Abstract: A seal assembly is provided for use in a fluid flow conduit, and includes a valve seat and a valve plug. The valve seat includes a seating lip formed at least in-part of yieldable material. The valve plug is passed through the fluid flow conduit and caused to sealingly engage the valve seat. Together the valve seat and valve plug form an obstruction to the passage of fluid within the fluid flow conduit, and pressure is developed upstream. At a predetermined pressure level the valve deforms the valve seat, and is passed therethrough. A larger valve plug can be passed until it seats against the enlarged valve seat. The pass-through process can be repeated.

Abstract: In order to provide safety in a borehole communicating in particular with a cavity washed out from rock salt and containing gas under pressure, the prior art provides devices suffering from the drawback of reducing the flow sections through the tubes in the borehole. The present invention minimizes this section reduction by means of a hollow cylindrical sleeve closed inside by a plug and including ducts formed in its wall in such a manner as to cross over the flows of fluid taking place respectively in a central tube of the borehole and in the annular space between the central tube and a peripheral tube. In one embodiment of the present invention, the sleeve is sandwiched between portions of the central tube and of the peripheral tube, with safety valves advantageously being mounted on the portions of central tube above and below the sleeve.

Abstract: In the area of oilfield wellhead equipment and well servicing, specifically the operations associated with the prevention of fluids and gases from escaping from the well when valves and associated equipment which normally control the flow of these fluids and gases have been removed for repair or for any other reason, the installation of and removal of a plug in the top of the tubing hanger is a common and necessary operation. This plug is commonly called a back-pressure plug and is a standard throughout the industry. A tool is proposed for installing and removing this plug while the well is under pressure, which tool will indicate that the plug is properly in place and will also overcome the operational problems associated with existing tools and the overall height associated with existing tools.

Abstract: A subsurface well safety valve having a curved flapper closure member and method making. The curved flapper has a concave sealing surface coacting with a valve seat. A flow tube has a lower end contoured to the flapper sealing surface. A flapper can be made out of a tubular member in which the inside has been honed providing a flapper with a concave surface which forms a sealing surface.

Abstract: A sliding sleeve casing tool installed in a casing string comprising a housing, sliding sleeve, seal members and releasable retaining means to retain the sliding sleeve within the desired locations with the housing.

Abstract: A pilot valve system for a subsurface safety valve operated by control fluid pressure from the surface including a pilot valve connected with the control fluid line to the subsurface safety valve and into the well production string immediately above the safety valve to bypass the control fluid pressure directly into the tubing string and dump the control fluid pressure from the subsurface safety valve into the tubing string directly above the valve to minimize the time delay between control fluid pressure reduction and the safety valve closure. Three embodiments of the pilot valve are disclosed. One embodiment is operable by electrical energy from the surface. The other embodiments are operable by acoustic energy and radio waves, respectively. Also disclosed is a minimum backlash latch assembly for releasably locking the pilot valve, or other well tools, along a well bore in a receptacle such as a side pocket mandrel.

Abstract: Safety equipment for land or marine well completions is disclosed. In one embodiment of the invention a gate valve is provided in which the gate has a removable insert so that in one position of the valve, the insert can be removed (or inserted) via an upper vertical passage of the valve to provide full-bore access via an attached blowout preventer stack to the well head below.In another embodiment of the invention a gate valve is provided having at least two vertical passages through the gate. The first is large enough to provide full-bore access via an upper passage in the housing of the valve. The second is of a smaller diameter to provide vertical communication with tubing disposed in a lower vertical passage and in an upper vertical passage.Either of the above embodiments may be used in a lateral production tree where the gate is provided with an "L" or "T" shaped passage in another lateral portion of the gate and lateral outlets are provided in the valve housing.

Abstract: This invention relates to equipment which is installed in oil wells and more particularly to a tool control apparatus for a tool placed in the production string of a well.This apparatus is lowered into the well at the end of a cable (116). It comprises a first mechanism (134-148-152-154) for transforming a longitudinal reciprocating movement into an alternating rotary movement, the longitudinal movement being obtained by pulling on the cable (116), and a second mechanism (156) forming part of the first, for transforming the alternating rotary movement into a one-directional rotary movement.The invention also relates to an apparatus for closing the production string of a well, characterized in that it includes the closing apparatus or plug involved.Application to oil well production tests.

Abstract: A safety valve is disclosed which may be installed on an offshore wellhead above the tubing head and below the Christmas tree. The valve has a housing with upper and lower vertical passages and a lateral housing passage. A cylindrical gate is disposed within the lateral passage and includes a "T" shaped passage therein. The gate may be moved laterally and angularly within the lateral passage. During completion or workover of the well, the gate is moved laterally until the upper and lower vertical passages are in full open communication to run drills, hangers or other large diameter devices into the well via a BOP which may be attached to the top of the housing. During normal production, the gate may be laterally moved into the intersection of the vertical and lateral passages and the small through head part of the "T" passage serves to provide a vertical flow path through the production bore which is sealed off from the larger upper and lower vertical passages.

Abstract: In an injection well for underground gasification of carbonaceous materials, either liquids or solids, by partial combustion with oxygen-rich gas in the presence of a moderating fluid such as steam, air, CO.sub.2 or the like, in which the moderating fluid is introduced through an annular path surrounding the injection tube through which the oxygen-rich gas is injected, back flow of gasification products from the well is prevented by providing a flow restriction in the annular path to increase the linear flow velocity of the moderating fluid while maintaining the designed mass flow rate of said moderating fluid. The flow restriction is so designed that at the predetermined downward flow rate of said moderating fluid the critical velocity of the moderating fluid at the restriction corresponds to the formula:V.sub.c =.sqroot.gDwherein g is the gravity constant, D is the equivalent diameter of the largest opening in the restriction.

Abstract: A special tool for use in fishing operations during well drilling when a so-called string shot is used. The tool is made up of a hollow sub that may be connected into a string of pipe for lowering in the well. And, it includes a sliding sleeve in the sub. There is a gate in the wall of the hollow sub that is held in place by the sliding sleeve so as to leave the hollow sub open when a preliminary fishing opertion is attempted. And, there is means associated with the sleeve for sliding it to a different position so that the gate will be shifted in order to guide a string shot to the outside in case the inside of the fish is plugged.

Abstract: Hollow tubular members used as piling to support offshore platforms and the like are more easily aligned with a stabbing means. The base of the stabbing means is flexibly attached to the inner surface of one end of a tubular member; the tip of the stabbing means, which is rounded and pointed, projects beyond the end of the tubular member. The stabbing means can be attached to the tubular member for easy removal and can be adapted to couple with a retaining device within a companion tubular member that is to be aligned with the first tubular member. Preferably, a cable is coiled within an elastomeric material that flexibly bonds the stabbing means to the tubular member--the cable can be pulled or ripped from the material to destroy the bond and thereafter permit removal of the stabbing means.

Abstract: An injection assembly includes a packer set in the casing adjacent to the producing zone, having a bore sized to receive production tubing. A portion of the assembly suspended from the string of production tubing includes a side pocket mandrel, a twin flow head, an extensible telescoping housing, and coacting joint means on the extensible housing and the packer for axial joining of these members. The side pocket mandrel, twin flow head, and twin flow converter provide a first passage joined to the production tubing; and a length of inner tubing joined to the twin flow converter extends this passage down into the bore of the packer.

Abstract: A well tool such as a multiple string tubing hanger is installed remotely with the aid of a handling tool which has a hydraulically actuated component and a locator device movable between a retracted inactive position and an extended position in which the locator device engages in a locator slot in a surrounding member to orient the well tool in a predetermined rotational position relative to the surrounding member, a pressure fluid conduit of the handling tool being connected to the hydraulically actuated component and a valve associated with the locator device in parallel so that full pressure on the hydraulically actuated component cannot be built up except when the locator key is in its extended position.

Abstract: A well testing tool system for isolating vertically spaced portions of a well bore and measuring well conditions such as pressure, and temperature. The system includes a wireline supported tool train and a locking sub connectible on a removable lock mandrel for releasably locking the tool train in a well bore. The tool train has a locking probe releasably connectible in the locking sub, a probe mandrel connected with the probe, an equalizing valve and shock absorber, and a gauge for measuring an operating condition in the well. The locking sub permits insertion of the probe at a low force and requires a larger force for withdrawal. The locking sub grips the probe with a force directly proportional to the pressure differential across the locking sub. The equalizing valve and shock absorber provides for pressure equalization across the tool train during handling and absorbs shock to protect the measuring device. Two forms of the valve and shock absorber are spring biased open.

Abstract: A sleeve valve which may be made up as a part of a tubing string in which the valve member has two positions. Dogs carried by the valve member alternately cooperate with spaced grooves in the body in said positions. The dogs are alternately engageable by a shifting tool to shift the valve member in opposite directions and after the valve member has been shifted, the dogs are disengaged from the shifting tool. The valve is disclosed as a part of a testing system employing a circulating tool, a cushion valve, a seal unit, and a landing nipple with a transducer fitting.

Abstract: A fail-safe sub-surface safety cut-off valve for fluid wells controllable from the surface and suitable for installation at substantially greater depths than prior constructions. The valve assembly is installable and retrievable via wire line technique and utilizes an electromagnetic means to operate either a flapper or a ball cut-off valve. The operating solenoid coil embraces a landing nipple portion of the tubing string and is outside the production flow. This solenoid supplies the power to open either type of cut-off valve and holds the latter open only so long as the solenoid is energized thereby providing surface control of the safety cut-off valve normally and assurance of closing of this valve in the event of power failure through accident or some catastrophe as well as automatic closure if flow velocity increases beyond a predetermined safe value.