SAE J1638_201504

This SAE Recommended Practice is used for establishing the compression set that could be expected to occur with engine coolant hoses under securing clamps. It seeks to reproduce the type of indentation caused by the clamps in the wall of the hose. An excessive compression set measured by this method would indicate a hose that could eventually alloy leakage of coolant past the clamps in service. This method has been found to give repeatable results in the range of 25% to 50% initial compression.