Kelly cock valve

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Kelly cock valve is a constant-open type blowout protection assembly in drilling tool, as well kick happens, it can be closed and prevent fluid under ground from gushing up through the water hole in drilling column. In well control operation, if hose and high-pressure manifold is damaged, it can be replaced in safety under the valve being closes.
Upper cock adopts left hand thread but the lower adopts right hand thread, and they are identical in structure of ball valve.
Feature
Upper cock valve consists of valve body, upper/lower seat, ball body, rotary-block, retainer, spring and nonmetal seals etc.
Valve body is ASTM4140 forging, and the machinery properties after heat treatment can meet the requirement of API Spec 7.
Valve seat and ball body are made of heat-resistant stainless steel with abrasion and corrosion resistance. The valve is single direction seal, as the valve is closed, under the co-reaction of fluid pressure under well and pre-load spring pressure, the ball body approaches to the back-seat quickly so as to create a seal. As for the sealing face of back-seat adds a PTFE non-metal ring and reduce the compact of ball body to valve seat, it has more reliable performance.
The surface of the valve body stamped with visible sign of "open" or "close" indicates the open/close station of cock valve obviously.