Abstract: A heat releasable weldment for a mechanical opening jack used in combination with fluid powered valve actuators to release said manual opening jack in the event of fire comprising grooved inner and outer members which cooperate to form a eutectic chamber, said inner and said outer members being retained in spaced relationship with each other by horizontal and vertical restraining members in cooperation with a fusable eutectic alloy which is poured into said eutectic chamber and allowed to solidify together and a method to field retrofit said weldment to a mechanical opening jack is presented.

Abstract: A heat releasable weldment for a mechanical opening jack used in combination with fluid powered valve actuators to release said manual opening jack in the event of fire comprising grooved inner and outer members which cooperate to form a eutectic chamber, said inner and said outer members being retained in spaced relationship with each other by horizontal and vertical restraining members in cooperation with a fusable eutectic alloy which is poured into said eutectic chamber and allowed to solidify together and a method to field retrofit said weldment to a mechanical opening jack is presented.

Abstract: A cylinder for a valve actuator wherein the cylinder body has lugs connectable to and disconnectable from like cylinder head lugs by less than one turn rotation. Resilient seals seal the head to the body when connected, and the connection is releasably lockable.

Abstract: A cylinder for a valve actuator wherein the cylinder body has lugs connectable to and disconnectable from like cylinder head lugs by less than one turn rotation. Resilient seals seal the head to the body when connected, and the connection is releasably lockable.

Abstract: A portable add-on actuator module for use with a wireline cutting surface safety valve to provide supplemental energy for closing and simultaneously cutting a wireline extending through the surface safety valve in the event of an emergency. The unit includes a spring loaded locking collet assembly arranged to engage a locking recess within the stem of a surface safety valve so that the spring force may be added to normal valve closing forces such as line pressure and valve stem springs to supplement such forces for insuring the cutting by the surface valve member of a wireline extending through the member. The actuator module has a body which rests on the safety valve body without the use of any connecting structure. The module also includes structure for hydraulically compressing the spring for connecting the module on a safety valve and for hydraulically shifting the latching collet assembly to a disengaging condition for releasing the module from a safety valve.