Full-opening annulus pressure operated sampler valve with reverse circulation valve

摘要

A normally open oil well sampler valve which provides a fully open testing flow path therethrough is presented, wherein the sampler valve is closed under hydraulic control after a predetermined pressure increase in the well annulus pressure. The sampler includes two spaced apart ball valves having a sample chamber therebetween. The operating mechanism moves the ball valves from the open to the closed position simultaneously, and provides a hydraulic lock as well as a mechanical lock to prevent the balls from reopening in the well. The apparatus further includes a circulation valve which is opened after the closing of the sampler valve. One of the ball valves of the apparatus may be selectively removed to provide a single ball, safety closure valve when a well fluid sample is not desired.