Apparatus for tubular drill string making or breaking
An apparatus for tubular drill string making or breaking including top wrench assembly, bottom wrench assembly, support structure, and control device. The top wrench assembly includes two top wrench bracket assemblies, top pair of movable gripping arms, top arm actuator, and top wrench camming actuator. The arm actuator allows the gripping arms to be closed or opened around the outer circumference of the pipe section, allowing top wrench assembly to engage differing casing sizes. The bottom wrench assembly includes two bottom wrench bracket assemblies, bottom pair of movable gripping arms, and bottom arm actuator. The bottom arm actuator allows the gripping arms to be closed or opened. The top wrench assembly is directly mounted on top of the bottom wrench assembly to allow relative rotation of the drill pipe section therewith. Once a pair of rollers is rotated by a hydraulic motor in the top wrench, or a pair of stationary rollers in the bottom wrench are both engaging with outer surface of the drilling string, the rollers automatically and naturally centralize or align a die insert to the most desirable central position. At this point the maximum number of die insert teeth evenly bite into the outer surface of the drill string.
The invention is an automated apparatus having a wrenching device integrated with a rotating device. The apparatus is used here for making and breaking tubular drill string.
SUMMARY AND ADVANTAGES OF THE INVENTIONThis invention includes three major components of a top wrench, a bottom wrench, and a support structure. The top wrench can advantageously rotate clockwise or counter clockwise about the centerline of the drill string while being supported on the bottom wrench by a hydraulic actuator.
The top wrench has a clamping wrench assembly and a rotating assembly integrated into a single unit through a common structural frame or bracket. The top wrench assembly includes a wrench clamping actuator, a die insert holder and die insert, mounted at a geometrically symmetrical center between a pair of rotatable rollers through a common structural frame or bracket. The integrated top unit is pivotally mounted to the front end of an arm which is also pivotally mounted at the rear end of the arm. The top pair of arms carrying the unit can open or close at the front end while pivoting about the rear end through a hydraulic cylinder connecting both arms to engage the surface of a pipe section.
The bottom wrench has a clamping wrench assembly and a pair of stationary rollers integrated into a single unit through a common structural frame or bracket. The bottom clamping wrench assembly includes a wrench clamping actuator, a die insert holder and die insert, mounted at a geometrically symmetrical center between the pair of stationary rollers through a common structural frame or bracket. The integrated bottom unit is pivotally mounted to the front end of an arm which is also pivotally. The bottom pair of arms can open or close at the front end while pivoting about the rear end through a hydraulic cylinder connecting both arms through a pin to engage the outer surface of the drill pipe section.
Advantageously, once the pair of rollers is rotated by a hydraulic motor in the top wrench, or the pair of stationary rollers in the bottom wrench are both engaging with outer surface of the drilling string, the rollers automatically and naturally centralize or align the die insert to the most desirable central position. At this point the maximum number of die insert's teeth evenly bite into the outer surface of the drill string. This is desirable for producing an optimum and maximum making or breaking torque once the wrench clamping actuator pushes the die holder out to position the die insert against the pipe section.
The apparatus according to the invention permits usage with a range of pipe sized without having to change parts.
The preferred exemplary embodiments of the present invention are described in further detail below in conjunction with the accompanying drawings. In which:
Referring now to
The top wrench assembly 10 is described in greater detail with reference now to
The bottom wrench assembly 20 is described in greater detail with reference now to
The bottom arm actuator 26 is pivotably linked to each arm 24 by arm actuator pivot pins 27. The arm actuator 26 allows the gripping arms 24 to be closed or opened around the outer circumference of the pipe section 2, in order for the bottom wrench assembly 20 to engage differing casing sizes. The arm actuator 26 is preferably a hydraulic cylinder of a known type recognized in the field, therefore detailed explanation of such an actuator is unnecessary, although it will be understood other types of linear actuator may be employed.
Referring now to
The top wrench bracket assembly 12 is shown in greater detail in
The bottom wrench bracket assembly 22 is shown in greater detail in
The assembled apparatus as seen in
The top wrench assembly 10 sits on the bottom wrench assembly 20 and can be rotated freely about the center of the string 2 by the actuator 18 which is attached to the back end of the top wrench assembly 10 at one side thereof and to the support structure 30 on the end 32 thereof. The cam 72 and the cam follower 74 guide the rotation and provide additional support for the top wrench assembly rotation on top of the bottom wrench assembly. The top wrench assembly 10 is also guided by a cam follower which may be embodied as in the preferred embodiment by a pair 74 of cam followers mounted on the top wrench 10 and engaged with the cam 72. The cam 72 attached to the support frame has the same diametric center as the pipe section or string 2 so that once the top wrench assembly 10 rotates thereabout the cam follower 74 rotate about the center of the string within the cam 72.
It will be understood that the control device 40 provided is capable of controlling all of the motors, actuators, etc., associated with the apparatus 1 described herein.
The foregoing relates to the preferred exemplary embodiment of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.
Claims
1. An apparatus for making or breaking a tubular drill string, having a wrenching mechanism integrated with a rotating mechanism, comprising:
- a first wrench assembly (10) including
- a first bracket means (12) for carrying a die insert (54);
- actuating means (57) for actuating the die insert (54) within the first bracket means (12) to position the die insert relative to a pipe section (2) during a drill string making process; and
- a pair of rotatably driven rollers (55) mounted rotatably on the first bracket means (12), wherein the die insert (54) is disposed on the bracket means (12) at a symmetrical center between the pair of rotatably driven rollers (55).
2. The apparatus according to claim 1, wherein the first wrench assembly (10) further includes a pair of movable gripping arms (14) pivotally connected together, wherein a first bracket means (12) is pivotably mounted to each of the movable gripping arms (14).
3. The apparatus according to claim 2, further comprising a camming means (18, 50) for rotating the first wrench assembly (10) relative to a support member around a centerline of a pipe section 2 during a drill string making process.
4. The apparatus according to claim 1, further comprising a second wrench assembly (20) including
- a second bracket means (22) for carrying a die insert (64);
- actuating means (67) for actuating the die insert (64) within the second bracket means (22) to position the die insert relative to a pipe section (2) during a drill string breaking process; and
- a pair of rotatably fixed rollers (65) fixedly mounted on the second bracket means (22), wherein the die insert (64) is disposed on the second bracket means (22) at a symmetrical center between the pair of rotatably fixed rollers (55).
5. The apparatus according to claim 4, wherein the second wrench assembly (20) further includes a pair of movable gripping arms (24) pivotally connected together, wherein a second bracket means (22) is pivotably mounted to each of the movable gripping arms (24) of the second wrench assembly (20).
6. The apparatus according to claim 6, wherein the second wrench assembly (20) embodies the support member.
Type: Application
Filed: Apr 11, 2008
Publication Date: Oct 15, 2009
Inventor: Yaogen Ge (Katy, TX)
Application Number: 12/081,151
International Classification: E21B 19/18 (20060101);