Meaning
Geometric change in polymer components over time occurs due to internal stress relaxation and environmental absorption. Manufacturers track elastomeric dimensional drift to ensure that seals and gaskets maintain their sealing force throughout the service life of a product. This measurement stops being relevant once a material reaches a state of total chemical degradation or physical failure.
Material Instability
Internal stresses trapped during the injection molding process gradually release as the part ages. The resulting elastomeric dimensional drift causes parts to shrink or expand away from their nominal design specifications.
Production Tolerance
Engineering teams set wider acceptable ranges for flexible parts compared to rigid steel components. Because elastomeric dimensional drift is predictable based on temperature and humidity, designers often oversize a part to account for future shrinkage. This practice ensures a tight fit during the middle of the product lifecycle.
Quality Impact
Verification of part size happens at specific intervals after production to confirm the rate of change is within limits. If elastomeric dimensional drift exceeds the forecast, the batch is rejected to prevent leaks in the final assembly. Such failures cost more to fix in the field than at the factory gate.
This data informs the final readiness of the product for mass production.
