Patent Application
20190316429
Embodiments disclosed herein relate to a wrench tool for coupling or de-coupling tubulars utilized in the oil and gas industry. The wrench tool has a circuit that makes a grip force applied by the wrench tool proportional to a torque force applied by the wrench tool.
A spinner and wrench tool (also known as a “spinner and tong”) is commonly used in the oil and gas industry to rotate a tubular when making up or breaking out a threaded connection. The spinner and wrench tool rotates a tubular relative to another tubular to thread the tubulars together during a make-up operation, and rotates the tubular in an opposite direction to unthread the tubulars from each other during a break-out operation. The spinner is a relatively low torque, high speed device used for the initial makeup of a threaded connection. The wrench is a relatively high torque, low speed device that is coupled to the spinner and subsequently used to provide a greater amount of torque to complete the threaded connection.
The wrench (also known as a “power tong”) may be composed of upper and lower torque bodies having a plurality of grippers that are moved into contact with the tubulars. The upper torque body is configured to rotate one of the tubulars relative to the other tubular, which is held stationary by the lower torque body, to couple or decouple the tubulars. One problem that often occurs is that the grippers grip one of the tubulars with an amount of force that tends to distort the circular shape of the tubular into an oval shape. The distortion of one of the tubular creates an amount of friction between the tubulars when coupling the tubulars together that detrimentally impacts the threaded connection. For example, the amount of friction between a box end and pin end during a make-up operation often results in a misapplication of the appropriate amount of torque required to make up the threaded connection, resulting in an incomplete threaded connection that can leak.
Therefore, there exists a need for new and/or improved wrench tools.
In one embodiment, a wrench assembly comprising a lower clamp assembly having a plurality of first grip assemblies; an upper clamp assembly coupled to the lower clamp assembly, the upper clamp assembly having a plurality of second grip assemblies and a plurality of torqueing cylinders coupled thereto; and a hydraulic circuit in fluid communication with the torqueing cylinders and each of the first and second grip assemblies, wherein the hydraulic circuit is configured to control a gripping force applied by the first and second grip assemblies relative to a torqueing force applied by the torqueing cylinders such that the gripping force is proportional to the torqueing force.
To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one embodiment may be beneficially utilized with other embodiments without specific recitation.
Embodiments of the disclosure include a wrench tool for making up and breaking out a threaded connection between two tubulars. The wrench tool may be used with a spinner tool. The spinner tool is a relatively low torque, high speed device used for the initial makeup of the threaded connection. The wrench tool is a relatively high torque, low speed device that is coupled to the spinner tool and is subsequently used to provide a greater amount of torque to complete the threaded connection.
The wrench tool includes an upper clamp assembly and a lower clamp assembly. During a make-up or break-out operation, the upper clamp assembly grips and rotates one tubular, while another tubular is gripped and held stationary by the lower clamp assembly. The upper and lower clamp assemblies include independently operated grippers that grip an outer diameter of the respective tubulars. The wrench tool is used to apply a specified torque value to the threaded connection between the two tubulars.
The wrench tool as described herein includes a proportional grip circuit that limits the amount of force applied by the grippers of the lower clamp assembly to one tubular based on the amount of torque applied by the grippers of the upper clamp assembly to another tubular. The lower clamp assembly grips and holds a box end of one tubular in a stationary position, while the upper clamp assembly grips and rotates a pin end of another tubular relative to the box end to thread the tubulars together.
The wrench assembly 105 includes an upper clamp assembly 115 and a lower clamp assembly 120. The wrench assembly 105 also includes torqueing cylinders 112 that rotate the upper clamp assembly 115 relative to the lower clamp assembly 120 about a tool axis TA. The upper clamp assembly 115 and the lower clamp assembly 120 include a plurality of grip assemblies 125 and 130, respectively. Although only one grip assembly 125, 130 for each clamp assembly 115, 120 is shown, the upper and lower clamp assemblies 115, 120 can have two, three, four, or more grip assemblies 125, 130 that are equally spaced apart from each other.
The upper grip assembly 125 includes one or more upper grip actuators 135. The lower grip assembly 130 includes one or more lower grip actuators 140. The grip assemblies 130 of the lower clamp assembly 120 may be used to grip a box end of a first tubular. The grip assemblies 125 of the upper clamp assembly 115 may be used to grip a pin end of a second tubular.
In a make-up operation, the wrench tool 100 is brought into proximity with a first tubular, which may be held by a rotary spider on a rig floor for example. The grip assemblies 130 of the lower clamp assembly 120 are actuated by the lower grip actuators 140 to grip the box end of the first tubular. A pin end of a second tubular is positioned on top of the box end of the first tubular, which may be lowered by an elevator or top drive for example.
The second tubular is rotated by a spinner tool (not shown) to initially make up the threaded connection between the first and second tubulars. After the initial make up, the grip assemblies 125 of the upper clamp assembly 115 are actuated by the upper grip actuators 135 to grip the pin end of the second tubular, while the box end of the first tubular remains gripped by the lower clamp assembly 120. The upper clamp assembly 115 then is rotated by the torqueing cylinders 112 relative to the lower clamp assembly 120 to further tighten and complete the thread connection between the first and second tubulars.
To prevent the application of an excessive amount of grip force by the grip assemblies 130 of the lower clamp assembly 120, the wrench tool 100 includes a proportional grip circuit 150 that controls the amount of fluid, which dictates the pressure supplied to the lower grip actuators 140 that actuate the grip assemblies 130. The proportional grip circuit 150 is in fluid communication with a pump 155, which supplies pressurized fluid to the wrench tool 100, and specifically controls the amount of pressurized fluid supplied to the torqueing cylinders 112, the lower grip actuators 140, and the upper grip actuators 135 as further described below.
The torqueing cylinders 112 are in fluid communication with the proportional grip circuit 150 by fluid lines 160, 165 (which may be conduits or hoses for example) that control torque application by moving the upper clamp assembly 115 relative to the lower clamp assembly 120 in the direction of reference arrow TD (shown in
The lower grip actuators 140 are in fluid communication with the proportional grip circuit 150 by fluid lines 180, 185 (which may be conduits or hoses for example) that control extension and retraction of the grip assemblies 130. The proportional grip circuit 150 controls the amount and direction of pressurized fluid supplied through the fluid lines 180, 185 to the grip actuators 140 to actuate the grip assemblies 130.
The upper grip actuators 135 are in fluid communication with the proportional grip circuit 150 by fluid lines 170, 175 (which may be conduits or hoses) that control extension and retraction of the grip assemblies 125. The proportional grip circuit 150 controls the amount and direction of pressurized fluid supplied through the fluid lines 170, 175 to the grip actuators 135 to actuate the grip assemblies 125.
While the proportional grip circuit 150 is shown and described in
A second grip controller 210, which controls actuation of the lower clamp assembly 120, is in fluid communication with the pump 155 via a valve 225 and fluid lines 157, 226, 227. The valve 225 may be a pressure control valve, such as a remote compensator valve. Fluid from the pump 155 flows through fluid line 157, through valve 225, through fluid 226, and through the second grip controller 210 to supply fluid to fluid lines 180, which force the grip assemblies 130 into a retracted position such that the lower clamp assembly 125 is not gripping the box end 200B of the second tubular. Fluid in the grip assemblies 130 may be returned to a reservoir 228 via fluid lines 185 through the second grip controller 210.
A torque controller 215, which control actuation of the torqueing cylinders 112, is in fluid communication with the pump 155 via a valve 250 and fluid lines 158, 251, 252. As shown, the torque controller 215 is in a neutral position such that no fluid from the pump 155 is flowing to the torqueing cylinders 112 via fluid lines 251, 252. The torqueing cylinders 112 are not applying any torque to the upper clamp assembly 115.
The first and second grip controllers 205, 210, when actuated, also place fluid line 222 in fluid communication with fluid line 224, and fluid line 227 in fluid communication with fluid line 229, respectively. Fluid in fluid lines 224 and 229 flows to a first check valve 230, which directs the fluid to a first relief valve 240 via fluid line 231. The check valve 230 may be a back-to-back check valve.
When pressure in the fluid line 231 exceeds a predetermined amount, the relief valve 240 opens and the fluid is dumped into a reservoir 236 via fluid line 234. The fluid can also flow into the reservoir 236 via fluid line 234 by first flowing through fluid lines 232 and 233 and a control valve 235 (as further described below). The relief valve 240 may be preset, adjusted manually, or controlled remotely to set the amount at which the relief valve 240 opens. In this manner, the relief valve 240 helps control the amount of gripping force that can be applied by the upper and lower clamp assemblies 115 and 120 to the pin end 200A and the box end 200B of the first and second tubulars, respectively.
The control valve 235, which may be a directional control valve, is an optional component of the proportional grip circuit 150 and also helps control the amount of gripping force that can be applied by the upper and lower clamp assemblies 115 and 120. The control valve 235 is biased into an open position (as shown in
When the control valve 235 is closed, fluid in the line 232 is directed through a second check valve 246 to a fluid line 248 and to a second relief valve 245, which is set to open when pressure in the fluid line 248 exceeds a predetermined amount. The amount of pressure needed to open the relief valve 245 adds to the amount of pressure need to open the relief valve 240 when the control valve 235 is closed. Specifically, the fluid pressure in the fluid line 232 increases the pressure setting of the relief valve 240. The maximum amount of gripping force applied by the upper and lower clamp assemblies 115, 120 is therefore increased.
For example, if the relief valve 240 is set to open at about 500 psi, and the relief valve 245 is set to open at about 1000 psi, then the maximum amount of gripping force applied by the upper and lower grip assemblies 125 and 130 would be 1,500 psi. The relief valve 245 may be preset, adjusted manually, or controlled remotely to set the predetermined amount at which the relief valve 245 opens. In this manner, the gripping force applied by the upper and lower clamp assemblies 115, 120 can also be adjusted by adjusting the amount of pressure needed to open the relief valve 245.
The torque controller 215, when actuated into the torqueing position, also places fluid line 252 in fluid communication with fluid line 247. Fluid in fluid line 247 flows to the check valve 246, which directs the fluid to the relief valve 245 via fluid line 248. The check valve 246 may be a back-to-back check valve. The relief valve 245 may be a direct acting relief valve. Fluid flowing through the relief valve 245 flows into fluid line 234 and then to the reservoir 236. The relief valve 245 can be adjusted to control the amount of torque that is applied by the torqueing cylinders 112 to the upper clamp assembly 115. For example, if the relief valve 245 is configured to open when fluid in the fluid line 248 exceeds 500 psi, then the maximum amount of torque that the upper clamp assembly 115 can apply would be 500 psi since any pressurized fluid in excess of 500 psi would be relieved to the reservoir 236.
The torqueing force applied by the torqueing cylinders 112 is controlled solely by the relief valve 245. The gripping force applied by the upper and lower grip assemblies 125 and 130 is controlled solely by the relief valve 240 when the control valve 235 is in the open position. The gripping force applied by the upper and lower grip assemblies 125 and 130 is controlled by the combination of the relief valve 245 and the relief valve 240 when the control valve 235 is in the closed position.
When the proportional grip circuit 150 is in the gripping and torqueing mode as shown in
While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure thus may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
