Compounding/Anti-Compounding Feature
'Compounding' is the simultaneous actuation of both the spring (emergency) and service brakes. Compounding can result in over-torque of the foundation brakes causing problems such as bent chamber push rods, broken camshafts, cracked drums, lining damage, damaged chamber brackets, etc.

Anti-compounding is a feature that prevents compounding and is included in all current Sealco spring brake control valves.
Terminology Index