remove & refit during service. The set of tools used are quite different than production tools. Hence it needs to confirm adequate clearances for approach of standard tool kit.In few cases standard tools may not be usefu

26、l unless & until special tools are designed & tried out i.e. removal of lubrication filter due to low access & space available. In such cases special tools are manufactured & provided for large number of service destinations. The specific methods & recommended practice will be planned with DFS study

27、. The virtual study confirms easiness of operations at every level. Adequate time planning can be done to make such tools available for service needs. This process is very important considering long term effects.3. Digital Mockup & Virtual Simulation: In Recent decade the automobile assembly process

28、 becomes highly progressive & innovative. The accuracy level required for vehicle assembly needs to be very high in terms of fit finish, overall quality & customer satisfaction. The productivity is also equally important with multiple models/variants of vehicles to produce, simultaneously on the sam

29、e production line. The process setting at every stage becomes complex.Vehicle assembly process starts with the sequence of operations to follow on assembly conveyor. Every element of sequence relates with tool approach in predetermined way of working. The specifications which are drawn by design, ne

30、eds to achieve with those tools. The fixtures & methods deployed for easiness of operations plays major role. The space available for component placing & tool accessibility for tightening needs to be considered very carefully.This needs to study in detail with CAD systems at very early stage. Accord

31、ingly the layouts, CAD models & proper packaging becomes prerequisite at design stage. Digital Mock up and Virtual simulation needs to plan with details of tools to be deployed. The way the components are placed in assembly sequence & the methods for tightening will be used in DMU. The virtual study

32、 will used for complete study of layouts, clearance and space management in packaged condition. In todays world virtual simulation is supported by digital mock-up process & software extensively used for study and decision making. The training needs can be identified and planned in advance. Adequate

33、time planning can be done to make such tools available for service needs. I am sure Auto OEM most of them are using it however other engineering industry can also think over for its wide applications.Virtual BOM Verification: The verification of BOM, correct hardware is confirmed at early stage, Vir

34、tual BOM simulation is new methodology developed & helped for first time right BOM release before start of physical assembly.Assembly Simulation: Process Control Specifications: Physical verification of assembly process is necessary to confirm output of physical simulations. During first pilot batch

35、 or prototype stage mostDownloaded from SAE International by Guangxi University of Tech, Sunday, March 01, of the parameters are verified. Inputs are given to design & process team about confidence and non-compliance areas. Accordingly design changes are carried out and reconfirm for easiness.The Pi

36、lot line is a setup to try out assembly of proto vehicle at miniature line, processes and tools tryout. At first stage of design, all process sequences and innovative concepts about new methods & tools gets verified. The norms are not seen as constrain and the flexibility helps in achieving targets.

37、 The optimization of equipment and process confirmation will be carried out well in advance stage. The production norms, gets tryout along with Design for Manufacturing (DFM), Design for Assembly (DFA) and Service Aspect in Manufacturability (SAM) are verified. i.e The new introduction of aggregates

38、 like Auto Transmission is to be adopted in latest vehicles at the proto stage, all functional & fitment tryout, training and practicing can be done at Pilot stage. Afterwards it can be set with refined version at Production line.6. SOP & Process Control plans: Assembly standard operating process (S

39、OP) is defined for consistency in sequence to follow by any operator for ease of operation in given time limit. e.g. door window glass fitment is quite complex for new designs. Hence CAD Virtual simulation are used to establish actual tryout in assembly. This helps to define process. Once actual try

40、 out is carried out successfully, it becomes confirmation for process to follow in predetermined sequence. Finally manufacturing team will be trained on this type ofPilot Line. Accordingly SOP & early training is important for manufacturing setup of production.“Product specific process control plan”

41、 is another important milestone. The engineering team need to take decisions about methods, fixtures, tools & gauges (FTG) to be used during the assembly process. The plan for target production level is key element for design of FTG. Accordingly the process norms are defined & worked out for through

42、put time & TACT time of operations. The efforts required by operator need to be evaluated to minimize the fatigue for long stretched workouts. E.g. In case of multi utility vehicles the middle seats are heavy in comparison with other parts for operations like Pick, lift, place & fix are the activiti

43、es which consumes time. Also multiple operators involved & repetitive job create fatigue after some time. Hence manipulators are designed to pick & place with orientation is quite important. If this set up is flexible then this fixtures need to suitable to multiple designs of seats holding and movem

44、ent. Thus fixture design plays important role in control plan. Another example of flexible powertrain mounting (Engine & Transmission) should be having approach for all six directional movements which brings easiness for aligning, locating & proper positioning.This facilitates need to set to achieve

45、 desired production rate with comfortable practice. The arrangement at every stage of production conveyer line will be planned with flow for material feeding, hardware & tools. This will ensure effectiveness for working positions & easy approach at working stages predominantly. The norms are defined

46、 with respect to best achievable production rate.Torque Integrity: The next important element of process control is specified as “torque requirement”. The every joint is defined with type of hardware & applicable torque. The torque value varies from material & hardware used for fixing position. The

47、elasticity limit forplastic part is different than metal part. It depends on tightening surface and clamping location; also material & type of joint makes difference for torqueing values. Once the component is fixed with specified torque value, it need to be retained in a position for long duration

48、to sustain the vibrations from various road conditions & forces exerted on the joints.The study need to carry out at early stage for integrity of torqueing & its life to retain over the period. This can be defined in terms of years or number of kilometers to cover till end of life situation i.e. har

49、dware used for fixing internal trim parts & hardware used for fixing metal to metal parts at suspension joints will have difference in torque value with respect to vibrations & relative movements. Hence specifications becomes critical at every stage.Thereafter the torque retained capacity vary with

50、respect to specifications due to loosening effect due to usage or Life cycle. The reason behind these changes needs to study for material property, number of clamps & its positions. One also needs to anticipate natural tendency of loosening or over tightening effect. The optimistic torque value for

51、every component needs to be set in advance.Residual torque will be confirmed for each clamping/ tightening locations for withholding value. In case the residual torque value changes, it need to be reviewed for right process at early stage.Similarly, if specified values need to revised, the decisions

52、 can be taken in advance. E.g. Trim plastic components deformed at localized clamping area which tends to reduce torque against specification value. Similarly number of clamping positions also plays major role, for large components like sheet metal panels, plastic or jute material trim pads.7. Desig

53、n Verification: The design verification process gets starts with right fitment of components, aggregates without any trouble where predetermined sequence of operations need to follow with specified tools & processes. This provides confirmation for compliance of process. In case of failures, the desi

54、gns are reevaluated& iterated at early stage. The tolerance stacks & its combined effect on multiple parts fitment needs to be verified.2 In certain cases human skills become important for fitment of components i.e. the door alignment & adjustment of hardware for gaps & flushness with level of door

55、and body. 9. It will also affect door locking & unlocking efforts. Predetermined value of door efforts are one of the key parameters for customer perseverance. Similarly pedal efforts are dependent on multiple components fitment i.e. relates to clutch & brake systems. The components used in assembly

56、, their positions & tolerance, will affect for pedals movements. The resultant is low or high pedal pressure which is another parameter for customer satisfaction. In this way design verification of systems & aggregates are determined for specific requirements.Additionally critical gaps & clearances

57、are another parameter to verify at early design stage.8 This requires to verify clearances in static conditions between nearest two parts to be measured after assembly. The CAD layout indicates designed gaps & the actual gap available on vehicle needs to compare. The variation in either conditions (

58、i.e. low or high) will have consequential effects. In case of lesser clearance, it may hit to other components or transfer forces / load / heat to the other components which will effect functionality. InDownloaded from SAE International by Guangxi University of Tech, Sunday, March 01, other way; the

59、 excessive gap may create effect on opposite side components. The shift condition will be observed and may create effects to the other assembled parts.These situations at static conditions are different than dynamic conditions. The lesser gaps will make assembly critical & create some of the issues

60、related to noise and vibrations, and in worst condition failures. The engine rock at idle RPM & due to rubber mounts characteristics; it will allow engine oscillations. Hence it requires to confirm for adequate clearance during working conditions. There should be safe gap to avoid hit & failure with