Cap low leak testing system

摘要

A method is provided for accurately determining the volume of gas that has leaked through and around a cap having a mouth and a seal situated about the circumference of the mouth. The method includes the steps of positioning the cap within a testing neck on a fuel cap testing apparatus, fixing the cap in the neck to create a general sealing engagement between the seal and the neck and to cause the seal to move into the neck, and "staging" the cap for at least 2.5 seconds. Staging refers to the necessary waiting period that must pass in order to allow the seal to complete moving into the testing neck. A test is then conducted for changes in pressure within the testing neck due to low-volume gas leaks through and around the cap.