CONVERSION OF AN OBSOLETE MANUALLY OPERATED UNIVERSAL TESTING MACHINE INTO A HYDRAULIC HOT-PRESS WITH COMMUNICATIONS CAPABILITY

摘要

The improvement of outdated laboratory equipment is a useful and often overlooked resource that has several advantages. One obvious advantage is that it saves money by adding new capability and reducing capital expense for newer equipment. Another advantage is the honing of skills by the people who make the improvements. Yet a third advantage is the example and inspiration that stimulates others to put forth other ideas for improvement. The importance of constant improvement was expressed by the renowned statistician and quality advocates. W. Edwards Deming one of whose 14 points is "Constantly and forever improve the system of production and service". The concept of constant improvement has been captured by the Japanese in the word kaizen and used by them to bring their automotive and other industries to world class status from the ashes of defeat in World War II. When the need arose for a hot press to mold precision polymer laminates the obvious response was to determine how much a new press would cost. The new press would have to heat the laminates to 175°C, measure the force necessary to apply pressure of 1.0 MPa, and communicate with a computer that could acquire and store the information for further analysis. A widely used and well developed laboratory press was available that would satisfy the heating requirement but not the force measurement and communication requirements. The cost of the press plus the addition of force measurement and communication capabilities was estimated to cost in excess of USD10,000. This was a capital expense that could be reduced by converting and upgrading an existing piece of equipment. Upon the acquisition of a new computer controlled material testing machine, the existing obsolete hydraulic testing frame was rendered useless. The tester was nearly four decades old with a single non-functioning Bourdon tube pressure gage. So the decision was made to transform the existing manually operated tension and compression materials tester into a hydraulic hot press with symmetric and uniform heating zones and communication capabilities. The expectations were that the improvements of existing equipment were not only cost effective but also would provide the other advantages noted above. The original manually operated hydraulic cylinder and load frame were in good condition and were retained. Once converted, the now-functioning compression hot press was calibrated and characterized according to its temperature range and stability, pressure range and stability, and the geometric and thermal symmetry of the platens. The total cost of conversion of the unit was around USD3300.00. The results of the project are reported here.