Design for Injection Molding: Balancing Mechanical Requirements, Manufacturing Costs, and Material Selection

1995 ◽  
Author(s):  
Kurt A. Beiter ◽  
James M. Cardinal ◽  
Kos Ishii
Keyword(s):  
Cycle Time ◽  
Material Selection ◽  
Performance Measure ◽  
Production Costs ◽  
Manufacturing Cost ◽  
Manufacturing Costs ◽  
Time Estimates ◽  
Current Implementation ◽  
Molded Parts ◽  
Design Selection

Abstract This paper describes a procedure for considering mechanical requirements, manufacturing costs, and material selection in the design of injection molded parts. The benefit of this approach is the simultaneous consideration of the implications of material selection and part geometry on estimated manufacturing cost during candidate design selection. The current implementation uses the allowable deflection of a flat plate as an example performance measure. Manufacturability concerns include required part thickness and gating scheme to adequately mold the part, and a resulting cycle time based on part cooling time estimates. Part manufacturing cost includes material cost, cycle time, and production costs. A PC-based and CAD-integrated program illustrate our proposed procedure.

scholarly journals System Cost Based Material Selection for Engineering Thermoplastics

1997 ◽  
Author(s):  
Kurt A. Beiter ◽  
Kosuke Ishii
Keyword(s):  
Cycle Time ◽  
Material Selection ◽  
Production Costs ◽  
Manufacturing Cost ◽  
System Cost ◽  
Time Estimates ◽  
Current Implementation ◽  
Material Choice ◽  
Design Selection ◽  
Application Requirements

Abstract This paper describes system cost based material selection, a computerized procedure for considering mechanical requirements, manufacturing costs, and material selection in the design of injection molded engineering thermoplastic parts. The benefit of this approach is the simultaneous consideration of material choice and part geometry on estimated manufacturing cost during candidate design selection. Using cost as a material selection measure permits the examination of system cost as a function of application requirements. The current implementation uses the allowable deflection of a flat plate and equivalent system stiffness as performance measures. Manufacturability concerns include required part thickness and gating scheme to adequately mold the part, production costs for meeting part tolerance requirements, and a resulting cycle time based on part cooling time estimates. Part manufacturing cost includes material cost, cycle time, and production costs. An example of a desktop printer shows the merits of this approach.

Incorporating Dimensional Requirements Into Material Selection and Design of Injection Molded Parts

1996 ◽  
Author(s):  
Kurt A. Beiter ◽  
Kosuke Ishii
Keyword(s):  
Mechanical Performance ◽  
Material Selection ◽  
Production Costs ◽  
Research Approach ◽  
Manufacturing Cost ◽  
Part Geometry ◽  
Molded Parts ◽  
Injection Molded ◽  
Selection For ◽  
Design Selection

Abstract This paper presents a methodology for incorporating part dimensional tolerancing into material selection for engineering thermoplastics. This work builds on the authors’ previous efforts on integration of mechanical performance and manufacturing cost into candidate design selection. The benefit of this approach is the simultaneous consideration of the implications of material selection and part geometry on estimated manufacturing cost during candidate design selection. The research approach uses the Pressure-Volume-Temperature (PVT) method to estimate shrinkage in thermoplastic parts. The authors then present a method for calculating production costs for meeting part tolerance requirements. Example calculations and a computer program illustrate the proposed methodology.

scholarly journals Decomposition-Based Assembly Synthesis of Multiple Structures for Minimum Production Cost

2003 ◽  
Author(s):  
Onur L. Cetin ◽  
Kazuhiro Saitou
Keyword(s):  
Production Cost ◽  
Economies Of Scale ◽  
Structural Strength ◽  
Production Costs ◽  
Manufacturing Cost ◽  
Manufacturing Costs ◽  
Multiobjective Genetic Algorithm ◽  
Trade Offs ◽  
Multiple Structures

An extension of decomposition-based assembly synthesis for structural modularity is presented where the early identification of shareable components within multiple structures is posed as an outcome of the minimization of estimated production costs. The manufacturing costs of components are estimated under given production volumes considering the economies of scale. Multiple structures are simultaneously decomposed and the types of welded joints at component interfaces are selected from a given library, in order to minimize the overall production cost and the reduction of structural strength due to the introduction of joints. A multiobjective genetic algorithm is utilized to allow effective examination of trade-offs between manufacturing cost and structural strength. A new joint-oriented representation of structures combined with a “direct” crossover is introduced to enhance the efficiency of the search. A case study with two aluminum space frame automotive bodies is presented to demonstrate that not all types of component sharing are economically justifiable under a certain production scenario.

Upper-Extremity Prostheses: A Renewed Approach

2009 ◽  
Author(s):  
Alwyn P. Johnson ◽  
Bradley Veatch
Keyword(s):  
Upper Extremity ◽  
Galvanic Corrosion ◽  
The United States ◽  
Manufacturing Cost ◽  
Heavy Duty ◽  
Axial Loads ◽  
Manufacturing Costs ◽  
Ongoing Development ◽  
Universal Interface ◽  
And Function

Upper-extremity (UE) prostheses are increasingly more functional and proportionately more costly, rendering them largely unattainable for impoverished amputees in the United States (US) and abroad. Recognizing the increasing need for appropriate devices, PhysioNetics, LLC is developing a heavy-duty, transradial body-powered (BP) UE prosthesis which can be prescribed with minimal instruction. The design of the key components, the split-hook terminal device [TD] and universal adjustable interface is presented in this paper. The TD is primarily fabricated from plastics to eliminate galvanic corrosion in saltwater environments, weighs 5.4 oz (153 g) and uses inexpensive rubber bands to generate pinch force. Unique gripping contours provide versatile grasp and replicate five (5) prehension patterns while six (6) discrete force settings provide 2 – 17 lbf (8.9 – 76 N) of pinch. Three (3) universal interface sizes (small, medium, and large) accommodate most amputees and comfortably support axial loads up to 40 lbf (178 N). Estimated manufacturing cost for a complete unit is less than US$250. Field testers report lower but comparable comfort to their individually custom-fabricated interfaces, and are highly satisfied with fit and function of the prosthesis overall. Ongoing development includes reduction of manufacturing costs, increasing interface comfort and implementing task-specific variant designs.

scholarly journals Influence of bifurcation on thinning, productivity and harvester production costs of Pinus taeda L.

2020 ◽  
pp. 1259-1263
Author(s):  
Carlos Cézar Cavassin Diniz ◽  
Romano Timofeiczyk Junior ◽  
Renato Gonçalves Robert ◽  
Eduardo da Silva Lopes ◽  
João Carlos Garzel Leodoro da Silva ◽  
...  
Keyword(s):  
Pinus Taeda ◽  
Cycle Time ◽  
Production Costs ◽  
Total Production ◽  
Plantation Forest ◽  
Operating Cycle ◽  
Operational Cycle ◽  
Time And Motion ◽  
Motion Study ◽  
Pinus Taeda L

In this work, we present that how bifurcation in Pinus trees can influence productivity and harvester production costs. Our example draws from one harvesting machine that works in thinning operations in forest plantations of Pinus taeda L. in a small Brazilian forestry company. To get daily productivity, we use the machine’s system, which provides such daily information as total production. We also used a time and motion study to obtain the meantime to cut, delimb, and process the tree stem into logs. In this way, we separated the normal trees from the forked trees to get the operating cycle time of the machine and get the productivity to the two types of trees. The continuous timing method was used for this purpose. The results show an increase of up to 22.9% in the operational cycle time for cutting forked trees, resulting in reduction of productivity of 5.58 m³ for each hour worked. The production cost increased by 23.3% on operation of forked trees, as the machine took more time to perform the partial activities of the operational cycle. This study can help many companies and contractors to calculate the appropriate productivity and production harvest cost according to the type of tree stems from the plantation forest.

Study on Optimal Design of a Folding-Type Hatch Cover Considering Material Selection

2021 ◽  
pp. 1-11
Author(s):  
Gerry Liston Putra ◽  
Mitsuru Kitamura ◽  
Akihiro Takezawa
Keyword(s):  
Production Systems ◽  
Material Selection ◽  
Optimization Technique ◽  
Plate Thickness ◽  
Optimization Methods ◽  
Optimization Method ◽  
Production Costs ◽  
Plate Material ◽  
Material Type ◽  
Material Cost

Abstract Most shipyard companies maintain efficiency in all aspects of their business to survive. One of these aspects is ship production costs and their reduction. This study proposes a solution to this problem using an optimization method. A hatch cover composed of plates and stiffeners was selected as a case study. In this study, the mass and material cost of the hatch cover was optimized as an objective function using the Pareto approach with developed optimization methods. Plate thickness t, stiffener shape s, and plate material type m were selected as the design variables in this study along with some constraints. To estimate the optimal plate thickness, an expression of stress equations was Developed using an optimization technique. Furthermore, stiffener shape and plate material type selection were optimized using a genetic algorithm (GA). The results show that the optimization method is effective to decrease the mass and material cost of a hatch cover. Introduction The demand for new shipbuilding has decreased because of the effect of the economic crisis that hit almost every country in the world. Shipyard companies must think innovatively and creatively to survive under the pressure of this crisis by evaluating various studies and improvising new methods to achieve efficiency. One of the studies that has been performed examines the methods to reduce the fabrication cost of ship structures to stay profitable through the optimization of work hours, workflow production systems, and structural design.

Discrete sizing, cross-sectional shape, topology optimization, and material selection of a framed automotive body

2021 ◽  
pp. 095440702110626
Author(s):  
Chao Ma
Keyword(s):  
Weight Reduction ◽  
Material Selection ◽  
Extreme Points ◽  
Optimization Method ◽  
Test Problems ◽  
Manufacturing Cost ◽  
Cross Sectional ◽  
Automotive Body ◽  
Discrete Design Variables ◽  
Sectional Shape

This study proposed a discrete structural optimization method for a framed automotive body. Up to four types of discrete design variables are considered simultaneously, that is, the sizing, cross-sectional shape, topology, and material variables. Firstly, to solve the nonconvex and nonlinear optimization problem, the original non-dominated sorting genetic algorithm, the third version (NSGA-III), is adapted. An improved extreme points identification scheme and a new mutation operator are proposed to stabilize the normalization of the population and accommodate the manufacturing constraints, respectively. Two test problems demonstrate that the modified NSGA-III can handle continuous and discontinuous multiple objective optimization. Subsequently, the classical 10-bar truss is used to illustrate the proposed method. A weight reduction of 4.5 kg is achieved as compared to previous optimal designs in the literature. Finally, a framed automotive body is optimized for maximizing the first order natural frequency and minimizing the total mass, the maximum stresses and the maximum displacements in different load cases and the manufacturing cost. The results obtained by different optimization procedures are presented and discussed. The results demonstrate the feasibility and effectiveness of the proposed method. A weight reduction of 17.59% is achieved while other structural performances satisfy the design requirements.

A Product Dissection-Based Methodology to Benchmark Product Family Design Alternatives

2009 ◽  
Vol 131 (4) ◽  
Author(s):  
Henri J. Thevenot ◽  
Timothy W. Simpson
Keyword(s):  
Product Family ◽  
Cost Savings ◽  
Production Costs ◽  
Manufacturing Cost ◽  
Successful Implementation ◽  
Product Family Design ◽  
Potential Cost ◽  
Product Families ◽  
Product Platforms ◽  
Design Alternatives

Today’s companies are pressured to develop platform-based product families to increase variety, while keeping production costs low. Determining why a platform works, and alternatively why it does not, is an important step in the successful implementation of product families and product platforms in any industry. Internal and competitive benchmarking is essential to obtain knowledge of how successful product families are implemented, thus avoiding potential pitfalls of a poor product platform design strategy. While the two fields of product family design and benchmarking have been growing rapidly lately, we have found few tools that combine the two for product family benchmarking. To address this emerging need, we introduce the product family benchmarking method (PFbenchmark) to assess product family design alternatives (PFDAs) based on commonality/variety tradeoff and cost analysis. The proposed method is based on product family dissection, and utilizes the Comprehensive Metric for Commonality developed in previous work to assess the level of commonality and variety in each PFDA, as well as the corresponding manufacturing cost. The method compares not only (1) existing PFDAs but also (2) the potential cost savings and commonality/variety improvement after redesign using two plots—the commonality/variety plot and the cost plot—enabling more effective comparisons across PFDAs. An example of benchmarking of two families of valves is presented to demonstrate the proposed method.

Mechanical Strength Analysis and Structure Improvement of Diaphragm Chamber Based on Finite Element Method

2013 ◽  
Vol 690-693 ◽  
pp. 1945-1949
Author(s):  
Xue Qin Ling ◽  
Peng Fu ◽  
Wei Zhang ◽  
Yang Chen
Keyword(s):  
Finite Element ◽  
Mechanical Strength ◽  
Production Costs ◽  
Strength Analysis ◽  
Manufacturing Cost ◽  
Long Distance ◽  
Element Analysis ◽  
Factors Affecting ◽  
Structure Improvement ◽  
Major Factors

Diaphragm chamber is the key component in fluid end of high pressure diaphragm pump for long distance pipeline transportation. Structural dimensions are the major factors affecting mechanical strength and manufacturing cost of diaphragm chamber. In this paper, diaphragm chamber was simulated by finite element analysis software ANSYS. Mechanical strength of diaphragm chamber was checked in the light of ASMEVIII-2. The structure of diaphragm chamber was modified for the purpose of extending service life and reducing production costs. The analysis results provide some theoretical guidance for research and development of diaphragm chambers and relevant products.

Effect of Membrane Electrode Assembly Bonding Technique on Fuel Cell Performance and Platinum Crystallite Size

2014 ◽  
Vol 11 (3) ◽  
Author(s):  
Steven Buelte ◽  
Daniel Walczyk ◽  
Ian Sweeney
Keyword(s):  
Fuel Cell ◽  
Phosphoric Acid ◽  
Crystallite Size ◽  
Cycle Time ◽  
Cell Performance ◽  
Membrane Electrode ◽  
Manufacturing Costs ◽  
Cell Technology ◽  
New Methods ◽  
Ultrasonic Bonding

Major efforts are underway to reduce fuel cell manufacturing costs, thereby facilitating widespread adoption of fuel cell technology in emerging applications, such as combined heat and power and transportation. This research investigates new methods for fabricating membrane electrode assemblies (MEAs), which are at the core of fuel cell technology. A key manufacturing step in the production of fuel cell MEAs is bonding two electrodes to an ionically conductive membrane. In particular, new MEA bonding methods are examined for polybenzimidazole-based phosphoric acid (PBI/PA) fuel cells. Two new methods of bonding PBI/PA fuel cell MEAs were studied with the goal of reducing cycle time to reduce manufacturing costs. Specifically, the methods included ultrasonic bonding and thermally bonding with advance process control (APC thermal). The traditional method of thermally bonding PBI MEAs requires 30 seconds, whereas the new bonding methods reduce the cycle time to 2 and 8 seconds, respectively. Ultrasonic bonding was also shown to significantly reduce the energy consumed by the bonding process. Adverse effects of the new bonding methods on cell performance and structure were not observed. Average cell voltages at 0.2 A/cm2 for ultrasonic, APC thermal, and thermally bonded MEAs were 650 mV, 651 mV, and 641 mV, respectively. The platinum crystallite size was found to be the same before and after ultrasonic bonding using XRD. Furthermore, changes in the electrode pore structure were not observed in SEM images taken after ultrasonic bonding. The test results show that it is possible to reduce manufacturing costs by switching to faster methods of bonding PBI phosphoric acid fuel cell MEAs.

Sign in / Sign up

Export Citation Format

Share Document