Abstract: A self-releasing hook comprising the following basic elements: a hook body having a slot to receive a load ring or the like and a crotch in which the load ring rests when loaded, a plunger for raising the load ring out of the crotch in the hook body, a latch for holding the loaded hook ring within the slot at least prior to loading, a spring for urging the plunger to the ejection position and another spring biasing the latch in a position blocking exit from the slot. The slot is shaped to receive the load ring and permit the latch to return to a latching position while the plunger is in the ejecting position.

Abstract: The mechanical strainer unit is connected to a flanged conduit which originates in and extends out of a suppression chamber in a nuclear reactor. The strainer includes a plurality of centrally apertured plates positioned along a common central axis and in parallel and spaced relationship. The plates have a plurality of bores radially spaced about the central axis. Spacer means such as washers are positioned between adjacent plates to maintain the plates is spaced relationship and form communicating passages of a predetermined size to the central apertures. Connecting means such as bolts or studs extend through the aligned bores to maintain the unit in assembled relationship and secure the unit to the pipe. By employing perforated plates and blocking off certain of the communicating passages, a dual straining effect can be achieved.

Abstract: A strainer is provided for removing particulate debris from a fluid passing therethrough. The strainer is primarily of the automatic type having a hollow body, a cover, a strainer element and a backwash arm assembly for cleaning the strainer element. The strainer element is a cylindrical, convoluted screen having encapsulating end caps positioned at either end. The end caps and thus the strainer element are retained so as to avoid rotation in seal rings, one of which is connected to the cover and the other of which is detachably connected to the terminus of the backwash arm. The strainer element is a structural member capable of withstanding the loads imposed on it by the fluid.

Abstract: A strainer of the self-cleaning type includes a strainer element capable of removing matted debris by backwashing. The strainer element comprises a plurality of stacked annular strainer plates maintained in spaced relationship to form straining passages wherein the passages are substantially greater in depth than height. Protruding surfaces of the strainer element form vertically aligned compartments along its upstream side. The compartments collect the debris. A rotating backwash arm or arms are provided which may carry at least one cutting blade. The blade cuts matted debris extending between compartments into sections as it passes over these protruding surfaces and these sections are removed by backwashing.