Multi-piece rod guide for wells

Abstract

A guide for sucker rods comprises a cylindrical shape including an orifice for the sucker rod and four protrusions extending outwardly therefrom. The guide utilizes a symmetrical two-piece design wherein each piece comprises a semi-cylindrical shape, with one full protrusion extending the length of the guide and two half protrusions extending half the length of the guide and also beyond the semi-cylindrical profile. These two pieces are attached to each other by means of an interference fit between two pairs of interlock surfaces, one pair of which is located on the inner surface of the portion of the half-protrusions extending beyond the semi-cylindrical profile, and the other pair of which is located on the outer surface of the guide on the opposite side from the two half protrusions. Epoxy is injected into grooves along the internal surface of the cylindrical shape by means of ports extending through the rod guide.

1 . A guide for sucker rods comprising:
 a cylindrical profile having a first end, a second end, an outer surface, and an inner surface;   at least one internal groove along the inner surface; and   a plurality of protrusions extending from the outer surface, along the longitudinal axis of the cylindrical profile, wherein the plurality of protrusions terminate gradually to form a first plurality of bow shapes at the first end and a second plurality of bow shapes at the second end,   wherein the sucker rod guide is formed from a plurality of semi-cylindrical pieces, wherein the plurality of semi-cylindrical pieces are interference fit to each other to form the cylindrical profile and the plurality of protrusions, and wherein adhesive applied to the at least one internal groove secures the plurality of pieces to the sucker rod.   
     
     
         2 . The guide of  claim 1 , further comprising at least one port on the outer surface, wherein the at least one port defines a path from the outer surface to the at least one internal groove. 
     
     
         3 . The guide piece of  claim 1 , wherein the guide comprises a thermoplastic polymer. 
     
     
         4 . The guide piece of  claim 3 , wherein the thermoplastic polymer comprises a polyphthalamide having at least 33% glass reinforcement. 
     
     
         5 . The guide piece of  claim 1 , wherein the interference fit comprises a plurality of interlocking wedges fitting to a plurality of interlocking cavities. 
     
     
         6 . A guide for sucker rods comprising two pieces disposed about a longitudinal axis and
 defining an orifice therethrough, each of the two pieces comprising:
 a semi-cylindrical profile having a first end and a second end; 
 an outer surface and an inner surface, the inner surface comprising at least one internal groove; 
 a first protrusion extending from the outer surface and along the longitudinal axis of the semi-cylindrical piece, wherein the first protrusion terminates at the first end and the second end; 
 a second and third protrusion extending from the outer surface and along the longitudinal axis, wherein the second and third protrusions each terminate at the first end and halfway between the first end and the second end, and wherein a portion of the second and third protrusions extends circumferentially beyond the semi-cylindrical profile; 
 a first pair of interlock surfaces, wherein the first pair of interlock surfaces is located on either side of the first protrusion, near the second end of the piece; and 
 a second pair of interlock surfaces, wherein the second pair of interlocking surfaces is located on the portion of the second and third protrusions extending beyond the semi-cylindrical profile; 
   wherein the first pair of interlock surfaces of one of the two pieces forms an interference fit with the second pair of interlock surfaces of the other of the two pieces, wherein the second pair of interlock surfaces of one of the two pieces forms an interference fit with the first pair of interlock surfaces of the other of the two pieces, and wherein adhesive applied to the at least one internal groove secures the pieces to the rod.   
     
     
         7 . The guide of  claim 1 , wherein each of the two guide pieces further comprise a plurality of ports on the outer surface, wherein the plurality of ports define a path from the outer surface to the at least one groove of the inner surface. 
     
     
         8 . The guide pieces of  claim 1 , wherein the first protrusion of each of the guide pieces terminates in a bow shape, forming an edge at the first end and the second end of the first protrusion. 
     
     
         9 . The guide pieces of  claim 3 , wherein the second and third protrusion of each of the guide pieces terminate in a bow shape at the first end, forming a second and third edge at the first end. 
     
     
         10 . The guide pieces of  claim 1 , wherein the first pair of interlock surfaces comprises a wedge-shaped cross-section. 
     
     
         11 . The guide pieces of  claim 5 , wherein the second pair of interlock surfaces comprises a negative space having the wedge-shaped cross-section. 
     
     
         12 . The guide piece of  claim 1 , wherein the guide comprises a thermoplastic polymer. 
     
     
         13 . The guide piece of  claim 7 , wherein the thermoplastic polymer comprises a polyphthalamide. 
     
     
         14 . A method of fitting a rod guide to a sucker rod, comprising:
 molding a plurality of guide pieces having a semi-cylindrical profile and at least one interlock surface;   transporting the plurality of guide pieces to an installation location having a sucker rod;   applying an adhesive to an internal surface of the plurality of guide pieces;   aligning the plurality of guide pieces with each other along the sucker rod;   engaging the interlock surfaces of the plurality of guide pieces with each other; and   applying force to the plurality of guide pieces such that the interlock surfaces deform each other to create an interference fit rod guide along the sucker rod.   
     
     
         15 . The method of  claim 14 , wherein the step of aligning the plurality of guide pieces with each other along the sucker rod comprises making a locating mark on the sucker rod and aligning the plurality of guide pieces therewith. 
     
     
         16 . The method of  claim 14 , wherein the step of molding a plurality of guide pieces comprises injecting a thermoplastic polymer into a mold, the mold comprising a negative shape equivalent to the plurality of guide pieces. 
     
     
         17 . The method of  claim 16 , wherein the thermoplastic polymer comprises a polyphthalamide. 
     
     
         18 . The method of  claim 14 , wherein the step of applying the adhesive to the plurality of guide pieces comprises filling at least one internal groove with an epoxy. 
     
     
         19 . The method of  claim 18 , further comprising the step of removing excess epoxy from a plurality of external ports in communication with the plurality of internal grooves. 
     
     
         20 . The method of  claim 14 , wherein the step of applying force to the plurality of guide pieces comprises a hydraulic ram having steel shoes, wherein the steel shoes comprise a negative shape equivalent to the plurality of guide pieces.