摘要:
A self-retaining cementing wiper plug has two or more steel or carbide tipped holddown fingers or slips extending radially outward from the plug for engaging the inner surface of the casing and preventing the plug from moving uphole over time and potentially interfering with other downhole apparatus such as a pump.
摘要:
A stabilizer is provided for stabilizing a rotary or progressive cavity pump suspended from production tubing in well casing. The stabilizer is connected between the production tubing and the pump. The stabilizer has a tubular body having a cylindrical wall and a longitudinal bore contiguous with the production tubing. A releasable sliding dog is disposed on the exterior of the tubular body and is operatively connected by a link to one or more pistons. Each piston is disposed in a piston housing that is in fluid communication with the bore of the tubular body. Circumferentially spaced-apart feet extend radially outwardly from the tubular body. In operation, actuating fluid pressure advances the pistons uphole, driving the sliding dog up one or more longitudinal outwardly extending ramps to brace against the casing, with the feet contacting the casing and bearing opposing reactive force. Preferably, the sliding dog and the feet form a three-point contact with the casing that arrests lateral movement in any direction. Under non-actuating pressure, upward drag on the sliding dog compresses the pistons, retracting the dog, and permitting removal of the stabilizer and pump.
摘要:
A progressive cavity pump pumps liquid downhole to a lower formation past a packer set in a casing of a wellbore. The rotor of the pump is axially restrained by a bearing assembly spaced below the pump for controlling uphole reactive loading on the rotor. Preferably the rotor is releasably coupled to the bearing assembly for release and recovery of the rotor from the bearing assembly. Such a releasable coupling is a latch comprising a plunger telescopically and releasably coupled with a housing using a dog and track arrangement, the dog and track utilizing the telescoping action to actuate the coupling and releasing of the latch.
摘要:
A self-aligning stuffing box having a spherical joint between the upper and lower portions of the housing permits universal movement of the upper portion relative to the lower portion to permit a rod to pass through the bore if the axis of the rod is misaligned relative to the axis of the bore in each of the upper and lower housing portions. An energized seal in the upper housing resides at or below the spherical joint due to a downwardly depending central portion of the upper housing which extends into a recess formed in the lower housing permitting the height of the stuffing box to be relatively short. A second seal is positioned above the first seal and may be spaced sufficiently above the first seal to permit a flapper valve to be installed between the seals. The flapper valve is mounted through a port in the upper housing which is accessible without disassembly of the stuffing box, the seals or the wellhead.
摘要:
A progressive cavity pump pumps liquid downhole to a lower formation past a packer set in a casing of a wellbore. The rotor of the pump is axially restrained by a bearing assembly spaced below the pump for controlling uphole reactive loading on the rotor. Preferably the rotor is releasably coupled to the bearing assembly for release and recovery of the rotor from the bearing assembly. Such a releasable coupling is a latch comprising a plunger telescopically and releasably coupled with a housing using a dog and track arrangement, the dog and track utilizing the telescoping action to actuate the coupling and releasing of the latch.
摘要:
A tool is provided for preventing the rotation of a downhole tool or rotary pump stator, the tool comprising a tubular housing and a jaw which is biased radially outwardly from the tool to engage the casing wall for arresting tool rotation and providing significant stabilization of a rotary pump. In doing so, the tool housing moves oppositely to rest against the casing opposite the jaw. The tool housing and the downhole tool are thereby restrained and stabilized by the casing wall. The tool's jaw is released by opposite tool rotation. Preferably, the jaw is biased outwardly from the tool housing to a casing-engaging position by a torsional member, housed along the axis of the hinge of the jaw. The tool is released from the casing by opposite tool rotation which increasingly compresses the jaw toward the housing, twisting the torsional member into torsion, which then acts to urge the jaw outwardly again. Overextension of the jaw during assembly is prevented using cooperating stops in the jaw and the housing.
摘要:
An axial flux switched reluctance motor utilizes one or more rotor discs spaced along a rotor shaft, each rotor disc having a plurality of rotor poles spaced along the periphery thereof. Stator elements are distributed circumferentially about the rotor discs and form pairs of radially extending stator poles for axially straddling the rotor discs. Stator coils as switched on to energize pairs of stator poles for forming an axial and radially inward flux path for rotating the rotor poles for minimizing the flux path before switching off the stator coil. Two or more rotor discs can be rotationally indexed for providing two or more motor phases. In manufacture, rotor discs and circumferentially extending stator coils about the periphery of each rotor disc are fit to a stator housing. Each stator element is then fit radially through the stator housing and secured thereto for straddling the rotor discs.
摘要:
A self-retaining cementing wiper plug with a packer element has two or more steel or carbide tipped holddown fingers or slips extending radially outward from the plug for engaging the inner surface of the casing and preventing the plug from moving uphole over time and potentially interfering with other downhole apparatus such as a pump. The packer element in the wiper plug is actuated when the plug is supported by an obstruction under the plug and then compressed, the packer being maintained in compression by the holddown fingers.
摘要:
A tool is provided for preventing the rotation of a downhole tool or rotary pump stator, the tool comprising a tubular housing and a jaw which is biased radially outwardly from the tool to engage the casing wall for arresting tool rotation and providing significant stabilization of a rotary pump. In doing so, the tool housing moves oppositely to rest against the casing opposite the jaw. The tool housing and the downhole tool are thereby restrained and stabilized by the casing wall. The tool's jaw is released by opposite tool rotation. Preferably, the jaw is biased outwardly from the tool housing to a casing-engaging position by a torsional member, housed along the axis of the hinge of the jaw. The tool is released from the casing by opposite tool rotation which increasingly compresses the jaw toward the housing, twisting the torsional member into torsion, which then acts to urge the jaw outwardly again.
摘要:
A frameless switched reluctance motor (SRM) has a stator sandwiched between two housings. Axial load on the rotor shaft is directed through a first bearing, through the first housing to the stator and through the second housing to a motor support. Heat is dissipated using low-loss electrical steel, one or more air movers and air passages through the motor. Preferably a stator profile enables the air passages to be formed through the stator's lamination stack. Optionally air is routed through passages between the coils and through air passages along the air gap and radially through passages between an upper and a lower stator. A first self aligning bearing adapts to misalignment between the first housing and the shaft and a second bearing is provided with transverse movement. Preferably, the frameless motor is adapted for support to a wellhead for driving a downhole rotary pump and a rotary rod string.