Date of Award


Degree Name

Master of Science


Industrial and Entrepreneurial Engineering and Engineering Management


Industrial and Manufacturing Engineering

First Advisor

Dr. Paul Engelmann

Second Advisor

Dr. Betsy Aller

Third Advisor

Dr. Philip Guichelaar

Access Setting

Masters Thesis-Open Access


The non-return valve has been a standard piece of equipment in the injection molding industry since the reciprocating screw was developed. Most molders understand the role of the non-return valve in the molding process. But few understand the functional problems of the non-return valve. Because of this, the non-return valve has been considered a nuisance item for injection molders.

Wear of the non-return valve is another problem that molders are faced with. The factors contributing toward wear are not entirely understood. Material, temperatures, hours and machine size, etc., all effect the life of a valve. Consequently, most worn valves are not discovered until there is a problem during molding. The molder must either adjust the process or shut the machine down for unscheduled maintenance. Therefore, a methodology for establishing predictive maintenance guidelines would be beneficial.

This methodology will give the molder a practical guide for specifying, evaluating, and maintaining non-return valves.

Included in

Manufacturing Commons