US2793917A

US2793917A - Sucker rod protectors

Info

Publication number: US2793917A
Application number: US397813A
Authority: US
Inventors: Warren F Ward
Original assignee: Individual
Current assignee: Individual
Priority date: 1953-12-14
Filing date: 1953-12-14
Publication date: 1957-05-28
Anticipated expiration: 1974-05-28

Description

May 28, 1957 O w. F. WARD 2,793,917

SUCKER ROD PROTECTORS Filed Dec. 14, 1953 IN V ENTOR.

WAR EN 1 WARD United States Patent SUCKER ROD PROTECTORS Warren F. Ward, Dallas, Tex.

Application December 14, 1953, Serial No. 397,813

3 Claims. (Cl. 308-4) This invention relates to protectors or guides for use on sucker rods in pumping oil wells.

It is general knowledge to those skilled in the art that a great amount of destructive wear occurs on both the rod string with its couplings and the inner face of the tubing in which the rod string reciprocates while the pumping operation is in progress. This wear is very great even in so-called straight wells and is vastly accentuated in crooked wells, or directional wells designedly drilled off the vertical.

It is also known that electrical forces are present underground which frequently set up electrolytic action that hastens disintegration or destruction of the rod string and/or the tubing. These destructive actions are normally concentrated at the rod couplings or where the rods wear against and maintain contact with the tubing. These wear points are also the origination points for friction and drag loads opposing reciprocation of the rod string. These factors increase the power requirements for pumping a given Well and increase the maintenance cost due to earlier and repeated servicings of worn and failing parts. In many wells sulphides and other elements damaging to steel rods and tubings are present, and their deleterious actions are accelerated and intensified by the electrical, frictional, and other forces present. Among such other forces are pressures in the fluid column in the tubing, and elevated, varying temperatures of the elements being agitated and pumped out of the well. In deep wells pressures may be several thousand pounds per square inch, particularly where large volumes of salt and sulphur laden water must be removed from the well in order to keep pressures ofi the producing formation so the oil will migrate toward and into the well bore.

I am aware of many previous attempts at solution of these problems by providing rod guides of wood, nibber, or other materials, which generally have been unequal to the problems encountered. Illustrative of these is the guide disclosed in my prior U. S. Patent No. 2,604,364 in which a spring steel retainer or clip is embedded in rubber. The purpose of the clip in that patent is to secure the guide in place on the rod by maintaining, over the life of the guide, a constant gripping of the rod. The rubber of the guide referred to is designed to protect the spring steel clip from the elements encountered and to provide insulation between the rod string and tubing. Protection of the clip initially is adequate, but the rubber is not impervious to elements that attack and embrittle the clip, causing it to break. The guide then frequently drops down onto the coupling below it, or floats in the moving fluids in the tubing, and wedges about a coupling, perhaps causing rod breakage, making the guide responsible for causing the very sort of difficulty it was intended to prevent.

My present invention provides a rod guide which overcomes these difficulties and is simple in design, economical to manufacture, easy to install, and durable in use under the widest of varying conditions.

My novel guide is made of a single element, which is designed to provide ample passageway for the fluids of the well thereabout when installed on the rod, and which possesses the inherent quality of providing the necessary grip on the rod to retain its predetermined strategic position with respect to protecting the parts from contact and wear. The material of my guide is highly resistant to abrasion, electrolytical forces, oils, acids, salts, sulphur, sulphides, and other elements to which it is subjected. It is highly impervious to penetrations by these elements and is little affected by the temperatures and pressures encountered. The material is sufficiently flexible to permit being distorted to embrace the rod yet rigid enough, and with memory of original shape and urge to return thereto, to provide continuous gripping of the rod to maintain its position thereon. Nylon (du Pont #10,001) molded into the desired form meets the requirements set forth, and for purposes of brevity, reference herein further is made of this material; however it is contemplated that I may use other materials possessing the essential and desired properties, and all such are meant to be included in the scope of the invention.

In the accompanying drawings:

Fig. I is a perspective view of a preferred form of my guide mounted on a section of a pump rod.

Fig. II is a section along line 22 of Fig. I.

Like references indicate similar parts in the several views in which 3 is a section of pump rod, 4 is a guide composed preferably of molded nylon and having fluid ways or passages 6 about its peripheral face. The maximum diameter of the guide, as at 7, is sufiiciently smaller than the inside diameter of the well tubing, not shown, with which it is designed to operate to permit of free motion therein. 8 is a slotted opening in one side of my guide, slightly less in width than the diameter of rod 3, while 9 is a longitudinal opening through guide 4 slightly smaller in cross section than rod 3. 1010 are ledges along the faces of slot 8 which project toward each other to form a section of slot 8 more narrow at its intersection with opening 9 than at its outer lips 11-11 for purposes set forth in more detail later herein.

In operation I proceed as follows: I preferably mold my guide as shown of a material, such as nylon, having the characteristics as described herein. I then apply the guide slot 8 as by hand to rod 3, the rod and slot being of such relative sizes, and the material of my guide of such resilience, that a hand pressure is suflicient to cause the slot to receive the rod and embrace the same with sufficient force to maintain the parts in this relation While a suitable mounting tool or applicator is brought into operation to cause the rod to pass inwardly of the guide through the slot and past the ledges 1010 into the opening 9 of the guide. The parts are now assembled, the guide is distorted from its original molded shape and will, by reason of its memory of that shape and urge to return thereto, grip and secure itself upon the rod with suflicient tenacity to prevent dislodgement during its service life.

The slot 8, together with passages 6, will provide amply for the flow of the fluids upward past the guide as they are pumped from the well. The fluid ways or passages 6, in addition to providing passage for well fluids, also serve to distribute the stresses about the body of the guide when it is distorted to receive the rod.

All modifications of shape and form of my guide, and of material from which it is made are intended to be included as fall within the scope of the following claims.

What I claim is:

1. In oil well equipment, a guide to be attached to a sucker rod, said guide comprising a cylindrical deformable homogeneous body of nylon, said body having a longitudinal bore therethrough to receive the rod and having a longitudinal slot through the body and communicating with said bore, the diameter of the bore being slightly less than the diameter of the sucker rod, the width of the slot beingnarrower at its juncture withjthe bore than its Width near the outer periphery of the body, and th e Width of the slot at its juncture with the bore being "narrower than the diameter of the bore, whereby the guide when attached will retain a spring-like 'grip on the rod Without auxiliary clamping means.

" 2. In a guide as set forth in claim 1, said body having one or more longitudinally disposed passages comprising rounded recesses inthe outer surface'of the body.

3. In a guide as set forth in claim 1, the width of the slot at the outer periphery of the body being at least equal to the diameter of the rod.

References Cited in the file of this patent UNITED STATES PATENTS 1,560,468 Dodson Nov. 3, 1925 2,153,787 Anderson Apr. 11, 1939 2,436,994 Gillespie Mar. 2, 1948 2,604,364 Ward July 22, 1952 2,604,365 Howard July 22, 1952 2,622,949 Cotchett Dec. 23, 1952