Standard

 

MCA 230 – Mold Design I

Course Description

Introduces instruction in the design, construction, selection, safe use, and maintenance of molds and equipment. Emphasizes mass production of plastic articles and die cast molds for aluminum and zinc alloys. Topics include: types of plastics; types of molds; mold components and functions; design of runners, gates, and venting systems; and shot and production calculations.

 

Competency Areas

Hours

 

Types of Plastics

Class

5

Types of Molds

D. Lab

0

Mold Components and Functions

P. Lab/O.B.I.

0

Design of Runners, Gates, and Venting Systems

Credit

5

Shot and Production Calculations

 

 

 

 

 

Prerequisite/Corequisite:

MCA 226, MCA 233

 

Course Guide

 

Competency

After completing this section, the student will:

Hours

Class

D.Lab

P.Lab/

O.B.I.

TYPES OF PLASTICS

10

0

0

Thermosetting vs. thermoplastic

Explain thermosetting and thermoplastics.

 

 

 

 

Divide lists of polymers into thermosetting and thermoplastics and then into categories of raw materials.

 

 

 

 

List specific plastics and the physical properties (e.g., thermo properties, hardness, cold flow, and permeability).

 

 

 

 

Discuss plasticizer, fillers, stabilizers, and reinforcing agents.

 

 

 

 

Discuss addition polymerization and condensation polymerization.

 

 

 

 

Describe monomers, dimers, bi-functional monomers, poly-functional monomers, crosslinked pendant groups, tacticity, isotactic, syndiotactic, and atactic.

 

 

 

Application

Identify types of plastic samples.

 

 

 

TYPES OF MOLDS

15

0

0

Elements of mold design

Describe types and selection of plastic materials.

 

 

 

 

Describe compression, injection, and transfer mold design and operation.

 

 

 

MOLD COMPONENTS AND FUNCTIONS

10

0

0

Theory

Describe parts of mold and mold functions.

 

 

 

 

Explain the methods available to introduce plastic into molds.

 

 

 

 

Explain the parts of common plastic mold types and describe how they are produced.

 

 

 

 

Describe injection molding, vacuum forming, and blow molding setup.

 

 

 

DESIGN OF RUNNERS, GATES, AND VENTING

5

0

0

Flow pattern

Explain the purpose of a gating system.

 

 

 

 

Describe gating system fundamentals and the path material follows from the source mold cavity.

 

 

 

 

Define sprue, runner, gates, and vents.

 

 

 

 

Explain the relation among runners, gates, and vents.

 

 

 

SHOT AND PRODUCTION CALCULATIONS   

10

0

0

Calculations

Explain method for calculating projected area, volume, and piece part weight.

 

 

 

 

Explain the impact of the number of cavities on production.

 

 

 

 

Discuss the impact of piece part shrinkage on mold design.

 

 

 

 

Explain the importance of a uniform wall thickness on a piece part.

 

 

 

 

Suggested Resources

 

Books

 

Allyn, E. (1987). Mold design I: For plastic injection. Woodstock, NY: Allyn Air.

Bhattacharya. (1987). Metal-filled polymers: Properties and applications. New York: Dekker.

Birley, A. W., et al. (1988). Plastics materials: Properties and applications (2nd ed.). New York: Chapman & Hall.

Brown, R. L. (1980). Design and manufacture of plastic parts. New York: John Wiley & Sons.

Calvert, E. (1980). Injection moulding. Philadelphia: Trans-Atl Phila.

Chkeremisinoff. (1989). Handbook of polymer science and technology: Performance properties of plastics and elastomers (Vol. 2). New York: Dekker.

DuBois, J. H., & Pribble, W. I. (1987). Plastics mold design engineering handbook (4th ed.). New York: Van Nos Reinhold.

Dym, J. B. (1987). Injection molds and molding (2nd ed.). New York: Van Nos Reinhold.

Epstein, G., & Schwartz, S. (Eds.). (1985). Mold design and moldmaking for plastics products. New York: T-C Pubns CA.

Gastrow, H., & Stoeckhert, K. (1983). Injection molds: One hundred two designs. New York: Oxford University Press.

Glanvill, A. B., & Denton, E. N. (1965). Injection-mould design fundamentals. New York: Industrial Press.

Isayev, I. A. (1987). Injection and compression molding fundamentals. New York: Dekker.

Johannaber, F. (1983). Injection molding machines: A user's guide. New York: Oxford University Press.

Menges, G., & Mohren, P. (1986). How to make injection moulds. New York: Oxford University Press.

Nyborg, R. L. (1990). Plastic injection molding made easy. Provo, UT: Regal Pubns.

Robinson, J. S. (Ed.). (1981). Plastics molding: Equipment, processes, and materials. Lake Mary, FL: Polymers and Plastics Tech Pub.

Rosato, D. V., & Rosato, D. V. (1985). Injection molding handbook. New York: Van Nos Reinhold.

Rosato, D. V., & Rosato, D. V. (Eds.). (1989). Blow molding handbook. New York: Macmillan.

Schwartz, S., & Goodman, S. (1982). Plastics materials and processes. New York: Van Nos Reinhold.

Society of Plastics Engineers Staff. (1985). Tooling challenges for the 80's: Injection molding tooling: Design, materials, methods. New York: Bks Demand UMI.

Sors, L. (1981). Plastics molds and dies. New York: Van Nos Reinhold.

Sors, L., & Balazs, I. (1989). Design of plastic moulds and dies. New York: Elsevier.

Stoeckhert, K. (1983). Mold-making handbook: For the plastics engineer. New York: Oxford University Press.

T-C Pubns CA. (1981). Proceedings of SPE Pactec '81, August 25-27, 1981, Los Angeles, California. New York: Author.

T-C Pubns CA. (1983). Foams: Molding thermosetting and thermoplastic structural foam. New York: Author.

T-C Pubns CA. (1983). Injection molding-plastics. New York: Author.

T-C Pubns CA. (1984). Injection molding machinery and accessories, 1976-January 1985. New York: Author.

T-C Pubns CA. (1984). Injection molding of plastics. New York: Author.

T-C Pubns CA. (1984). Mold release agents for rubbers and plastics, 1973-1986. New York: Author.

T-C Pubns CA. (1984). Reaction injection molding of polymers. New York: Author.

T-C Pubns CA. (1985). Machining processes and properties of plastics and elastomers, 1973-April 1985. New York: Author.

Tobin, W. J. (1985). Quality control manual for injection molding. New York: T-C Pubns CA.