Abstract: Surface packer and method for using the same. An annular body is mounted on the upper end of a string of casing which extends above a drilling rig platform. An annular seal is received within the body at the upper end thereof and may be sealed against the radially outer surface of a string of drill pipe which is lowered therethrough into the casing. A radial circulation port is formed in the body beneath the annular seal. In a cementing operation, a string of drill pipe is lowered in the casing to the lower end thereof and the annular seal is sealed thereagainst. The pipe-casing annulus is pressurized and cement is pumped into the drill pipe for cementing the casing into the well bore. In one embodiment, the annular seal is of the inflatable type which permits vertical and rotational manipulation of the pipe string while maintaining the seal thereagainst.

Abstract: A cementing tool includes a tubular housing having a cementing port disposed through a wall thereof. An upper adapter has its lower end connected to the tubular housing, and has a second end adapted for connection to a string of pipe. A sliding sleeve valve assembly is located within the tubular housing and is slidable relative thereto between an open position wherein said cementing port is open, and a closed position wherein said cementing port is closed. A protective sleeve has its lower end connected to the sliding valve sleeve assembly and has its upper end slidingly received within an inner cylindrical surface of the lower end of the upper adapter. The protective sleeve is always received within said cylindrical surface of the upper adapter so that it always covers a gap between the lower end of the upper adapter and the sliding valve sleeve assembly, thereby preventing any device which is passed through an inner bore of the cementing tool from entering said gap and hanging up thereon.

Abstract: 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.

Abstract: A releasably locked closed circulation valve is introduced into a well bore as part of a drill string. The annulus between the drill string and the well bore, or casing affixed to the well bore, is sealed. Pressure is applied to the annulus and the valve unlocks and opens once the annulus pressure reaches a certain level to allow circulation between the annulus and the interior of the drill string. An optional locking device preferably locks the opened valve in the open position. A second embodiment includes a tester valve simultaneously operable with the circulation valve.

Abstract: A releasably locked closed circulation valve is introduced into a well bore as part of a drill string. The annulus between the drill string and the well bore, or casing affixed to the well bore, is sealed. Pressure is applied to the annulus and the valve unlocks and opens once the annulus pressure reaches a certain level to allow circulation between the annulus and the interior of the drill string. An optional locking device preferably locks the opened valve in the open position. A second embodiment includes a tester valve simultaneously operable with the circulation valve.