Sealing Class

There are six different seat leakage classifications as defined by ANSI/FCI 91-2-2001 and the table below.

All Clark Cooper valves are 100% tested prior to shipment and our leakage test is based on the requirements of the FCI specification.

Class I is intended for metal to metal seals. Class II is intended for a general production test on a valve with elastomeric seals and is the standard for our EH30, EH40, EH50 and EH70 valves. Because our ER valves utilize an elastomeric seal on the main piston disc but a metal to metal pilot, we test for a leakage class halfway between Class I and Class II as shown in the table below.

If your application requires a tighter leakage requirement (bubble tight), our optional Class V testing can be used. This option requires a more stringent test often accompanied with manual polishing of the seat to achieve the leakage requirement as outlined in the table below.

If Class V is not enough for you then we can always use the Class VI option with your supplied leakage requirements and modify the valve materials or design to meet your applications needs. Please contact us for all Class VI inquiries.