US2826254A - Packing for mandrel of testing tool - Google Patents

Description

March 11', 1958 F. E. .QNEILL PACKING FOR MANDREL TESTING TOOL Filed April '7, 1955 f/GL/ OINVENIOR. FRANK E. ONE/LL ATTORNEYS merino non MANDREL or TESTING TOGL Frank E. ONeill, Glendale, Califi, assignor, by mesne assignments, to Johnston Testers, Inc., Houston, Tex., a corporation of Texas Application April 7, 1955, Serial No. 499,926

4 Claims. (Cl. 166224) This application relates to a packing for use on tester mandrels for sealing above and below a test port.

In prior testing apparatus it was common practice to provide a sleeve packing within the housing above and below a test port therein, and move the mandrel longitudinally relative thereto to move a test port in the mandrel into and out of the zone between said sleeve packings in the manner shown in the patent to M. O. Johnston No. 2,661,802, issued in December 8, 1953. In practice it was found that the sleeve packing tended to bulge into the mandrel test ports as they moved through the packing, and the edges of the test ports tended to catch and rip the packing, thus requiring frequent packing replacement.

Another form of testing tool, such as that disclosed in the patent to M. O. Johnston No. 2,671,509, issued March 9, 1954, dicloses mounting O-rings on the mandrel above and below the test ports. However, the use of O-rings requires extremely close tolerances between the mating parts.

It is the principal object of this invention to provide a novel form of packing element for use on a mandrel which is movable longitudinally into and out of a sleeve housing.

A further object of this invention is to provide a novel packing element according to the preceding object wherein the packing element is mounted in an external groove on the mandrel and wherein the top and bottom edges of the packing element are relieved at their outer corners to prevent the packing element from flowing beyond the edges of the groove when the packing element is compressed.

A still further object of the invention is to provide a packing element according to the preceding objects wherein a centrally located V-shaped annular notch is cut into the outer surface of the packing element.

A preferred form of the invention is described in the following detailed specification, and illustrated by way of example in the accompanying drawings, wherein:

Fig. 1 is a longitudinal section of a mandrel and packer assembly embodying the principles of the invention.

Fig. 2 illustrates the mandrel shown in Fig. 1 partly drawn into a sleeve housing.

Fig. 3 is a fragmentary view illustrating a modified form of the packing element.

Referring now to the drawings, wherein similar reference numerals are used to denote the same elements throughout the various views shown, indicates a tubular mandrel adapted to be received within a housing 11 and movable longitudinally with respect thereto.

Three annular grooves 12, 13 and 14 are cut into the outer surface of the mandrel 10. The grooves 12, 13 and 14 are spaced from each other longitudinally of the mandrel 10. A plurality of test ports 15 are drilled laterally through the mandrel 10 between the grooves 12 and 13. The ports 15 connect the longitudinal passage 16 in the mandrel 10 with the exterior of the mandrel.

2,826,254 Patented Mar. 11, 1958 ice 2" A plurality of laterally extending tapped holes 17 are formed in the mandrel 10 between the grooves 13 and 14. Each of the holes 17 is provided with a threaded pipe plug 18 having a restricted orifice 19 formed therein.

Three rubber packing elements 20, 21 and 22 are mounted in the annular grooves 12, 13 and 14 respectively. The packing elements 20, 21 and 22 are bonded to the mandrel 10. The upper and lower corners of the packing element 20 are beveled in the manner shown at 23 and 24. Similarly, the upper and lower corners of the packing elements 21 and 22 are beveled in the manner shown at 25, 26, 27 and 28, respectively. Each of the packing rings is provided with an annular centrally located \l-shaped groove as indicated at 29, 30 and 31, respectively.

The bore 32 through the housing 11 is of a diameter slightly smaller than the external diameter of the packing elements 20, 21 and 22 when in their relaxed condition. The lower portion of the housing 11 is counterbored, as indicated at 33, to a diameter greater than the external diameter of the packing elements 20, 21 and 22. The counterbore 33 is joined to the bore 32 by a tapered section 34. The inclination of the taper 34 is considerably less than the inclination of the bevels 25 and 27 on the packing elements 21 and 22.

The modified form of packing element 35 shown in Fig. 3 has the same external configuration as the packing elements 21 and 22 with beveled upper and lower edges 36 and 37 and a V-shaped notch 38. The difference between this packing element 35 and the packing elements 21 and 22 is that this packing element 35 is elongated above and below the beveled portions 36 and 37 in the manner indicated at 39 and 40, respectively, and the width of the groove 41, in which the element is mounted, is accordingly increased. The packing element 35 being longer has more surface bonded to the mandrel 10, and the portions 39 and 40 thereof give additional protection against the rubber being forced beyond the edges of the groove 41, when the packing element is compressed within the bore 32 of the housing 11.

In the use of the device, the packing elements 20, 21 and 22 are mounted on the mandrel 10 and bonded thereto in the manner described above. The mandrel is then inserted in the housing 11 with all of the packing elements within the small diameter bore 32 thereof. It will be appreciated that the mandrel 10 and the housing 11 each are part of a testing tool, the remainder of which is not shown herein. When the testing tool is lowered into the well, the mandrel and sleeve are in the relative positions just described. When the test zone is reached, the testing tool is anchored in the well in a manner well known in the art and the mandrel 10 is moved downwardly relative to the housing 11. As the mandrel 10 moves downwardly, the packing element 22 moves into the counterbored portion 33 of the housing 11 and permits fiuid within the lower portion of the housing to bypass around the packing element 22 and enter the central passage 16 in the mandrel 10 through the restricted orifices 19. This is the position of the elements as illustrated in Fig. 2. Further downward movement of the mandrel 10 will move the packing element 21 into the countcrbore 33 to open the main test ports 15.

After the test has been completed, the mandrel 10 is moved upwardly relative to the housing 11. As the mandrel 19 is moved upwardly, first the packing element 21 moves into the restricted bore 32 (being compressed to fit therewithin by the tapered section 34) to close the main test ports 15, and subsequently the packing element 22 enters the bore 32 to close the restricted orifices 19.

As can be seen from the drawings, when the packing elements are compressed laterally to fit within the restricted bore 32, the rubber flows upwardly and downwardly to close the V-shaped notch and to straighten out the beveled edges of the packing element and form a regular cylinder completely sealing the annular space between the mandrel 10 and the housing 11. The initial bevel of the upper and lower edges of the packing elements and the external diameter of the packing elements and the bore 32 are so chosen that when in their compressed condition, the upper and lower edges of the packing elements will not extend beyond the edges of the grooves within which the packing elements are mounted.

While I have shown and described the preferred form of the invention, it is to be understood that various changes may be made in its construction by those skilled in the art, without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. For use in a testing tool having a tubular housing and a tubular mandrel movable longitudinally within said housing; an annular groove formed in the outer surface of said mandrel; an annular rubber packing element mounted in said groove and bonded to said mandrel, the upper end of said packing element extending outwardly from the outer surface of said mandrel and being beveled downwardly and outwardly, and the lower end of said packing element extending outwardly from the outer surface of said mandrel and being beveled upwardly and outwardly; a V-shaped annular notch cut into the outer surface of said packing element centrally thereof; said housing having a portion of restricted internal diameter smaller than the normal uncompressed external diameter of said packing element, a counterbored portion having a greater internal diameter than said normal uncompressed external diameter of said packing element, and a tapered portion joining said restricted portion and said counterbored portion, and a lateral port in said mandrel adapted to be packed off by said rubber packing element.

2. For use in a testing tool having a tubular housing and a tubular mandrel movable longitudinally within said housing; a plurality of annular grooves formed in the outer surface of said mandrel; an annular rubber packing element mounted in each of said grooves and bonded to said mandrel, the upper end of each of said packing elements extending outwardly from the outer surface of said mandrel and being beveled downwardly and outwardly, and the lower end of each of said packing elements extending outwardly from the outer surface of said mandrel and being beveled upwardly and outwardly; a V-shaped annular notch cut into the outer surface of each of said packing elements centrally thereof; said housing having a portion of restricted internal diameter smaller than the normal uncompressed external diameter of said packing elements, a counterbored portion having a greater internal diameter than said normal uncompressed external diameter of said packing elements, and a tapered portion joining said restricted portion and said counterbored portion, and a lateral port in said mandrel between said packing elements adapted to be packed off thereby.

3. For use in a testing tool having a tubular housing and a tubular mandrel movable longitudinally within said housing; annular grooves formed in the outer surface of and spaced longitudinally along said mandrel; an annular rubber packing element mounted in each of said grooves and bonded to said mandrel; the upper end of each of said packing elements extending outwardly from the outer surface of said mandrel and being beveled'downwardly and outwardly and the lower end of each of said packing elements extending outwardly from the outer surface of said mandrel and being beveled upwardly and outwardly; a V-shaped annular notch cut into the outer surface of each of said packing elements centrally thereof; said housing having a portion of restricted internal diameter smaller than the normal uncompressed external diameter of said packing elements, a counterbored portion having a greater internal diameter than said normal uncompressed external diameter of said packing elements, and a tapered portion joining said restricted portion and said counterbored portion; and a plurality of lateral test ports in said mandrel between said packing elements.

4. A testing tool comprising a tubular housing, a tubular mandrel movable longitudinally within said housing, an annular groove in the outer surface of said mandrel, an annular elastic packing element mounted in said groove and bonded to said mandrel, said packing element extending outwardly from the outer surface of said mandrel, said housing having a portion of restricted internal diameter less than the normal external diameter of said packing element, said housing having a concentric counterbored portion of internal diameter greater than said normal external uncompressed diameter of said packing element, said housing having a tapered portion joining said restricted portion and said counterbored portion, and said packing element having an annular recess formed therein to allow the packing element to flow into said recess when subjected to compression upon being fitted into said restricted portion of said housing, and a lateral port in said mandrel adapted to be packed off by said packing element.

References Cited in the file of this patent UNITED STATES PATENTS 654,073 Olinger July 17, 1900 1,625,095 Restein Apr. 19, 1927 2,005,955 Renoug June 25, 1935 2,352,423 Church June 27, 1944 2,544,623 Weiler Mar. 6, 1951 2,606,618 Page Aug. 12, 1952 2,629,444 O'Donnell Feb. 24, 1953 2,739,650 Hill Mar. 27, 1956

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