Apparatus and method for installing a sucker rod guide

A fluid powered tool is disclosed for assembling a two piece guide on a sucker rod at a well site. The tool includes a table (26) laterally moveable with respect to the sucker rod and supporting a fluid powered cylinder (28), a bottom plate (42) for engaging the rod guide, and a top plate (56) also for engaging the rod guide. At least one vertical guide (30) is provided for guiding vertical movement of at least one of the bottom plate and top plate, and a horizontal rail (32) is provided for guiding lateral movement of the table. Each of the top plate and the bottom plate include a recess for receiving the sucker rod when engaged by the guide. The fluid powered cylinder moves the bottom plate with respect to the top plate to assembly the guide on the rod.

FIELD OF THE INVENTION

The present invention relates to tools and equipment for installing a guide on a sucker rod. More particularly, the invention relates to a powered tool for axially moving a first rod guide component relative to a second rod guide component to assemble the guide on a sucker rod.

BACKGROUND OF THE INVENTION

Sucker rods are commonly used in oilfield operations to power a downhole pump in a well, thereby pumping downhole fluids to the surface. The pumped fluids may be oil or other hydrocarbons, or may be water which is removed from the well so that gas production may be increased. Sucker rods of this type may be reciprocated to power the downhole pump or alternatively may be rotated. In either event, rod guides have conventionally been used on sucker rods to minimize wear on the tubing string by preventing the sucker rod from contacting the tubing string, thereby enhancing the useful life of the well.

Various types of rod guides have been devised, and various types of tools have been used for installing guides on sucker rods. Many rod guides are of the type which have a substantially unitary body with a C-shaped cross-sectional configuration, so that a slot in the guide is spread apart to laterally position the guide on the sucker rod. A sucker rod guide installation device for a single piece sucker rod guide is disclosed in U.S. 2006/0137885A1. Two piece rod guides of the type disclosed in U.S. Pat. No. 5,358,041 have been assembled on a sucker rod utilizing an operator powered lever tool. The time and difficulty associated with assembling a guide by this technique can be a significant deterrent to use of such a guide.

The disadvantages of the prior art are overcome by the present invention, and an improved method and apparatus for installing a two-piece guide on a sucker rod are hereinafter disclosed.

SUMMARY OF THE INVENTION

In one embodiment of the invention, a fluid powered tool for assembling a two piece guide on a sucker rod at a well site comprises a table laterally movable with respect to the sucker rod, with the table supporting a fluid powered cylinder, a bottom plate for engaging the rod guide, a top plate for engaging the rod guide, and a vertical rail for guiding the vertical movement of one or more of the bottom plate and the top plate. The tool further includes at least one horizontal rail for guiding lateral movement of the table. Each of the top plate and the bottom plate containing a recess for receiving the sucker rod when the guide engages the respective plate. The fluid powered cylinder moves the bottom plate with respect to the top plate to assemble the guide on the rod.

According to one embodiment of the method of the invention, the two piece rod guide is assembled on a sucker rod by supporting a fluid powered cylinder, a bottom plate, a top plate, and one or more vertical guides on a table. The table is guided for lateral movement by one or more horizontal rails. A recess is formed in each of the bottom plate and the top plate for receiving the sucker rod when the guide engages a respective plate. A bottom plate is moved axially with respect to the top plate to assembly the guide on the sucker rod.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1illustrates a hydraulic installation tool10according to the present invention for assembling a two-piece rod guide on a sucker rod at a well site. The installation tool comprises a frame12with a screen14extending between vertical frame components. A top plate16and a bottom plate18are each provided with a opening20for receiving a sucker rod therein.FIG. 1also depicts a lever22which is manually operable between a first position as shown inFIG. 1to an intermediate or second position, and to a third or active position. A lower threaded nipple24is shown inFIG. 2for threading the assembly to the top of a wellhead or other suitable structure.

Referring toFIG. 2, the assembly includes a laterally movable table26including hydraulic cylinder28and vertical support30. More particularly, the table is laterally movable along the horizontal axis of rail32, with a pair of bearing members34desirably providing a guiding function for easily moving the table laterally (horizontally) by moving the lever arm22. Preferably a pair of spaced apart rails are provided for this purpose, with each rail having a pair of bearing members.FIG. 2also illustrates a portion of a sucker rod36with rod guide components38and40partially assembled and positioned on the rod36. As more fully disclosed below, the installation tool10acts to axially move the components38and40together, so that the rod guide is fully assembled on the rod36while the rod extends down into the well.

InFIG. 3, the lever or handle22has been activated to move the table and thus the cylinder28and the vertical guide30to an intermediate position closer to the rod string36. InFIG. 4, the rod string is then lowered until component40of the rod guide engages the top of tag plate42of the table, which is supported on a connecting plate44between the cylinder28and the vertical guide. Engagement of the guide with the tag plate42when in the intermediate position is shown inFIG. 11. InFIG. 5, the lever22is again activated until the table is moved to the third or activated position. In this position, the lower component40of the rod guide engages the surface of a frustoconical opening52in the bottom plate42, as shown inFIG. 12, thereby maintaining the lower portion of the rod guide centered with respect to the axis of the rod. As shown inFIG. 6, the cylinder28may then be activated to raise the tag plate42, thereby moving the lower half40of the rod guide axially into engagement with the upper half38of the rod guide. As the lower portion40of the guide moves upward, the upper portion38of the guide is prevented from continuing to move upward since the upper portion of the guide engages the frustoconical opening54in the upper plate56, as shown inFIG. 13. Upward movement of the tag plate42in response to activation of the cylinder28thus moves the lower portion of the rod guide axially upward until the rod guide is fully assembled on the rod.FIG. 7depicts the cylinder28opened with the rod guide fully assembled on the sucker rod36.

To finish the installation, the rod string may be slightly lowered, as shown inFIG. 8, so that it will not interfere with movement of the table26, and the table may then be moved back to the first or default position, as shown inFIG. 9. InFIG. 10, the rod string is lowered downhole past the installation device10. The process may then be repeated for each rod guide assembled on the string.

FIG. 11illustrates a top view of the installation tool, with the top plate16and the upper plate56of the table removed for clarity of the tag plate or bottom plate42.FIGS. 11,12, and13also depict the pair of spaced apart rails32and the bearing members discussed above. It should be understood that in a preferred embodiment, the frame60of the insulation tool may remain substantially stationary with respect to the rod string, and the components supported on the table move laterally between the first, second, and third positions. Thus it should be understood that when the table is in the first or inactive position, the frame60will be generally positioned as shown onFIG. 11with respect to the sucker rod, but the component supported on the rails32will be to the right of the intermediate position shown inFIG. 11. In this intermediate position, it should be understood that the lower portion of the rod guide will thus engage the tag or bottom plate42, thereby serving as a stop to prevent further downward movement of the rod guide with the string. In the third or active position, as shown inFIG. 12, the table and its supported components have been moved to the left from the position as shown inFIG. 11, so that the rod and the rod guide are thus now positioned within the frustoconical opening52in the plate42, thereby serving to maintain the lower portion of the rod guide centered with respect to the rod when the cylinder28is activated to move the lower plate upward and thus assemble the guide on the sucker rod.

FIG. 13is a simplified pictorial view of the rod guide assembly with some components removed for clarity. Most importantly,FIG. 13illustrates the frustoconical surface54in the upper plate56, so that the upper portion38of the rod guide engages this frustoconical surface on the upper plate56to stop upward movement of the rod guide as the cylinder28is activated to move the lower portion of the rod guide upward and assemble the guide on the rod.

In a preferred embodiment, a plurality of spaced apart horizontal guide rails30are provided for guiding movement of the lower plate in response to activation of the cylinder28as it moves upward. In a preferred embodiment, four vertical guide rails are attached to the connecting plate26, and serve to guide movement of the tag plate42as it moves upward in response to activation of the cylinder28.

The installation tool as described herein presents a significant advancement over manually operated tools, both in terms of the time required to install a guide on a sucker rod, and the risks associated with that installation.

A hydraulically powered tool is preferred for many applications, but a pneumatically powered tool could be used for some applications. A fluid powered tool is preferred over an electrically powered tool for many applications due to the explosive hazards associated within the well. Also, the tool is preferably arranged so that the cylinder28is retracted to assemble the guide on the rod, but in other embodiments the cylinder could be normally retracted and then extended to assemble the guide on the rod. The latter alternative may require more vertical space for the installation tool, which is generally undesirable.

In a preferred embodiment, the horizontal rail for guiding lateral movement of the table comprises a first rail and a second rail, with the rails being spaced apart for guiding lateral movement of the table between the first, second and third positions. Also, a vertical guide for guiding vertical movement of the bottom plate preferably comprises a plurality of spaced apart vertical rails, so that the bottom plate moves uniformly upward as it is guided by the plurality of vertical rails when the cylinder is activated.FIG. 4illustrates two centrally located rails30each with a linear bearing45for guiding movement of bottom plate42and connecting plate44, and a plurality, e.g., four, additional vertical rails31, with two rails being outward of cylinder28and two rails being opposite the cylinder28with respect to rails30.

For the embodiment shown herein, the bottom plate is moved upward by the cylinder while the top plate remains stationary. In other embodiments, the top plate could be moved downward to compress the rod guide against the bottom plate and thereby assemble the guide on the rod. In still other embodiments, both the top plate and the bottom plate may be movable with respect to the frame to assemble the guide on the rod. The lever22is depicted exiting the side of the assembly. In other cases, the lever22may exit the top of the assembly, and may serve the same purpose.

In the intermediate position, the tag plate or bottom plate functions as a stop to prevent downward movement of the rod guide. When in this intermediate position, the top plate has a sufficiently wide slot so that the rod guide may pass through the top plate to allow the rod guide to engage the bottom plate. When the table is moved to the active or third position, each of the top plate and the bottom plate preferably includes a frustoconical surface to engage a portion of the rod guide, and at least one of these plates is movable axially in response to actuation of the cylinder to move the plates closer together, thereby compressing the two portions of the guide and assembling the guide on the sucker rod.

The powered tool disclosed herein is well suited for use at a well site to install guides as a rod is run into a well, but may also be used in a shop to install guides on sucker rods which are then shipped to a well site. In the latter case, the tool is preferably turned 90° so that the rod is generally horizontal when the guides are installed in the rods. Also, the hydraulic action of positioning the guide halves axially together to install the guide on a rod may be reversed so that guide halves are pressed axially apart to remove the guide from the rods.

Although specific embodiments of the invention have been described herein in some detail, this has been done solely for the purposes of explaining the various aspects of the invention, and is not intended to limit the scope of the invention as defined in the claims which follow. Those skilled in the art will understand that the embodiment shown and described is exemplary, and various other substitutions, alterations and modifications, including but not limited to those design alternatives specifically discussed herein, may be made in the practice of the invention without departing from its scope.