UHMWPE has a thermal expansion rate of 150-230 x 10-6 m/m.K, but as a Rule-of-Thumb, 1m of UHMWPE expands approximately 2mm for every 10o C increase in temperature. If the thermal expansion is not accounted for in the design, UHMWPE Wear Strips can buckle as illustrated in the below image.

Design Considerations

The most important thing when designing for thermal expansion is to allow the expansion to occur, and not try to restrain it. This can be done by

1.       Allowing for movement at the fastener.

As illustrated below, having an oversized hole and a generous washer.

2.       Leaving a gap between wear strips to allow for thermal expansion

Below are a couple of options on how to achieve this.

The size of the expansion joints and the clearance for the fasteners can vary based on the temperature changes and the length of the parts. For technical support in this area please feel free to contact your local Dotmar office or one of our engineers.

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