Research Of Die Cost Evaluation System Of Auto Panels Based On Group Technology

Die of automotive body panels is one of the important technical equipments in automotive body producting.Throughout the whole process from R&D to marketing of a new automotive model,the design,manufacture,commissioning cycle of automotive body stamping die is longer,and the investment is the largest.With the requirements of shorting Auto-body type changint cycle and increasing demand,die cost evaluation of automotive body is paid more and more attention in the product design process.Die quotation work integrates technology,experience and market together,and is one of the key work related to whether or not the die corporation can receive orders successfully, evolve producting favoringly and win some profits for the enterprise.For an automotive company,die cost evaluation of automotive body will be a major fator of producting cost evaluating for a new model in the stage of auto-body type selection when researching and developing a new production.Rapid and efficient die cost estimation is has a practical economic significance for cost evaluation and decision-making.Automotive panel die is mostly piece production,the cost estimate has complexity,empirical, ambiguity and a certain degree of repeatability.This paper considered the strong similarity among automobile panels of the same type,among stamping dies of the same type,and among cost estimates of work itself sufficiency,then launched a study on the issues related to die cost evaluation of automotive body panels based on Group Technology.This paper maily researched in the following four aspects:First,this paper discusses in detail the major factor impacting stamping die cost evaluation of automotive panels and the imapcting way of these factors.Stamping die cost evaluation formula suitable for automotive panels is proposed after suffficiency investigating the practical producting process and quotation process of automotive panel stamping die. Compared to the general midle or large scale stamping die cost estimate formula,this formula considered the similarity of automotive panels and the stamping die sufficiently,did not need to deploy a large number of parameters,and could be more terse and conviniet applicated.Besides that,the establishment of relevant parameters in the formula is closely combined with the accumulated datas in years production of die company,so that the patameters are more reliable,and evaluated die cost could be more closely with the practical die producting cost.Secondly,in order to manage a large number of information involving in die cost evaluation work of automotive panels such as automotive panel type,die type,stamping processes,and cost estimated parameter effectively,a coding system for die cost evaluation system of automotive panels was established based on GT coding technology,achieving information management effectively,convenient for inquiring relevent information quickly in the process of automotive panel die cost estimating,ensuring the result of die cost evaluation of automotive panel effective and stable.Third,the issue of stamping process steps fast formulation was studied based on the concept of typical components in the field of Group Technology.Stamping process steps fast formulation maily consists of two parts of work.The first part was the establishment of comparing stamping process steps library,including the following steps:Classified automotive panels according to the forming difficulties,constituted different product types.Then grouped products in the same type in accordance with the geometric topological shapes,constituted different product groups. (?) Established compared parts models respectively for each product groups,analysed the geometric structures and process characteristics of these compared parts,and design compared stamping processes correspondingly.(?) Abstracted compared stamping processes into compared stamping process steps.The aggregation of these compared stamping process steps constituted compared stamping process steps library.The second part of the work was the instantiation of the stamping process steps,including the following two steps:(?) In the initial design stage of stamping process,the die cost evaluation system of auto panels called the compared stamping process steps library in the system automaticly and selected the correspongding compared stamping process steps,according to the product characteristics codes.(?) The users consulted the compared stamping process steps provided by the system, combining with the practical structure and process characteristics of the current panels, confirm these processs steps as the design-finished stamping process steps;or made a minor adjustments on the compared stamping process steps,to form the final.Through these two steps,the establishment of stamping process steps of auto panels could achieved rapidly.Fourth,the frame of die cost evaluation system of auto panels was constructed aiming at the general flow and work characteristics of the die cost evaluation,based on these three studies above.Oriented by this frame,on the public interface of Jilin University self-developing automotive panel stamping CAE software KMAS,the die cost evaluattion system of auto panels KMAS-DQS was developed in Visual C + + 6.0 and 7.0 compiling environment based on COM componentized developing technology.The system consisted of five modules, namely:(?) Panels characteristics information collectiong module; (?) Stamping process steps fast establishment module;(?) Cost estimate information requirement module;(?) Report form of die cost eveluation of auto panel export module; Die cost evaluation system of auto panel KMAS-DQS was able to respond to the customers' needs quickly,realized computer aided die cost rapidly evaluation of auto panel. In this paper,Group Technology was firstly applied to the field of die cost evaluation of auto panels.By utilizing the geometric shape similarity of among automotive panels in the same type,the experiential dependence and repeatability of die cost evaluation,complex issues were made simple and standard applicating Group Technology,and die cost rapid evaluation system of automotive panels was achieved.The developed die cost evaluation system of auto panels had the advantages of rapid,stable and reliable.