187 results about "Snubbing" patented technology

A mobile snubbing system and method of operation transports a snubbing unit to a wellhead on a mobile platform. The snubbing unit is supported by a frame pivotable about a wellhead end of the platform for aligning the snubbing unit with the wellhead. A pipe handler boom is operable between a platform position for loading and off-loading tubulars at an open side of the platform and a second snubbing position for loading and off-loading tubulars at the top end of the snubbing unit. The boom can be telescopic for extending to the top of the snubbing unit and can be automated after learning tubular manipulation at the wellhead. Pipe racks can be deployable from the open side of the platform and an indexer and kicker in the platform enables loading and off-loading tubulars at the pipe handler.

The present invention generally relates to a snubbing or damping system for reducing a shock impact on an isolated body within a shock sensitive device, which may take the form of an inertial measurement unit (IMU). The shock sensitive device includes a housing with an inertial body suspended in an isolated manner within the housing and engaged with the snubbing system. By way of example, the inertial body may take the form of an inertial sensor assembly. Further, the snubbing system may take the form of a plastically deformable snubbing mechanism positioned between the housing and the inertial body along a line of action of the inertial body during an acceleration (e.g. shock) event.

In one aspect of the invention, an isolated power converter suitable for high power and high voltage applications comprises stacked rectifiers and lossless snubber circuits with inductors that prevent snubber diodes from delivering large current pulses into output filter capacitors when the duty cycle of the inverter is low, thereby allowing effective snubbing without unduly restricting the voltage conversion range of the power supply. In another aspect of the invention, control circuitry of a power supply comprises both a high bandwidth input current regulator and a low bandwidth output voltage regulator. The combination of a wide bandwidth input current regulator and a low bandwidth output voltage regulator allows the power supply to emulate an inductively loaded uncontrolled rectifier while restricting negative input impedance characteristics to frequencies that are substantially lower than the frequency of the ac power system.

Actuators and corresponding methods and systems for controlling such actuators offer efficient, fast, flexible control with large forces. In an exemplary embodiment, an fluid actuator includes a housing having first and second fluid ports, an actuation cylinder in the housing defining a longitudinal axis and having first and second ends in first and second directions, an actuation piston in the cylinder with first and second surfaces moveable along the longitudinal axis, a spring subsystem biasing the actuation piston to a neutral position, a first fluid space defined by the first end of the actuation cylinder and the first surface of the actuation piston, and a second fluid space defined by the second end of the actuation cylinder and the second surface of the actuation piston. A first flow mechanism controls fluid communication between the first fluid space and the first port, whereas a second flow mechanism controls fluid communication between the second fluid space and the second port. The first and second flow mechanisms are substantially restricted through two integrated snubbing mechanisms when the actuation piston approaches the first and second direction ends of its travel, respectively. In addition to a differential fluid force on the actuation piston, there is a centering or returning spring force available to help open the engine valve against the high cross-over passage pressure, without the need for the fluid actuation system to be bulky and consume too much energy.

An improved snubbing unit including a snubbing unit base, a lifting assembly having a platform positioned above the base, a rotary table positioned on the snubbing unit, and a first slip assembly positioned on the rotary table. The first slip assembly further includes a base plate with a center aperture formed therein, at least two separate slip frames positioned on the base plate around the center aperture, wherein each of the slip frames includes a slip surface, and a die carrier positioned within each of the slip frames, wherein each of the die carriers also includes a surface for engagement with the slip surfaces of said slip frames. Additionally, a second slip assembly will be positioned on the snubbing unit.

The invention relates to an overall process under-balance drilling pressure compensation system and a method for oil and gas drilling, an underground casing valve (10) is connected on a superior casing string, a wellhead rotary blowout preventer (11) is arranged at an upper end of a wellhead blowout preventer group and is connected with an under-balance throttle manifold (8) through a high-pressure hose (9), a well control manifold (12) which is connected out of a normal wellhead control device by four-pass is connected with a drilling fluid continuous pouring system in parallel by two-pass; and drilling is pulled to the front of the underground casing valve (10), the drilling fluid continuous pouring system grouts, the under-balance throttle manifold (8) controls the pressure in a shaft, and the drilling fluid which is circulated out enters a normal drilling fluid circulating system. In the drilling pulling process, the drilling fluid can be continuously poured into the shaft by a ground pressure compensation system and the bottom-hole pressure can be dynamically controlled simultaneously, thus effectively preventing formation fluid from intruding into the shaft in the drilling pulling process and keeping the steady under-balance state of the shaft.

The invention relates to a snubbing serving device of a combined type hydraulic oil-water well, which comprises a hydraulic triple ram preventer, a first annular preventer, a second annular preventer, a fixing top clamp resisting tile, a self-tightening hydraulic top clamp resisting tile, a rectangular vertical frame, two oil cylinders, a lifting cross connection, a hydraulic balanced valve, a hydraulic pressure release valve, a hydraulic equilibrium valve, a hydraulic pressure relief valve, a hydraulic source pipeline and a hydraulic source, wherein the hydraulic triple ram preventer is fixed on an oil well large cross joint, the second annular preventer is used for lifting the cross joint; the first annular preventer, the second annular preventer, the fixing top clamp resisting tile and the self-tightening hydraulic top clamp resisting tile are sequentially arranged on the hydraulic triple ram preventer, the rectangular vertical frame is erected at the periphery of the well, the two oil cylinders are symmetrically on an upright column of the rectangular vertical frame, the lifting cross connection is connected with pistons of the two oil cylinders, the self-tightening hydraulic clamp tile and the lower fixing top clamp resisting tile are arranged on the upper part of the lifting cross connection, the hydraulic balanced valve and the hydraulic pressure release valve are arranged on two through holes of both sides of the two joints of the lifting cross joint, and the hydraulic equilibrium valve and the hydraulic pressure relief valve are arranged on openings on two sides of the two connections of the lifting cross connection, the hydraulic source pipeline and the hydraulic source are matched with the snubbing serving device in an assistant mode.

A casing (31) houses therein an expansion mechanism (60) and a compression mechanism (50). The expansion mechanism (60) has a rear head (62) in which a pressure snubbing chamber (71) is provided. The pressure snubbing chamber (71) is divided by a piston (77) into an inflow/outflow chamber (72) which fluidly communicates with an inflow port (34) and a back pressure chamber (73) which fluidly communicates with the inside of the casing (31). The piston (77) is displaced in response to suction pressure variation whereby the volume of the inflow/outflow chamber (72) varies. This enables the inflow/outflow chamber (72) to directly perform supply of refrigerant to or suction of refrigerant from the inflow port (34) which is a source of pressure variation, thereby making it possible to effectively inhibit suction pressure variation.

In one embodiment, a support structure for use on a rig floor and for supporting a unit used to manipulate tubular components through a wellhead comprises a support plate adapted to securely mount the support structure to said unit, a passage in the support plate of sufficient diameter to allow tubular components to pass therethrough, a plurality of rig engaging members and at least one tensile member mount. The unit used to manipulate tubular components through a wellhead may be a compact snubbing unit or may be a push/pull unit. The support structure may further comprise a worker platform to support a worker above the rig floor. Various push/pull system embodiments, for use on a rig to manipulate tubular components through a wellhead, are also taught.

Systems and methods are provided for an underbalanced drilling (UBD) expert system that provides underbalanced drilling recommendations, such as best practices. The UBD expert system may include one or more Bayesian decision network (BDN) model that receive inputs and output recommendations based on Bayesian probability determinations. The BDN models may include: a general UBD BDN model, a flow UBD BDN model, a gaseated (i.e., aerated) UBD BDN model, a foam UBD BDN model, a gas (e.g., air or other gases) UBD BDN model, a mud cap UBD BDN model, an underbalanced liner drilling (UBLD) BDN model, an underbalanced coil tube (UBCT) BDN model, and a snubbing and stripping BDN model.

The invention relates to a downhole gel slug and a preparation method thereof, which is characterized in that it consists of a monomer, a crosslinking agent, an initiator, a density modifier, a viscosity modifier and water; wherein the weight percentage of each component is: Monomer: 4.5-9%; Cross-linking agent: 0.1-0.14%; Initiator: 0.005-0.06%; Density modifier: 5-10%; Viscosity modifier: 0.1-1.0%; Ratio, dissolve the monomer and cross-linking agent in water, then add the viscosity modifier and stir to disperse evenly, then add the density modifier and stir to disperse evenly, and finally add the initiator before injection, and make the gel slug base after mixing evenly The gel slug base fluid is injected into the predetermined position of the wellbore to form the gel slug. The gel slug of the present invention can safely and effectively seal the wellbore downhole, realize snubbing tripping, and has the characteristics of high strength, good temperature resistance, simple preparation method and good economic benefit.

An hydraulic snubbing unit has a pair of hydraulic cylinders for moving travelling snubbing slips towards and away from stationary snubbing slips to snub a pipe through the snubbing unit, the hydraulic cylinders having spaced, parallel cylinder rods. A pipe guidance apparatus has pipe guides between the stationary snubbing slips and the travelling snubbing slips, the pipe guides each having a pair of cylinder rod openings spaced apart from one another and slidably receiving the rods of the hydraulic cylinders and a pipe guidance opening located between the cylinder rod openings and slidably guiding the pipe, and a pipe guide spacer having extendable and contractible interconnections between the pipe guides. In a contracted condition of the pipe guide spacer, the interconnections are contracted and the pipe guides are moved into proximity to one another by the simultaneous movement of the cylinder rods slips towards the stationary slips, and in an expanded condition, the interconnections are extended and the pipe guides are moved apart from one another by the simultaneous movement of the cylinder rods away from the stationary slips to provide lateral support of the pipe at intervals along the pipe.

A system and method for monitoring and controlling a snubbing unit having traveling slips and stationary slips are provided. Position sensors are associated with the slips for directly or indirectly detecting opened and closed positions of the slips, including detecting a rotational position of a crankshaft that drives the slips into engagement with a pipe. Load sensors are associated with the slips for detecting load status of the slips. A control system receives input signals from the sensors, and confirms that either the traveling slips or the stationary slips are loaded before releasing or allowing the release the opposing set of slips, when transferring the pipe string load from the one set of slips to the other set of slips.

The present invention is to provide an electro hydrostatic actuator excellent in a snubbing characteristic including a cylinder type actuator main body 1, a piston 2 having a piston rod, the piston slidingly moving in a cylinder of the actuator main body, a motor 18, a pump 19 for supplying fluid according to the rotation of the motor, a mechanism for adjusting a running amount of the fluid into and from the cylinder according to the motion of the piston, and a reservoir 8 for adjusting the supply of the fluid corresponding to a volume difference generated according to the motion of the piston, and a controller 17 which controls the number of revolutions of the motor according to the calculated load torque, and a snubbing control method used for this. An electro hydrostatic actuator of realizing a snubbing mechanism capable of increasing energy efficiency, when used for a landing gear retraction/extension device of an airplane, can be provided.

A hydraulic cylinder has a tube with a first end and a section end. The hydraulic cylinder also has a piston assembly movably disposed within the tube and configured to move between the first and second ends of the tube. The hydraulic cylinder further has a valve plunger connected to the piston assembly and having an axial bore. The hydraulic cylinder additionally has a cap assembly connected to the tube to close off the first end of the tube. The cap assembly has a fluid passageway and the valve plunger is configured to progressively restrict fluid flow through the fluid passageway as the piston assembly approaches the first end of the tube.

A pipe guide apparatus for guiding a pipe during snubbing of the pipe includes a pair of hydraulic cylinders and cylinder rods; a stationary guide affixed between a bottom jack plate and a top jack plate, comprising a stationary pipe guide; a travelling jack plate affixed to the cylinder rods; a travelling pipe guide in sliding engagement with the cylinder rods and connected to the travelling jack plate by a lift rod. The stationary pipe guide and the travelling pipe guide each define a pipe opening and has a flexibly resilient guide member having an opening with a diameter closely matching the outside diameter of the pipe being snubbed.

A landing gear system for an aircraft includes a retractable landing gear assembly, a hydraulic actuator for actuating movement part, for example a bogie of the landing gear assembly, and an accumulator associated with the actuator. The accumulator comprises a volume of pressurised gas separated from hydraulic fluid by a separator piston. Travel of the separator piston beyond a certain position is indicative of a fault. The accumulator includes a snubbing device that acts to slow movement of the separator piston beyond that position. A monitoring system measures the time taken for the movement of the landing gear part effected by the hydraulic actuator. If the measured time is longer than a threshold time, that is indicative of a possible fault in the accumulator, that might, without the snubbing, remain undetected and/or hidden from view.

System and method for controlling current across a load. A preferred embodiment comprises a current varying circuit (such as current varying circuit 525) that can create a sequence of voltage drops in a driver circuit (such as the driver circuit 505) coupled to an inductive load (such as the inductive load 535). By initially producing a large voltage drop and then stepping the voltage drop down gradually, the current in the inductive load can be rapidly removed without producing a current undershoot, which, in certain applications, can result in unwanted noise and vibration.