Pressure Cracking Leak Test

What is a Pressure Cracking Leak Test?

A crack test is used to find the opening pressure of a check valve or similar item. The crack test is similar to the burst test, in that it detects an event such as a valve opening. It is especially useful in testing devices that have a small amount of weep (small leak) before the full opening. The test is performed across two ports, with the inlet of the device on port one (sensor 1) and the outlet of the device is connected to port two (sensor 2). The pass/fail limit is set as a min/max pressure value of the pressure required to open the device. The ‘trigger’ is the amount of pressure increase on the output side that constitutes an opening of the device. Sensor two can be either a pressure transducer or a mass flow transducer depending on the needs of the application.