The artificial intelligence (using an ANN) was also used by Wang et al.[4] to develop a cost model for the mold manufacturing, including variables such as tax costs and general administrative costs. Case representation, case retrieval, case indexing, case adaptation and the case learning mechanism are also studied in detail.
Gupta [5] has at his personal website an interesting study on single and multi-material molding cost. For the single material case, Gupta proposes the use of Bryce’s empirical method, Rosato’s Method, Boothroyd’s Method, Poli’s Method and Kazmer’s Method. He explains all those methodologies as well. On the other hand, the cost analysis made to the multi-material molding is exhaustive, and Gupta uses a model that considers input variables (CAD model and company specifications) and as output data shows a graph that compares the quantity vs. the cost.
3. Programs
In this short contribution, we show a total of 5 programs that can be useful to achieve good cost estimation for the injection molding process. The main characteristics and/or features of each of them are also described.
Injection Molding Cycle Time Estimator (Freeware).
The license of its calculator software is also free. The purpose is to calculate cycle times, that can be used for a rough cost estimation. It’s a very simple software, and has the following features:
1. Different estimation data based on resin type.
2. Allows machine setting overrides for temperatures.
3. Two types of estimation methods (centerline and average cooling of wall stock).
4. Easy Windows Forms interface.
5. Error Checking
ProMax-One™ PLASTIC PART COST ESTIMATOR (InjectNet).
This is also a free option. It calculates the total cost per part and can show a breakdown window with the detail of all cost results. It considers the materials used, project information, labour, mould cost, machinery, maintenance, cavity information, etc.
The Plastic Part Cost Estimator is more complete than the Injection Molding Cycle Time Estimator Freeware.
CostMate® (IDES Inc.).
Costmate is a moulding part cost estimator that have been integrated into an online plastics search engine (Prospector®). The basic version of this engine is free.
Costmate considers costs due to shipping and packaging as well.
DFM Concurrent Costing® (Boothroyd Dewhurst, Inc).
This is a commercial cost software designed mainly for the design stage. It’s possible to customize the cost estimate by changing the defaults and entering a new part geometry and other variables from the own injection molding machine.
This software also includes a geometry calculator. It gives the possibility to compare alternative processes and materials for the piece manufacturing.
CalcMaster® Software (Schouenberg & Partners).
CalcMaster is a powerful program that can be used not only as a cost estimator but also as a good design assistant.
It calculates the most economical number of cavities, and takes into account the project hours cost (design and manufacturing).
4. Conclusions
Despite the low number of programs described above, results indicate that the paid software options are more accurate and offer more options for make decisions on which is going to be the final cost of manufacture an specific piece using an injection molding machine.
The free software options are more restrictive in considered variables. ProMax-One™ can be a good choice, since it makes calculations on several parameters, such as the cavity data and project information.
References
[1] Chen, Y-M., Liu, J-J. Cost-effective design for injection molding. Robotics and Computer-Integrated Manufacturing, 1999; 15 (1): 1-21 注塑模制工艺英文文献和中文翻译(2):http://www.youerw.com/fanyi/lunwen_40879.html