Abstract: A circulating (kill) valve for hot, high pressure wells includes a valve assembly to be positioned in an open-ended tubular-shaped side-pocket housing of a mandrel connected into a well tubing string. The valve assembly includes an open-ended cylindrical valve body provided with an interior sealing seat and spaced-apart side openings. A valve element is arranged within the valve body and is urged by unbalanced pressures to the open or closed position depending on the direction of the pressure imbalance. In the closed position a sealing surface on the exterior of the valve element engages and seals with the lower interior sealing seat of the valve body. A ported access to the inner well string pressure permits that pressure to urge the valve element to the closed position. Such pressure may be overcome by pressure imbalance when fluid pressure exterior of the tubing string forces the valve element upwardly from its seat.

Abstract: A sealing ring assembly is disclosed for use in sealing the annular gap between two concentric cylindrical members, one of the members having an annular groove and the other member having a surface opposed to the groove. Deformable seal material and a radially expansible-contractible non-deformable split retaining ring are located in the groove, the seal material engaging one surface of the retaining ring and the retaining ring being positioned on one of the sidewalls of the groove. The seal material and the retaining ring extend radially to the surface of the other cylindrical member, the retaining ring being sized to elastically compress against that surface. The surface of the retaining ring facing the seal material is beveled or chamfered along a portion or all of its width, the beveled surface extending inwardly to the inner edge of the retaining ring.

Abstract: Well equipment such as packers, check valves, gas lift valves, sliding sleeves, side pocket mandrels, retrievable plugs and the like located anywhere in a well are protected from particles of solid debris by forming a column of a protective liquid having a density of at least about 3.0 grams per milliliter in contact with and extending above the equipment. The protective liquid serves as a barrier to prevent particles of debris having a density less than that of the liquid from settling on or around the equipment and working their way into small clearances where they may cause operational and other problems.

Abstract: A surface controlled subsurface safety valve for controlling fluid flow through a tubing string in an oil or gas well is combined with an injector valve, which is used for injecting a chemical fluid into the tubing string. The pressure exerted by the chemical fluid is used to operate both the injector valve and the subsurface safety valve. The injector valve is designed to open at an injection pressure equal to or greater than the pressure needed to hold the safety valve in its open position.

Abstract: A method for locating leaks in liquid-transporting submerged pipelines. A sonar device directs acoustic waves along the path of a submerged pipeline and the reflected waves are detected and recorded. The location of escaping liquid is then determined from the recorded reflected acoustic waves, the differences in the reflected acoustic waves resulting from the difference in acoustic impedances between the escaping liquid and seawater. Gas and/or a liquid having a different acoustic impedance from the seawater in or under which the pipeline is located may be introduced into the pipeline to enhance the detection of the liquid being transported through and leaking from the pipeline. Also, sediments stirred up by fluids leaking from a submerged pipeline and, particularly, a buried or partially buried pipeline will cause determinable differences in the recorded reflected acoustic waves. Further, the crater excavated by the escaping fluids will be revealed by the reflected acoustic waves.