Humphrey developed a custom valve manifold assembly with virtually zero leakage for a customer building test equipment that could detect and calculate exceptionally low leak rates in a variety of products.
The units are designed to detect pressure changes to 0.00001 PSI, then calculate the leak rate. Selected manifold assemblies were subjected to 200,000 cycles, and every 50,000 cycles the customer ran a precision leak test. On every test the pressure drop due to leaks was less than 0.002 PSI over 30 seconds at 100psi – the equivalent of a 0.0025 scc/min flow rate. This exceeded the customer’s specification by a factor of twenty.