Rapid tooling manufacturability evaluation using fuzzy-AHP methodology

Rapid tooling (RT) processes driven by rapid prototyping (such as stereolithography and selective laser sintering) can reduce mold development lead-time by 50% or more, though there are certain limitations in terms of mold materials, accuracy, and surface finish. This paper presents a systematic approach for manufacturability analysis of molds produced by rapid tooling methods, based on three aspects: mold feature manufacturability, secondary elements compatibility, and cost effectiveness. The geometric features of functional elements of the mold (core, cavity, side core, etc.) are evaluated for manufacturability using fuzzy-analytic hierarchy process (Fuzzy-AHP) methodology. The secondary elements of mold (parting surface, ejectors, cooling lines, etc.) are checked for compatibility with RT mold properties (machinability, wear resistance, and surface evenness). Finally, the cost of RT mold is estimated using a semi-empirical model based on cost drivers and cost modifiers, and compared with that of a conventional mold. The methodology has been demonstrated with an experimental mold. It is useful not only for RT mold process selection, but also for identifying minor modifications to a mold design to improve its manufacturability and economy.

[1]  Bernard C. Jiang,et al.  Development of a fuzzy decision model for manufacturability evaluation , 2003, J. Intell. Manuf..

[2]  Satyandra K. Gupta,et al.  A systematic approach for analyzing the manufacturability of machined parts , 1993 .

[3]  Richard J.M. Hague,et al.  Part shrinkage anomilies from stereolithography injection mould tooling , 2003 .

[4]  Jami J. Shah,et al.  Manufacturability Evaluation Shell: A Re-Configurable Environment for Technical and Economic Manufacturability Evaluation , 2003 .

[5]  Jack G. Zhou,et al.  PARAMETRIC PROCESS OPTIMIZATION TO IMPROVE THE ACCURACY OF RAPID PROTOTYPED STEREOLITHOGRAPHY PARTS , 2000 .

[6]  Edward B. Magrab,et al.  Geometric reasoning for manufacturability evaluation--application to powder metallurgy , 1996, Comput. Aided Des..

[7]  Dana S. Nau,et al.  Systematic approach to analysing the manufacturability of machined parts , 1995, Comput. Aided Des..

[8]  Satyandra K. Gupta,et al.  Manufacturability Analysis of Flatness Tolerances in Solid Freeform Fabrication , 2001 .

[9]  Richard J.M. Hague,et al.  The structure of parts produced by stereolithography injection mould tools and the effect on part shrinkage , 2004 .

[10]  P.K. Gupta,et al.  A Systematic Approach for Analyzing the Manufacturability ofMachined , 1994 .

[11]  Yuh-Min Chen,et al.  Extraction of geometric characteristics for manufacturability assessment , 2003 .

[12]  D. Chang.  Applications of the extent analysis method on fuzzy AHP , 1996 .

[13]  Jami J. Shah,et al.  Domain independent shell for DfM and its application to sheet metal forming and injection molding , 2005, Comput. Aided Des..

[14]  Evangelos Triantaphyllou,et al.  Development and evaluation of five fuzzy multiattribute decision-making methods , 1996, Int. J. Approx. Reason..

[15]  Gang Zhao,et al.  Fast variational design of multiresolution curves and surfaces with B-spline wavelets , 2005, Comput. Aided Des..

[16]  Chua Chee Kai,et al.  Rapid prototyping issues in the 21st century , 1999 .

[17]  David Alan Bourne,et al.  Design and Manufacturing of Sheet Metal Parts: Using Features to Aid Process Planning and Resolve Manufacturability Problems , 1997 .

[18]  Yu Jing,et al.  A discussion on Extent Analysis Method and applications of fuzzy AHP , 1999, Eur. J. Oper. Res..

[19]  KEINVORNAME;;; Nagahanumaiah,et al.  An integrated framework for die and mold cost estimation using design features and tooling parameters , 2005 .

[20]  Han Tong Loh,et al.  Toward generic models for comparative evaluation and process selection in rapid prototyping and manufacturing , 2001 .

[21]  Uwe Kaschka,et al.  Selection and evaluation of rapid tooling process chains with Protool , 2000 .

[22]  Chun Liu,et al.  Conceptual design, manufacturability evaluation and preliminary process planning using function-form relationships in stamped metal parts , 1997 .

[23]  Andrew Y. C. Nee,et al.  A fuzzy set AHP-based DFM tool for rotational parts , 2003 .