The Application Of PFMEA Technology Changes The Valve Housing Line

This item is which aim at an actual production work to match the TRW FAWER COMMERCIAL VEHICLE STEERING (CHANGCHUN) CO.LTD. The corpus of that company be turned by the United States TRW CO.LTD with the FAWER COMMERCIAL VEHICLE STEERING CO.LTD ( the motive vehicle steering works) , the year design the outline to 25 ten thousand set. The company usher in the United States TRW the product of forerunner company the technique to manage the way with business enterprise on the FAW company's commercial vehicle steering item the foundation with motives, and promote market that the business enterprise's product technique level with make the technique level, increase the business enterprise to manage the level, strengthen the business enterprise to competitive ability, and satisfy the FAW change the new truck and other high carry the company to use the need in commercial vehicle market.Because of competition in commercial vehicle market vigorous now, request continuously improve to product, develop engineering , exaltation product quality, decline the low cost depletion. Therefore pass to improve the craft of parts to increase the quality of the parts, its important means that improve the vehicle steering.The thesis will be main with the motive vehicle steering the production line to reform to main research object. Pass to produce the line of reform the exaltation quantity of the valve housing, also the improvement the motive vehicle steering function, and solve the motive vehicle steering rotate, block, heavy, inside and side leak go beyond etc. the quality problem, and lower the cost to claim with customer to measure, and obtained the good economic performance. This article explain to used the CNC lathe equipments and the CNC center equipments to reform the old production line by the new craft of new technique, used PFMEA, used the new technique, and used the" U" type line arrangeand one person operation of many machines, implement One Piece Flow, increased the product quality, and lower to waster, and economize the equipments quantity and the area, and reduce to operator, and realize TPS( the Toyota produce the system) management of target.Now the reason that most enterprises can't guarantee the product quality can reduce for below it:1 product design and process lack the analysis technique of the science norm;2 lack the system and operate of management system;3 lack the reasonable use the advanced equipments and craft equipments of ability;4 lack the verification of the system and science and the way of control process.In 1980's, car enterprises of advanced west used slather robot, CNC machine and CNC line, biggest degree eradicate the limitation that operator's factor result the product quality, and pay attention to operator's factor. Thanks to the advanced technique and manages way perfect combination, and just make to Benz, Toyota etc. company become the outstanding car industry.First Development and problem of the valve housing line Valve housing is important parts, its limitation of quality will directly result in the vehicle steering leak the oil, and make assembly inside leak go beyond, leak, card, heavy, the single side does not return positive, give assemble to bring the difficulty.For solution the quality problem of the valve housing line, at past mostly aim at an each quality phenomenon is one by one a register change, and only resolves the surface problem, and can't resolve problem by the root substance. Along with the machine industry of continuously develop, the variety that auto manufacture industry also experience bigness. Abroad the advanced auto corporation, production line to have already attained to process the CNC line with the technique of initiative measure, used PFMEA (Process Potential Failure Mode and Effects Analysis) and TPS( the Toyota produce the system) management method, can availably resolve the quality problem of the parts and whole automobile and take in to guarantee.Now because economic of the margin, we can't realizes the production method of this kind of high level, but pass to fetch in the FMEA and the TPS, and craft of reasonable and control with process, and can nicely resolve the quality problem of the valve housing.Two, the PFMEA technique application and the target with TPS1, FMEA is Potential Failure Mode and Effects Analysis, is the systematical process. Discovering and evaluation product and process potential failure mode and effects, finding and can avoid or reduce these problem that take place. Pass the above process of written form summary to insure the customer satisfaction, and make the design and the production line is more perfect.The before the event spends time to nicely comprehensive FMEA analysis, can convenience, low costly towards product or process proceed modification, from but alleviate after the event modify.FMEA is classed 4 types into DFMEA( design FMEA) and FMEA( process FMEA),usage FMEA and service FMEA. Among them DFMEA and PFMEA most for in common use.Using PFMEA technique to pass the failure product effects analysis, find out the parts failure mode and its failure reason, and study that failure mode to what system can produce influence.PFMEA should before making tooling fixtures, be initiated before or at feasibility stage, and want to consider all manufacturing process. But Risk Priority Number ( RPN) is a importance evaluation target of PFMEA, and is Occurrence ( O), Severity( S),Detection ( D)'s product, namely RPN=( S)×( O)×( D).When RPN is higher, should be lower RPN.What demand notice is, although PFMEA not depend the changes product the design to overcome the process blemish, but it should be want product that the assemble of product of relevant process design characteristic parameter, for the biggest limit guarantee the satisfy the customer request and expect.2, TPS management a main thought is keeping to stabilize quality, enable to produce can reflect the market's variety in time, and the biggest limit decline cost on gradually exaltation of the foundation. Its core is excelsior produce the way.Three, the application of FMEA technology changes the valve housing lineThe old valve housing line had 13 working procedures,12 set equipments,18 operators;( two teams),the line layout is straight line arrange. Produce the rhythm very unbalanced, in the many mill, produce the efficiency to is low; The equipments is many manual or half automatic drill, and the common lathe etc., accuracy is bad, and the quality is unsteady to settle, waster and repair rate is the higher, wasted circumstance is serious.Pass to adopt PFMEA technique changes the valve housing line, certain TPS management target: Make the valve housing waster rate lowest;( finally zero waster); Realize the valve housing stock and line layout amount is the lowest; Preparation time is the most short (zero preparation time); Produce advance period is the most short, flexible is good; Reduce the parts knock and break and higher efficiency; Machine damage rate is low; The valve housing line circumstance and order is good. And pass MSA, CPK application with guarantee the validity and degree, to make use of the control the plan and SPC to control process to take in to guarantee.The valve housing line have 7 working procedures,6(7) set equipments( because of many blending line produce, and some one need 7 set equipments),6 operators ;(three teams, a per teams two operators, every operator operation 3-4 set equipments);The line layout is a " U" type line alignment. Pass used the CNC, and increase the quality, balanced production rhythm, decrease supernumerary personnel, exaltation work efficiency, stop wasted.Because of adoption FMEA technique to Change the valve housing line, make it from input to output is a time successful, did not pass by iterative of Change and again input process. For push TPS management creates beneficial term. Valve housing quality get to increase, CPK from 1.12 attain 1.64, waster rate from 2.8% as low as 0.0932%.Save the cost for company 13.5 ten thousand RMB/ year, lift the high profit 0.23%.Make use of the above method in the actual work, already successful change the three parts line, and acquisition good result. Pass used PFMEA technique and TPS manage way, and work deep along with the management, each parts line should be changed, the company will have a leap, and thoroughly get away from the drop behind production situation, to also development of the company can produce the positive and profound influence.