Abstract: A floating apparatus for use in a casing string. The apparatus includes an outer sleeve having a check valve centrally positioned therein. A body portion, which may be comprised of high compressive strength cement, is affixed to the check valve and the housing. The body portion has an upper end and a lower end. An upper seal is disposed above the upper end of the body and sealingly engages the housing and the outer sleeve. A lower seal is disposed in the sleeve below the lower end of the body portion, and sealingly engages the valve housing and the outer sleeve, so that fluid flowing through the outer sleeve cannot communicate with the body portion.

Abstract: A fill valve includes a tubular housing which accommodates a valve member which is biased toward a closed position by a light spring. The valve member includes a head and a tubular portion which is provided with two large windows. When the fill valve is open fluid flows freely through the tubular portion of the fill valve and out of the windows.

Abstract: Insert type floating equipment valves for use in the cementing of casing in oil and gas wells and the like which may be retained in the casing therein through the use of slips or set screws or anchors and uses either cup type or compression type sealing members.

Abstract: A gravel pack screen assembly includes a bit or sub having a flow passage which may accept a wash pipe. The wash pipe may be inserted past a flapper-type closure member which moves to a closed position upon withdrawal of the wash pipe after completion of the installation of the gravel pack assembly. The closure member can be formed of a porous material to permit the flow of liquid through the bit or sub flow passage into the interior of the gravel pack screen but to prevent flow of gravel packing or produced sand into the interior of the screen. The closure member may serve as a backup to a conventional one-way valve and permit additional gravel pack material to be placed in the flow passage upon completion of the gravel pack installation and in the event of early or late failure of the one-way valve.

Abstract: Methods and apparatus are described which permit stage cementing within a well bore by means of a well tool which includes a cementer having cementing ports which may be responsively opened and closed by means of a knife gate valve. The knife gate valve is disposed within the housing between outer and inner cylindrical walls and being slidable therein between an open position, wherein the cementing port is open and fluid may be communicated therethrough, and a closed position, wherein the cementing port is closed thus blocking fluid communication through said port. The knife gate valve is further operationally associated with a driver assembly and trigger device adapted to receive a trigger signal and actuate the driver assembly in response thereto. In alternate exemplary embodiments, the trigger signal may comprise an acoustical, magnetic, electromagnetic wave, electrical or other suitable signal which is received by the trigger device.

Abstract: Wellbore liners are set with a running shoe comprising a cylindrical body, end cap, check valve and receiver member in assembly. The receiver member includes threads for receiving the coupling sleeve of a running tool, and retaining wickers for engagement with a cement plug or dart to retain the same permanently engaged with and blocking the flow of fluid through the running shoe. A running tool for use with the shoe includes a coupling sleeve which is retained on a support mandrel by a collar which is secured to the mandrel with a shear pin so that pressuring up the workstring, in the event of a stuck coupling sleeve, will permit retrieval of the main part of the running tool and the workstring. The interior parts of the running shoe are made of aluminum or plastic for easy drill-out to extend the wellbore beyond the end of the liner.

Abstract: Cement plugs used in the cementing of casing in a borehole drilled into a subterranean formation are restrained from rotation by being forced into a portion of the casing and check valve apparatus which includes a reduced diameter section formed as a continuous annular liner of material having a coefficient of friction. Compression of the plug against the high-friction liner avoids rotation of the plugs when they are drilled subsequent to the cementing operation.

Abstract: To significantly reduce voids in cementing fluids and the effects of cement free fall encountered in well cementing operations, a differential pressure control regulator is inserted in series with the bottom of the well casing to be cemented. Fluid passing through the choke portion passes through an annular valve seat to one end of the tool. A valve stem is slidably and sealably mounted in the flow regulator and has a head portion which, in one position, can contact the valve seating surface and prevent any significant flow of fluid through the casing. The valve stem is biased to one position by a trap chamber filled with a fluid at a known pressure, such as atmospheric pressure, or a vacuum, so that the hydrostatic pressure existing at the bottom of the well casing normally urges the valve head into engagement with the valve seat.

Abstract: A subterranean well casing float tool has a tubular metal housing which is securable to well casing conduit. A valve is carried within the housing and comprises a frame with a valve head and seat carried relative to the frame and biased toward closed position. A compartment includes the valve head for enclosure around a bias, such as a spring, when the valve head is moved away from the valve seat. The valving components are directly secured to the housing by threads having profiled shear surfaces such that the shear area of the valving members is substantially greater than that of the housing.

Abstract: A subterranean well casing float tool is comprised of a tubular metal housing which is securable to a well casing conduit. Varing means are implaced within the housing, with substantially all of the components of the valving means, save a biasing means, are thermosetting. The valving means has a thermosetting frame and valve head and valve seat means relative to the frame. A biasing member, such as a compressed spring is used for urging the valve head toward the valve seat to a closed position. A compartment including the valve head is provided for enclosure around the biasing means when the valve head is moved fully away from the valve seat to protect the spring from errosive turbulent fluid flow when the valve head is in the open position relative to the seat. The valving means is directly secured to the housing by means of thread members having profiled shear surfaces such that the shear area of the valving means is substantially greater than that of the metal housing.

Abstract: A differential fill valve assembly for application in float collars or shoes in well casing. The valve assembly comprises a back pressure flapper valve disposed within a substantially tubular upper housing, and a lower housing containing an activating sleeve slidably disposed therein above a double flapper valve assembly. The activating sleeve initially extends into the upper housing to a sufficient extent to maintain the flapper valve in an open position and comprises a lower tubular sleeve surmounted by a circumferential ring of longitudinally upwardly extending collet fingers having radially inwardly extending shoulders thereon, said fingers and shoulders having elastomeric inserts extending therebetween; the activating sleeve is maintained in this position through use of shear pins, by which it is secured to a support ring associated with the lower housing.

Abstract: The improved poppet valve of the present invention comprises a simpler and shorter valve which meets or exceeds prior art performance characteristics while being easier and cheaper to make and to fabricate into a float collar or float shoe. The improved poppet valve of the present invention comprises a tubular one-piece body having flange means on the exterior thereof, and a downward-facing valve seat at the bottom interior thereof, with a valve guide spider thereabove. A dome-shaped poppet valve seats on the aforesaid valve seat, and has coaxially secured thereto a upwardly extending stem bolt which protrudes through and above the valve body guide spider. A spring disposed about the stem bolt biases it upwardly, acting on the top surface of the spider and on a lower surface of a spring retention cap secured to the top of the stem bolt. In such a manner, the poppet valve is biased into engagement with the valve body seat at the lower end of the valve assembly.

Abstract: An automatic fill-up floating apparatus usable in a float collar or a float shoe in a casing string. The apparatus includes a housing having a back check valve positioned therein. A spring biases the valve toward a closed position. A filling body is disposed across an opening at a lower end of the housing and includes a flow passage therethrough. The filling body is shearably pinned to a valve stem extending from the valve and has a holding position in which the valve is held in an open position. A resilient washer is annularly positioned around the valve stem and above the filling body. The washer is free to move upwardly in response to upward movement of flow through the flow passage in the filling body as the casing string is lowered into a well. The floating apparatus may be tripped by pumping fluid downwardly through the casing strings such that the washer is forced against the filling body, sealingly covering the flow passage therethrough.

Abstract: The inverse differential fill-up casing cementing float valve comprises an annular valve housing, back pressure valve assembly, a first differential pressure check valve assembly, a second differential pressure check valve assembly, and cement filler material to retain the valve assemblies within the valve housing.

Abstract: An apparatus and method for inserting flow control means into a well casing is disclosed. A receptacle having portions adapted to receive check valve means is mounted within said well casing and said well casing is inserted into a well. Check valve means may be pumped down into engagement with said receptacle to regulate the flow of fluid through the well casing. Alternatively, choke valve means may be pumped down into engagement with said receptacle instead of check valve means. The choke valve means may be constructed having portions adapted to receive check valve means so that check valve means may be pumped down into engagement with said choke valve means to regulate the flow of fluid through the well casing.

Abstract: A well casing float shoe which is adapted for a variety of well installations consists of a tubular metal shoe member filled with cementitious material having a longitudinal bore surrounding and securing in place a tubular metal sleeve. The metal sleeve is threaded at the top and bottom ends to receive a variety of sizes and types of check valves. A well casing float collar has the same construction, but the tubular shoe member is replaced with a tubular metal collar with threaded connections both above and below the cementitious filler material.

Abstract: A sub incorporating a check valve is connected into the lower end of a well pipestring. This valve will pass hot steam injected down the pipestring to the formations to loosen up the thick crude oil. The check valve prevents back flow and thus will hold the high pressure steam. To resume production, the production pump can then be lowered through the pipestring. The pump itself is provided with an extended probe member which will unseat the check valve when the pump is in proper position so that production pumping can resume.

Abstract: The invention is a differential fill valve apparatus principally for use in treating earth wells, usually in connection with cementing a string of casing into the well bore. The apparatus, at or near the low end of the casing, has a pressure actuated slidable piston which rises as liquid is encountered in the well bore opening parts for admitting liquid into the casing until the pressure from liquid in the casing reaches a predetermined ratio with respect to the pressure in the well bore annulus.Means are provided for locking the piston in its closed position after the casing string is in place in the well, permitting the use of the apparatus as conventional cementing valve apparatus.