Abstract: A plug is disclosed for sealing off in a tubing having a sealing surface. A housing contains an annular metal seal means and two sets of segmented expanding lockdown rings that react with three solid rings to provide a downward motion. The expanding lockdown rings consist of a solid tapered ring that has been cut into a number of arcs. When a tapered mandrel is forced down inside the arcs, the arcs are expanded to the outside diameter of the mandrel. As the arcs expand, they are wedged between the solid rings that have matching tapers. The solid rings react between locking dogs and a shoulder in the housing to provide the downward movement. By using several expanding lockdown rings and solid rings, a relatively great deal of vertical motion can be obtained through the combined wedging action of each ring. Means on the housing and the tubing may be used to limit the locking load on the annular seal means.

Abstract: Method and apparatus are disclosed for recovering submerged equipment, such as a guide base and wellhead used in offshore well operations. A recovery tool, which includes an elongated member capable of extending from above the equipment into a well pipe and means for latching the recovery tool to the equipment and explosive means attached to the elongated member for severing the well pipe, is lowered from the water's surface to the equipment and then latched thereto. The explosive is then detonated to sever the well pipe. The recovery tool, together with the equipment and severed portion of the well pipe, is raised to the water's surface.

Abstract: A method for use in connecting flanges of a tubular joint is disclosed. A uniform pressure is applied to the flanges of the joint up to a desired preselected, measurable compression after which the nuts and bolts used to secure the flanges together are made up hand-tight. The preselected compression applied to the flanges is then released.

Abstract: In a method for producing hydrocarbon gas from aquifers which contain gas in water solution, water is produced from wells distributed through the aquifer and solution gases are recovered from the produced water. The aquifer pressure declines as production continues; gas comes out of water solution and a gas phase saturation builds up in the aquifer. When gas saturation exceeds a critical value, gas in gaseous phase flows through the aquifer rock to the producing wells and the ratio of total gas to total water produced increases substantially.

Abstract: A device is disclosed for restraining lateral movement of large underwater equipment, such as a blowout preventer (BOP) stack for use on subsea wells, when retrieving or running such equipment through the well of a floating vessel. A plurality of rollers are angularly positioned about the well, each roller being capable of rolling longitudinally (vertically) along the equipment. Each roller is connected to shock absorbers for cushioning lateral movement of the equipment and to a piston cylinder for moving each roller toward and away from the equipment.

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.