US 3554280 A
Description (OCR text may contain errors)
United States Patent lnventor Andrew J. Tucker Mesquite, Tex.
Appl. No. 792,674
Filed Jan. 21, 1969 Patented Jan. 12, 1971 Assignee Dresser 1ndustries,1nc. Dallas, Tex.
a corporation of Delaware WELL PACKER AND SEALING ELEMENTS THEREFOR 9 Claims, 6 Drawing Figs.
Int. Cl E2 lb 23/00 Field of Search References Cited UNITED STATES PATENTS 1,395,718 11/1921 Mack 1,395,719 11/1921 Mack 166/196X 2,612,953 10/1952 Morgan et a1. 166/196X 2,845,286 7/1958 Case et al. 277/124 3,227,462 1/1966 Tamplen 166/196 3,181,614 5/1965 Brown 166/122 3,357,493 12/1967 Conrad 166/134 Primary Examiner-James A. Leppink AnomeysRobert W. Mayer, Daniel Rubin, Peter J. Murphy,
Frank S. Troidl, Roy L. VanWinkle and William E. Johnson, Jr.
1 WELL 'PACKER AND SEALING ELEMENTS THEREFOR BACKGROUND OF THE INVENTION This invention relates generally to well packers. More particularly, but not by way of limitation, this invention relates to a well packer having an improved packing element thereon.
Well packers constructed in the past have beenused-in the well bores, to either entirely plugthe well bore or to form an annularseal between the wall of the well bore and a pipe extending therethrough. In most instances, the well packer will include a mandrel that extends through the packer and about which, an annular deformable packing element is mounted. Some difficulty has been encountered in prior known well packers in preventing theextrusion of the deformable packing element axially along the space between theexterior of the packer and the wall of the well bore. To alleviate this problem, the packing elements are preferably constructed from a relatively hard natural or synthetic rubber or similar deformable material.
When such materials are used, difficulty has been encountered in forming a seal between the interior of the packing element and the mandrel while at the same time forming a fluidtight seal between ,the Iexteriorthereof and'the well'bore wall. The difficulty is particularly acute cluring the initial deformation of the packing element. i
SUMMARY OF THE THE INVENTION well packers and the like wherein the packing element comprises a generally cylindrical bodyof deformable material having an annular recessin its inner wall and an' annular member of deformable material located inthe annular recess.
In another aspect,- this invention provides an improved packer for use in 'well bores and the like including a mandrel, upper and lower anchoringmeans on the mandrel and means for settingthe anchoring means in the well bore. A generally cylindrical packing body encircles the mandrel between the upper and lower anchoring means; The body is formed of a deformable material and hasan annular recess in its inner wall. ,An annular member of deformable material is located in the recess encircling the mandrel. The annular member is arranged to sealinglyv engage the mandrel to form a fluidtight seal upon deforrnationof the body.
One objectof theinvention is to provide an improved packing element for packers wherein a fluidtight seal between the packing element and mandrel can be attained during the initial deformationof the packing element. v
Another object of the invention is toprovide an improved packer for use in well bores that includes a packing element that is arranged to seal not only against the well bore wall but to also seal against the mandrel. I
The foregoing and additional objects and advantages of the invention will become more apparent as the following detailed description is read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a wellpa'cker constructed in accordance with the invention;
FIG; 2 is a cross-sectionalview similar to FIG. 1, but showing the wellpackei' in'the set condition in a well conduit.
FIG. 3 is an enlarged cross-sectional view of a portion of the packer of FIG. 1 illustrating the'packing element during the initial stages of deformation.
FIG. 4 is a viewsirnilar to FIG. 3,but showing the packing element almost completely deformed. t
FIG, 5 is an enlarged, cross-sectional view of a modified packing element constructed in accordance with the invention.
FIG. 6 is a view similar to FIG. 5, but showing another packing element also constructed in accordance with'the invention.
' verted in their assembly on the packer 10. The s I 2 DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing in FIG. 1 in particular, shown therein and generally designated by the reference character 10 is a packer assembly constructed in accordance with the invention. The packer assembly I0 illustrated is generally known in the oil field art as a bridge plug.
The packer assembly 10 includes a mandrel 12 having a plugged lower end 14. It will be understood that the plug formed by the lower end 14 may be located in the mandrel 12 in any desired position. For example, the closure or plug is sometime located at the upper end of the mandrel l2.
' In the packer assembly 10, the upper end of the mandrel 12 is connected with an inner member 16 of a setting mechanism. The setting mechanism is not illustrated in detail but is well known in the art and also includesan outer settingsleeve 18 which is slidable relative to the inner member 16.
Disposed in encircling relationship to the mandrel I6 is an upper anchor mechanism 20 that includes a plurality of toothed slips 22. Eachof the slips 22 has an inner tapered surface 24.
The upper anchor mechanism 20 also includes an expander member 26 having an upwardly and inwardly tapering surface 28 that mates with the inner tapered surfaces 24 on the slips 22. The slips 22 and the expander 26 are movable on the man drel l2 and movable relative to each other. The movement therebetween moves the slips 22 radially outwardly relative to the mandrel l2.
The packer assembly 10 also includes a lower anchor mechanism 30 that comprises a plurality of toothed slips 32. Each of the slips 32 has a tapered inner surface 34.
The lower anchor mechanism also includes an expander 36 having a downwardly and inwardly tapered surface 38 mating with the surfaces 34 on the slips 32. The slips 32 and expander 36 are slidably mounted on the mandrel l2 and are movable relative to each other. Movement between the slips 32 and the expander 36 with the surfaces 34 and 38in engagementmove's the slips 32 radially outwardly relative to the mandrel 12.
Various means (not shown) are usually provided to retain the various components of packer-assemblies in their runningin positions and to control the relative movement of the com ponents. For example, it is well known to utilize shear pins (not shown) having different shear values between the maridrel, slips and-expanders to provide for the retention of and to control the time of movement of the slips and expanders, relative to the mandrel and relative to each other.
Disposed between the upper and lower anchor mechanisms" 20-and 30, respectively, is a packing element 40. The packingelement 40 includes a generally cylindrical body 42havi'rig tapered upper and lower ends and 46. It will'als'o be noted that a triangular shaped, annular recess 48 is provide e interior of the body 42 The body 42 is for'riie'd from a deformable material, such as rubber, synthetic rubber oit'jthei suitable material.
The packing element 40 also includes upper and lo nular support members 50 and 52, respectively. Thsu port members 50 and 52 are identically constructed;'al"
bers 50 and 52 each include a tapered inner surfaces h at in engagement with the tapered surfaces 44 ana'asarinebaay 42.
OPERATION OF THE PREFERRED EMBODIMENT To place the packer assembly in use, the packer assembly 10 is connected through the setting mechanism with a wireline (not shown) and lowered into the casing 60 that is disposed in a well bore (not shown). Upon reaching the desired depth in the well bore for setting the packer assembly 10, the setting device is actuated pulling the inner member 16 upwardly and lowering the outer sleeve 18 simultaneously.
As previously mentioned, the mandrel 12 is connected with the inner member 16 so that the mandrel 12 moves upwardly therewith, As clearly shown in FIG. 2, the outer sleeve 18 is in engagement with the upper slips 22 forcing the upper slips downwardly relative to the upper expander 26. The relative movement between the upper slips 22 and expander 26 moves the slips 22 radially outwardly until the teeth thereon holdingly engage the casing 60.
The upward movement of the mandrel 12 moves the lower end 14 upwardly carrying the lower slips 32, the lower expander 36 and the packing element 40 upwardly against the upper expander 26. It can be appreciated that the relative movement between the lower expander 36 and upper expander 26 will apply a force on both ends of the packing element 40, deforming it outwardly into sealing engagement with the casing 60 as illustrated in FIG. 2. The upward movement of the lower expander 36 continues until the packing element 40 is completely deformed at which time the upward movement terminates and the slips 32 move relative to the lower expander 36.
Relative movement between the lower slips 32 and lower expander 36 moves the lower slips radially outwardly into holding engagement with the casing 60. At this time, the packer assembly 10 is set in the casing 60 as illustrated in FIG. 2.
FIGS. 3 and 4 illustrate in more detail the deformation of the packing element 40 during the setting of the packer assembly 10. As shown in FIG. 3, deformation of the body 42 has been initiated by the movement of the upper and lower expanders 26 and 36 relatively together. The triangular-shaped, annular recess 48 in the body causes the body 42 to buckle or node" outwardly at the exterior thereof immediately adjacent the recess 48.
As the body 42 nodes outwardly, the surfaces of the body 42 adjacent the recess 48 move relatively together exerting a force inwardly on the outer surfaces of the annular member 58. The result of such forces is to move the annular member 58 radially inwardly toward the mandrel 12, forming a fluidtight seal therebetween with very little deformation of the body 42.
As may also be seen in FIG. 3, the support members 50 and 52 have been deformed slightly forcing the metallic reinforcing members 56 relatively outwardly toward the casing 60.
As shown in FIG. 4, the packing element 40 is almost completely deformed and it can be, seen that the more deformation that occurs in the body 42, the tighter the annular member 58 is held in engagement with the mandrel 12. Thus, the structure described insures a positive fluidtight seal between the mandrel 12 and the packing element 40 at all times during deformation of the body 42.
At the stage of setting of the packer assembly 10 shown in FIG. 4, the support members 50 and 52 are almost completely deformed with the outermost edges of the reinforcing members 56 in initial engagement with the casing 60 providing a backup for the deformable portions of the support members 50 and 52. Thus, the support members 50 and 52 and the body 42 are prevented from extruding axially past the expanders 26 and 36.
From the foregoing, it can be seen that the packing element 40, having the annular recess 48 formed in the interior thereof, provides a controlled buckling or noding effect which precisely controls the point of sealing with the casing 60 and at the same time provides an inwardly directed force on the annular member 58 forming a positive, fluidtight seal between the mandrel 12 and the packing element 40. The packing element 40, as constructed and when deformed, assures a positive fluidtight shut off of the annular space between the mandrel l2 and the casing 60 when the packer assembly 10 is set as described.
FIG. 5 illustrates a modification of the body 42 that is designated by the reference character 142. As illustrated, the body 142 is to be constructed from a deformable material such as rubber, synthetic rubber or other suitable material. The body 142 includes upper and lower tapered surfaces 144 and 146 so that the body 142 can be used in the packer assembly 10 in lieu of the body 42. The interior of the body 142 is provided with an annular recess 148 that has a generally semicircular cross section. Fitted within the recess 148 is an annular member 158 that is also constructed from a deformable material and has a cross section fitting the recess 148.
As previously mentioned, the body 142 can be substituted for the body 42 in the packer assembly 10. The triangular form of the recess 48 and annular member 58 is preferred because of the more efficient force loading that occurs on the member 58 when the body 42 is deformed, but it will also be obvious that the annular member 158 will be forced inwardly, that is, toward the mandrel 12 upon deformation of the body 142 as previously described in connection with the body 42. It will also be noted that the body 142 will node" at a point opposite the annular recess 148 thereby providing controlled deformation of the body 142 during setting of the packer assembly.
FIG. 6 illustrates still another embodiment of the packing element that is designated by the reference character 242. The body 242 is also to be constructed from a deformable material and is provided with upper and lower tapered surfaces 244 and 246, respectively, so that the body 242 can be used in the packer assembly 10 in lieu of the body 42. The body 242 is provided with an interior annular recess 248 which has a generally rectangular cross section.
An annular member 258 constructed from a deformable material and having a rectangular cross section is fitted into the annular recess 248. Of the three configurations described for the annular member, the rectangular cross section is the least preferred since the forces developed thereon are not as efficient in moving the annular member 248 toward the mandrel 12 as is either the triangular shaped annular member 58 or the semicircular shaped annular member 158. If the rectangular cross section member 248 is used it is preferred that the member 258 be constructed from a material that is somewhat softer than the body 242 and thus more easily deformed. It can be appreciated that the body 242, when substituted into the packer assembly 10 will node at a point opposite the annular recess 248 thus providing controlled deformation of the body 242.
The embodiments described hereinbefore are presented by way of example only and it will be understood that many changes and modifications can be made'thereto without departing from the spirit and scope of the invention.
l. A packing element for sealing between the mandrel of well packers and the like and the casing in a well bore, said packing element comprising:
a generally cylindrical body of deformable material, said body having an annular recess in its inner wall; and
an annular member of substantially incompressible,
deformable material located in said annular recess and engaging said body, said annular member sealingly engaging the mandrel upon deformation of said body.
2. The packing element of claim 1 wherein said annular member is more easily deformed than said body.
3. The packing element of claim 1 wherein said recess and annular member have substantially triangular cross sections.
4. The packing element of claim 1 wherein said recess and annular member have substantially semicircular cross sec tions.
5. An improved well packer including a mandrel, upper and lower anchoring means on the mandrel and means for setting the anchoring means in a well bore, the improvement comprisa generally cylindrical packing body encircling the mandrel between the upper and lower anchoring means, said body, upon application of deformation forces, buckling into sealing engagement withthe well bore wall and having an annular recess in its inner wall; and
an annular member of substantially incompressible,
deformable material located in said recess and encircling the mandrel and engaging said body, said annular member sealingly engaging the mandrel upon deformation of said body.
6. The packer of claim 6 wherein said annular member is more easily deformable than said body and said annular recess and annular member have rectangular cross sections.
7. The packer of claim 6 wherein said recess and annular member have substantially triangular cross sections.
8. A packing element for well packers and the like, said packing element comprising: 7
a generally cylindrical body of deformable material, said body having an annular recess in its inner wall;
an annular member of deformable material located in said annular recess;
an annular support member adjacent each end of said body,
said support members being constructed of deformable material; and i metallic reinforcing means supportingly engaging each of said support members.
9. An improved well packer including a mandrel, upper and lower anchoring means on the mandrel and means for setting the anchoring means in a well bore, the improvement comprising:
a generally cylindrical packing body encircling the mandrel between the upper and lower anchoring means. said body being deformable into sealing engagement with the well bore wall and having an annular recess with a substantially triangular cross section in its inner wall;
an annular member of deformable material with a substantially triangular cross section located in said recess and encircling the mandrel, said annular member sealingly engaging the mandrel upon deformation of said body;
an annular support member of deformablegmaterial located between said body and each of the upper and lower anchoring means; and
a metallic reinforcing member located between said support members and each of the upper and lower anchoring means, said reinforcing members engaging the well bore wall upon deformation to support said support members and prevent axial extrusion of said body between said packer and the well bore wall.