US2244104A

US2244104A - Sucker rod coupling

Info

Publication number: US2244104A
Application number: US251731A
Authority: US
Inventors: Jeremiah J Fitzpatrick
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-01-19
Filing date: 1939-01-19
Publication date: 1941-06-03
Anticipated expiration: 1958-06-03

Description

June 3, 1 J. J. FITZPATRICK SUCKER ROD COUPLING Filed Jan. 19, 1939 Patented June 3, 1941 UNITED STATES PATENT OFFICE lSUCKER ROD COUPLING Jeremiah J. Fitzpatrick, Oklahoma City, Okla.

Application January 19, 1939, Serial No. 251,731

6 Claims.

My invention relates to couplings for pump rod sections, and is designed for use particularly with sucker rod strings in deep wells, such as oil wells.

The prime object of the invention is the provision of a rod coupling which not only connects adjacent ends of rod sections, but also acts to cut accumulated paraffin from the walls of a string of production tubing.

Another object is to provide a combination rod coupling and paraffin scraper so designed that a minimum amount of fatigue, usually due to wall friction. is exerted upon the coupling portion of the device, and the greater amount of the fatigue is borne by the paraflin scraping element, the tendency of the coupling proper to become crystallized and to part under strain, thus being reduced to a minimum.

A further object of the device is the provision of a combination coupling and paraiiin scraper in which the scraping element, which receives the major portion of wear, is separate from the rod coupling element, and may therefore be formed of a metal particularly treated to stand the wear, while the coupling element proper may scraper in which the scraping element is replaceable when worn.

A further object is the provision of a combination rod coupling and paraffin scraper which also functions as a rod guide.

Other objects of the invention will be apparent by reference to the accompanying one-sheet drawing wherein like characters of reference designate like parts in all of the figures.

In the drawing:

Figure 1 is a perspective view of the rod coupling element of the device per se, the scraping element having been removed;

Figure 2 is an elevational view of the scraping element;

Figure 3 is a view similar to Figure 1 with the scraping element installed upon the coupling element.

Figure 4 is an elevational view of a box and box embodiment of the complete device;

Figures 5 and 6 are transverse sectional views taken substantially along the lines 55 and 66 respectively of Figure 4; and,

Figure 7 is a detail of one of a plurality of outstanding lugs which are carried by the coupling element.

One practical embodiment of the invention is illustrated in the drawing wherein the reference numeral l indicates as a whole a rod connecting element consisting substantially of two alined cylindrical rod receiving members 2 and 3 both threaded to receive adjacent ends of sucker rod sections, not shown. The members 2 and 3 may be constructed of the pin and box type as shown in Figures 1 and 3, or the device may be constructed in the box and box type and have two of the boxes 3 as illustrated in Figure 4. The members 2 and 3, or 3 and 3 as the case may be, are rigidly connected to each other by a plurality of integral vanes or ribs 4 which extend radially outward from a common center, which center is in alinement with the longitudinal axes of the members 2 and 3, or 3 and 3. The outer edges of the vanes 4 project outwardly beyond the exterior surface of the members 2 and 3 or 3 and 3, and their ends are each bevelled both laterally and longitudinally to form converging faces 5 and 6 separated by a knife-like parafiin cutting edge I. The faces 5-6 and the edge I meet at the exterior surface of the members. Intermediate their ends, each of the ribs 4 are provided with elongated notches 8 which are in radial alinement with each other for receiving a tubular paraffin scraping element 9, best seen in Figure 2. Both end walls H) of each notch 8 are bevelled, and both ends of the scraping element are similarly bevelled as indicated at H to fit the bevelled ends of the notches 8.

The scraping element 9 is generally tubular in form and has a longitudinal line of severance I! along which it has been cut. The longitudinal cut 12 allows the element to be sprung open sufficiently to permit its being passed over the outer edges of the ribs 4 and into the notches 8 of the element I. In installing the scraping element upon the coupling element, the cut I2 is placed along one of the ribs 4, and the cut is then closed by Welding and when so installed, the periphery of the element 9 lies flush with the outer edges of the ribs 4. Each end of the element 9 is provided with notches I3 which occur between the ribs 4, when the element is properly positioned, and the bevelled portions ll follow the entire contour of 4, and which are located one each between ad- Jacent ribs 4. Both ends of the lugs I4 are shaped similarly to that of theends of the ribs has above described, having bevelled side faces I5I6, and an intermediate knife-edge I1.

Operation The couplings are installed at desired intervals throughout the sucker rod string, and therefore function with each stroke of the'pump to keep the production tubing free of paraflin at the points of installation, foria distance equal to the length of the rod stroke. The paraffin along other portions of the tubing may be removed by raising the rod string a distance equal substantially to the interval between the installations.

It may readily be seen that the notches I3 prevent any possibility of the sleeve portion of the device fowling with the spaces between sections of production tubing, since no laterally ex-. tending surface is presented to the ends of the tubing sections. The ends of the ribs 4 and lugs I4 being bevelled act to prevent their hanging between the tubing sections.

Operative tests have shown that a much better result is obtained by forming the device so that the leading ends of the ribs and lugs, or actually the cutting edges I and I1, precede the cutting edges of the sleeve 9 in contacting the parafiin, than could be obtained by utilizing only the cutting edge of the sleeve for removing the paraflin. The cutting edges 1 and I 1 act as plows for loosening the paraflin, and the following cutting edges of the sleeve can then better remove the loosened parafiin.

The lugs I4 perform a further function in helping to protect the sleeve against collapse due to side thrust occasioned by the well being crooked and the tool therefore being dragged violently against a side Wall of the tubing. This feature might at first glance seem trivial, but tests have shown thatioads of 18,500 pounds are common in deep pumping wells, and that at the time the rods are reversed in motion during the pumping stroke, a 5000 pound blow is usually delivered. This blow together with the load present upon the rods could well collapse a sleeve type paraifln scraper unless the blow against the tubing wall is distributed in the coupling over a considerable length of span. The end portions of the ribs 4- and the lugs I4 together act to receive a portionof this shock, and thereby make it possible to provide a sleeve type scraper with adequatefiuid passage through the sleeve and between the ribs. The lugs I4 prevent the sleeve from being flattened between the ribs 4, when the blow is delivered.

Should the sleeve 9 become worn or damaged, it may easily be cut loose from the element or body I and a new one welded in place.

It is pointed out that not only does the present device act to couple rod sections and remove fparaifin, but it also functions as a rod guide for preventing wear between the production tubing and the sucker rod string. The construction of the coupling-element I and the scraping elementof two difierent metals permits the sleeve to be made of a metal which will glaze under friction with the tubing and will not become rough or gauld. The distance from end to end of the ribs is such that considerable bearing surface is presented against the tubing.

I claim:

1. A sucker rod coupling, including: upper and lower rod connecting members having their axes aligned; longitudinally extending vanes, their ends connecting the members and their adjacent edge portions integrally connecting each other in substantial alignment with the axes of said rod connecting members, said vanes extending radially outward from their point of interconnection past the peripheries of the rod connecting members, both ends or each vane being bevelled inwardly to the periphery of one of said rod connecting members and also being bevelled laterally to'form sharp outwardly presented paraflin cutting edges, each vane having a longitudinally extending indenture in its outer edge; and, av

tubular sleeve seated around the vanes within said indentures, its periphery lying flush with the outer edges of the vanes, said sleeve having notches in its ends which are located between the vanes and which. act to prevent lodgement of the device in interstices of tubing joints, said sleeve ends being bevelled inwardly to form continuous paraflin cutting edges.

2. A sucker rod coupling, including: upper and lower rod connecting members having their axes aligned: longitudinally extending vanes, their ends connecting the members and their adjacent edge portions integrally connecting each other in substantial alignment with the axes of said rod connecting members, said vanes extending radially outward fromtheir point of interconnection past the peripheries of the rod connecting members, both ends of each vane being bevelled inwardly to the periphery of one of said rod con- I necting members and also being bevelled laterally to form sharp outwardly presented paraifin cutting edges, each vane having a longitudinally extending indenture in ,its outer edge; and, a re movable tubular sleeve seated around the vanes within said indentures, its periphery lyingiiush with the outer edges of the vanes, said sleeve having notches in its ends which are located between the vanes and which act to prevent lodgement of the device in interstices of tubing joints, said sleeve ends being bevelled inwardly to form continuous parafiin cutting edges.

3. A sucker rod coupling, including: upper and lower rod connecting members having their axes 'aligned; longitudinally extending vanes, their ends connecting the members and their adjacent edge portions integrally connecting each other in substantial alignment with the axes of said rod connecting members, said vanes extending radially outward from their point of interconnection past the peripheries of the rod connecting members, both ends of each) vane being bevelled inwardly to the periphery of one of said 'rod connecting membersand also being bevelled laterally to form sharp outwardly presented parafiin cutting edges, each vane having a longitudinally extending-indenture in its outer edge;

a tubular sleeve seated around the' vanes Within said indentures, its periphery lying flush with the outer edges of the vanes, said sleeve having notches in its ends which are located between the vanes and which act to prevent lodgement of the device in interstices of tubing joints, said sleeve ends being bevelledinwardly to form continuous paraflln cutting edges; and, radially spaced outwardly projecting lugs carried by the rod connecting members for contacting the inner wall of a tubing string, both ends of each lug being bevelled inwardly to the periphery of its supporting rod connecting member and also being bevelled laterally to form sharp outwardly presented paraffin cutting edges.

4. A sucker rod coupling, including: upper and lower rod connecting members having their axes aligned; longitudinally extending vanes, their ends connecting the members and their adjacent edge portions integrally connecting each other in substantial alignment with the axes of said rod connecting members, said vanes extending radially outward from their point of interconnection past the peripheries of the rod connecting members, both ends of each vane being bevelled inwardly to the periphery of one of said rod connecting members and also being bevelled lateral: ly to form sharp outwardly presented paraflin cutting edges, each vane having a, longitudinally extending indenture in its outer edge; a removable tubular sleeve seated around the vanes within said indentures, its periphery lying flush with the outer edges of the vanes, said sleeve having notches in its ends which are located between the vanes and which act to prevent lodgement of the device in interstices of tubing joints, said sleeve ends being bevelled inwardly to form continuous parafiin cutting edges; and, radially spaced outwardly projecting lugs carried by the rod connectingmembers for contacting the inner wall of a tubing string, both ends of each lug being bevelled inwardly to the periphery of its supporting rod connecting member and also being bevelled laterally to form sharp outwardly presented parafiln cutting edges.

5. Organization as described in claim 2 in which the sleeve is severed along a single longitudinal line of cleavage so that it may be expanded to pass over the ends of the varies in reaching its position in the notches therein.

6. Organization as described in claim 2 in which the sleeve is severed along a single longitudinal line of cleavage so that it may be expanded to pass over the ends of the vanes in reaching its position in the notches therein, and

means for connecting the edges of said sleeve along the line of cleavage.

JEREMIAH J. FI'IZPA'I'RICK.