Abstract: A transportable, remotely actuated racking device is provided for use in connection the insertion and removal of very high voltage industrial circuit breakers. The device includes a motor activated rod assembly which is moved between first and second positions for grasping of the circuit breaker during insertion and removal from the circuit breaker housing. The racking device is remotely operated from a point of safety relative to the circuit breaker whereby direct exposure to possible fire and explosions which might occur during racking is greatly reduced.

Abstract: A locking piston drive system and valve assembly is provided for shutdown of a nuclear reactor. "Chatter" in a check valve assembly which occurs during charging and/or re-charging of control fluid within a control line is eliminated by providing a valve head and a resisting portion defined on the valve head to resist movement of the valve head when it is urged from sealing engagement on its seat during the charging or re-charging procedure.

Abstract: A locking piston drive system and valve assembly is provided for shutdown of a nuclear reactor. "Chatter" in a check valve assembly which occurs during charging and/or re-charging of control fluid within a control line is eliminated by providing a valve head and a resisting portion defined on the valve head to resist movement of the valve, head when it is urged from sealing engagement on its seat during the charging or re-charging procedure.