US3128826A

US3128826A - brown

Info

Publication number: US3128826A
Authority: US
Publication date: 1964-04-14
Anticipated expiration: 1981-04-14

Description

April 14, 1964 C. C. BROWN WELL PACKER ASSEMBLIES Filed Nov. 21, 1960 I5 C I50.

19 I6 I8 IBJ 21a 3 Sheets-Sheet l CIERO C. BROWN ATTORNEYS April 14, 1964 c. c. BROWN v 3,128,826

WELL PACKEIR ASSEMBLIES Filed Nov. 21, 1960 3 Sheets-Sheet 2 ace/e0 c. BROWN INVENTOR.

A TTORNEV April 14, 1964 c. c. BROWN 3,128,826

WELL PACKER ASSEMBLIES Filed Nov. 21, 1960 3 Sheets-Sheet 3 ATTM/YEVS 0/05/20 4. BROWN INVENTOR.

BY gr 7! M r United States Patent 3,128,826 WELL PACKER ASEMBLTE Cicero C. Brown, 8490 Katy Road, Houston, Tex. Filed Nov. 21, 1%9, Ser. No. 70,548 1th Ciairns. (Cl. 166-134) This invention relates to new and useful improvements in well packer assemblies.

One object of the invention is to provide an improved well packer assembly of simple and inexpensive structure which may be employed either as a weight-set packer, where the weight of the tubing is imposed upon the packing element, or as a tension-set packer wherein upward tension on the pipe string which carries the packer is employed to maintain the assembly in its set position.

An important object of the invention is to provide an improved well packer assembly including a flexible sleevelike packer element and an anchoring means, together with a coil spring mounted to co-act with said element and anchoring means in a manner to maintain the packing element in its unset position during lowering and raising and to assist in the release of the packing element when the assembly is to be removed from the well here.

A further object is to provide a well packer assembly which may be used as a weight-set or a tension-set packer and which is constructed so that the difierential of pressure across the packing element of the assembly will maintain said element in its sealing position, the assembly also including a simple type holddown means which is incorporated within the packing element and which functions to prevent displacement of the assembly in one direction by an unbalanced pressure across the packer.

Still another object is to provide a packer assembly which is applicable for use with a gripping unit which is associated with the supporting slips of the packer anchoring means, with said gripping unit being constructed to positively lock the gripping slips against movement within the pipe when the anchoring means is to be set Within the well pipe.

The construction designed to carry out the invention will be hereinafter described, together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

FIGURE 1 is a view, partly in section and partly in elevation, of a well packer assembly constructed in accordance with the invention and showing said assembly in a normal or unset position;

FIGURE 2 is a similar view with the packer assembly in its set position within the Well bore;

FIGURES 3 and 4 are horizontal cross-sectional views taken on the lines 3-3 and 4-4, respectively, of FIG- URE 1;

FIGURE 5 is a horizontal cross-sectional view taken on the line 5-5 of FIGURE 1 and showing the frictional gripping unit which is employed in the packer assembly, with said unit in a normal or nongripping position;

FIGURE 6 is a view similar to FIGURE 5 with the gripping members of said gripping unit in a position engaging the wall of the well pipe;

FIGURE 7 is a view partly in section and partly in elevation illustrating the packer being lowered into the well bore in a reversed position when said packer is being employed as a tension type packer; and

FIGURE 8 is a view similar to FIGURE 7 with the packer assembly in its set position.

In the drawings (FIGURES 1 and 2) the numeral 10 designates a tubular mandrel or support having an axial 3,128,826 Patented Apr. 14, 1964 "Ice bore 10a and forming the main supporting element of the packer assembly. The mandrel is connected in a well tubing string T in the usual manner by an upper coupling 11 and a lower coupling 11a. The mandrel or support extends entirely through the well packer assembly and an annular flexible packing element or sleeve 12 surrounds the upper end thereof with the upper end of said pack-ing element being confined by an annular confining abutment or collar 13. The abutment or collar is supported against downward movement with respect to the mandrel It} by the engagement of an internal shoulder 13a formed within said collar with an external supporting ring or shoulder 14 on the mandrel. A plurality of segmental holddown slip members 15, having external gripping teeth 15a, have their major portions embedded, preferably by molding, within the upper exterior surface of the packing element. The upper end of each slip member has an inwardly directed guide lug 15b which engages with a complementary groove in the retaining collar 13. When the packing element is deformed into sealing engagement with the well pipe or casing C, as will be hereinafter explained, the segmental slip members move radially outwardly to engage their gripping teeth 15a with the casing wall. With the packing element in its normal undistorted position as shown in FIGURE 1, the holddown slip members are in a retracted or nongripping position.

The lower end of the sleeve-like packing element 12 is secured to and confined by a lower abutment or retaining collar 16 which surrounds the mandrel 10 and said collar is normally supported upon a supporting ring 17 secured to the external surface of the mandrel. The ring 17 forms an external projection or shoulder which limits the downward movement of the lower retaining collar and, therefore, of the packing element with respect to the mandrel. The integral annular flange 16a depends from the retaining collar 16 and encircles the upper end of an annular expander cone 18, being secured to the upper portion of said cone by suitable screws 19. The expander cone 18 is provided with a bore 18a and a counterbore 1 8b, thereby forming an internal shoulder 18c at the intersection of said bore and counter bore. The bore 18a is of a diameter to slidably engage the exterior of the mandrel while the counterbore 18b has a diameter to fit the exterior of the supporting ring 17, whereby said ring is, in eiiect, movable within the counterbore. A relatively strong coil spring 20 is confined in the counterbore 181) between the shoulder 18c and the underside of the supporting ring 17 and exerts its pressure to constantly urge the cone 18 in a downward direction with respect to the mandrel. Since the expander is connected to the lower end of the packing element through the retaining collar 16, the spring functions to constantly urge the packing element toward an extended position in which position said element is retracted or in nonsealing engagement with the casing, as illustrated in FIGURE 1.

The expander cone 18 is adapted to co-act in the usual well-known manner with gripping slips 21, said cone being formed with expanding surfaces 18d which co-act with the inclined inner surfaces 23a of the slips 21. The expander cone and the slips 21 comprise an anchoring means for the packer assembly. Each slip 21 has a T-shaped connecting lug 22 on its lower end, which lug is engageable with a complementary recess 22a provided in the upper end of a gripping unit generally indicated by the letter A. The particular gripping unit is employed in place of the usual well-known friction springs and may be of the type shown in my co-pending application, Serial No. 769,189, filed October 23, 1958. I

The gripping unit A comprises a tubular sleeve 23 which surrounds the lower portion of the mandrel 10 and which is adapted to be connected to said mandrel through the usual J-slot 24 in the sleeve and a connecting pin 25 which extends radially outwardly from the mandrel. The J-slot has a vertical portion 2411 having its upper end communicating with an inclined portion, at the base of which a pin-receiving recess 24:: is formed. The tubular sleeve 23 has an outwardly directed, integral flange portion 23a at its upper end and the T-shaped recesses 22a which receive the slip lugs 22 are disposed in this flange portion, whereby the gripping slips 21 are connected to the upper end of the gripping unit A. An annular base ring 23b is mounted on the sleeve 23 and is spaced from the enlarged upper flange portion 23a of said sleeve to provide an area for the mounting of gripping elements S of said gripping unit A.

As shown in FIGURES and 6, each gripping element S is in the form of a generally semicircular or arcuate shoe which substantially encircles one-half of the tubular sleeve 23. The lower end of each shoe has a depending extension 26 (FIGURE 1) which co-acts with an upstanding projection 27 on the flange 2322 while the upper end of each shoe has an upward extension 28 co-acting with a depending projection 29 formed on the enlarged upper portion 23a of the sleeve 23. The coaction between the extensions and projections limits the outward movement of each shoe with respect to the tubular sleeve.

Each arcuate shoe has an enlarged contact section 30 and the central outer surface 36a of this section is substantially smooth to engage the wall of the well casing C when the shoe is in non-gripping position. Gripping teeth 30b and 300 are formed on each side of the smooth surface 30a as is clearly shown in FIGURES 5 and 6. The shoes S are positioned around the sleeve 23 within the space between the enlarged upper portion 23a and the base ring 23b and are urged outwardly under the influence of coil springs 31 so that their respective smooth surfaces 30:: engage the wall of the Well casing. The ends of the springs 31 are confined within suitable recesses 32 provided in the free ends of the shoes S and said springs 31 are relatively weak, being only sufficient to urge the smooth areas of the shoes into contact with the wall of the pipe with a relatively light friction. This frictional force need be only sufiicient to prevent the shoe elements from rotating, whereby the assembly may be lowered downwardly through the well casing without presenting any great resistance to such movement.

For the purpose of increasing the engagement of each shoe S with the wall of the casing in order to assure that the gripping slips 21 secured thereto Will be held against movement when the assembly is to be set, each gripping shoe S has the internal surface of its enlarged portion 30 inclined in the manner indicated at 33 and 34. These inclined surfaces are adapted to co-act with a cam type projection 35 which is formed on the external surface of the sleeve 23. As clearly shown in FIGURE 5, two diametrically opposed projections 35 are provided and these projections are normally located as shown in this figure with respect to the inclined surfaces 36 and 37 of the arcuate shoes.

Upon a rotation of the sleeve 23 and its projections 35 with respect to the shoes S, the projections 35, co-acting with one or the

other surfaces

33 or 34 of each shoe, will result in imparting a rocking motion to the shoes in the manner illustrated in FIGURE 6. Such movement of each of the shoes results in the engagement of the gripping teeth Stib or 360 of each shoe with the wall of the casing to firmly lock the gripping unit A against rotation or other movement within the well casing. Since the gripping slips 21 are carried by and connected to the unit, an anchoring of this unit within the pipe will result in supporting the gripping slips 21 of the packer assembly against movement in the pipe. As will be explained, locking of the gripping slips 21 against movement within the casing will permit the expander cone 18 to be moved downwardly relative thereto whereby said gripping slips may be moved into gripping or anchoring position to prevent further downward movement of the cone and, therefore, of the packing element.

In the operation of the packer assembly shown in FIGURES 1 and 2 wherein the packing element is set by imposing the weight of the tubing string thereon, the parts are in the position shown in FIGURE 1 as the device is lowered within the well casing. In this position, the gripping unit A has its gripping shoes S in the position of FIGURE 5 with only the smooth portion or surface 30a of each shoe riding lightly upon the inner wall of the casing; the mandrel 10 is connected to the sleeve 23 of the gripping unit A through the pin 25 engaging within the recess 24a of the J-slot 24 and this connection maintains the slips 21 in an unset position on the mandrel.

At this time, packing element 12 is in its relaxed or retracted position and the slip expander cone 18 is raised with respect to the gripping slips. The relatively strong spring 20, which is confined between the shoulder 18c of the expander cone and the underside of the support ring 17, is exerting its pressure to hold the retaining collar 16 in contact with the support ring whereby the packer element 12 is maintained in its retracted position during lowering. Any tendency of said packing element to move into a sealing position by reason of fluid pressure acting upwardly against the lower end of said element during lowering is overcome and eliminated by the provision of the spring 20.

When the position at which the packer assembly is to be set within the well pipe is reached, the tubing T by which the assembly is lowered is rotated in a direction to the right. The first action is a rotation of the sleeve 23 of the gripping unit since the pin 25 on the mandrel is engaged in the recess 24a of the J-slot. As the sleeve 23 is rotated, its projections 35 immediately co-act with the surfaces 34 of the gripping shoes S and move said shoes into the gripping position of FIGURE 6. This anchors the gripping unit A firmly within the well casing and also locks the gripping slips 21 against any move ment therein.

Thereafter, a slight upward movement and continued rotation of the mandrel 10 moves the connecting pin 25' into alignment with the inclined portion of the J-slot an the pin will thus be guided into alignment with the vertical portion 24b of the J-slot; thereafter, the mandrel and tubing may be lowered with respect to the unit A and gripping slips 21. Such lowering moves the expander cone 18 downwardly between the main gripping slips 21 to set said slips and the subsequent application of the weight of the tubing string upon the upper end of the packing element 12 moves the parts to the position of FIGURE 2 with the packing element being deformed into sealing position with the wall of the well casing. This action is permitted since the coil spring 20 may be compressed after further downward movement of the expander cone is arrested by gripping slips 21.

At the same time that the packing sleeve 12 is deformed outwardly, the holddown gripping elements 15 on the upper portion of the packing element are moved radially outwardly into engagement with the wall of the casing. Thus, the packer assembly anchoring means consisting of slips 21 and expander cone 13 is set and the flexible packing element 12 is moved into sealing engagement with the wall of the casing. Downward movement of the entire packer assembly is prevented by the slips 21 whileany upward movement of the packing element 12 is prevented by the holddown gripping elements 15; it is noted that the gripping teeth 15a of the holddown members are disposed to lock against upward movement. The members 15 provide a simple and inexpensive holddown means for locking the assembly against upward movement.

When the packer assembly is in set position, pressure in the annulus above the packing element will act downwardly on the sealing element and then downwardly upon the expander to set the lower slips 21 into tighter gripping engagement. To set the holddown gripping members 15 into tighter gripping engagement in the event pressure below the packing element is greater than that above, radial ports 40 are provided in the lower retaining collar 16 and establish communication between the area below the assembly and the entire lower surface of the element 12. Thus pressure from below may act upwardly against the underside of the packing element 12 to urge the packing element into tighter sealing engagement and to also urge the holddown slips 15 into tighter gripping engagement with the casing to thereby prevent upward displacement of the assembly within the casing. It is noted that when the packer is in set position, the heavy coil spring is under compression and is held so by the weight of the tubing string.

In order to release and remove the packer, it is only necessary to move the well tubing T and mandrel upwardly. Such upward movement being permitted by movement of the connecting pin 25 upwardly in the vertical portion 24b of the J-slot. As the tubing is lifted, the weight of said tubing is removed from the upper end of the packing element and the force holding said packing element in its deformed position is relieved. The heavy coil spring 20 will assist in moving the mandrel upwardly because its lower end is acting on the shoulder 18c within the expander and, therefore, the energy and force of said spring is in an upward direction against the supporting ring 17. As the mandrel is raised, the connecting pin 23, co-acting with the inclined wall of the J-slot 24, moves the pin into contact with the straight wall of said slot above the recess 24a and subsequent rotation of the tubing to the left will release the gripping unit A. When the parts return to the position of FIGURE 1, the ring 17 has effected raising of the cone 18 from between the gripping slips 21 and the entire assembly may be removed from the well merely by lifting the tubing to the surface; during this removal, the coil spring maintains the packing element in its retracted position.

From the foregoing it will be seen that the coil spring 20 co-acts with the packing element 12 and expander cone 18 in a manner to prevent a premature movement of the packing element into its set position. Also, during release, the coil spring is acting in a direction tending to move the mandrel upwardly relative to the set packing element so that said spring assists rather than resists release of the assembly. The provision of the ports 40 in the lower retaining collar 16 is of importance in that pressures from below the packing element may act through said ports and against the entire underside of said element. Whenever pressure below the set packing element exceeds that above said element, the pressure acting against the entire lower surface of the packing element exerts a force which assures that deformation of the element is maintained to thereby assure firm gripping engagement of the holddown members with the casing C. In effect, the pressure below the packing element 12 thus urges the holddown members 15 into tighter griping engagement.

As has been noted, FIGURES 1 and 2 illustrate the packer assembly employed as a weight-set packer. In such packers the weight of the tubing string is imposed upon the upper end of the packing element 12 to deform the same into its sealing position with the casing. In FIGURES 7 and 8 the assembly is illustrated as being used as a tension-set packer. In this case an upward tension on the tubing string is employed to apply endwise force to the packing element 12 and such tension is utilized to maintain the packer in position.

To employ the assembly as a tension-set packer, it is only necessary to invert the packer from the position of FIGURE 1 and to lower it in its inverted position. Referring to FIGURE 7, the gripping unit A is disposed at the upper end of the assembly with the packing element 12 at the lower end thereof. During lowering, the parts are in the position shown in FIGURE 7 with the connecting pin 25 of mandrel 16 disposed within the recess 24a of the J-slot 24. At this time the packing element is in a released or retracted position and the gripping slips are raised relative to the expander cone 21. The heavy coil spring 24 confined between shoulder 18c and the supporting ring 17 is acting to hold the retaining collar 16 against said supporting ring.

When the assembly of FIGURE 7 reaches the position at which it is to be set, a left-hand torque is applied to the tubing string and such torque results in a rotation of the sleeve 23 and its projections 35 with respect to the gripping shoes; rotation of the sleeve is caused by the engagement of the pin 25 with the short recess 24a of the J-slot. As explained, the gripping shoes S engage the wall of the casing to lock the gripping slips 21 of the packer anchoring means against movement within the pipe.

Thereafter, the tubing string 19 is lowered sufiiciently to cause pin 25 to clear the recess 24a and to move said pin into alignment with the inclined portion of the J-slot. Raising of the tubing will cause pin 25 to align with vertical portion 24b. The tubing is then raised and placed under the desired setting tension, the raising of the tubing effecting an upward movement of the expander cone to expand the slips 21, followed by deformation of the packing element 12 into sealing engagement with the casing. The torque in the tubing string is then preferably released but the desired tension is maintained to hold the assembly in set position as shown in FIGURE 8.

To release the assembly from the position of FIGURE 8, the tubing string is first lowered to relieve the tension on the packer and is then place under a right-hand torque. Further lowering of the tubing results in relieving the endwise force applied to the packing element 12 and the release is assisted by the action of the spring 20 as has been heretofore described. When the connecting pin 25 is returned into the recess 24a, the various parts have returned to their original position as shown in FIGURE 7 and thereafter removal of the assembly by the tubing string may be carried out.

As in the first form of the invention, the heavy coil spring is employed to prevent premature setting of the packing element and to assist in release thereof. The provision of the communicating ports 4t in the retainer ring assure that the packing element and its holddown member 15 will be maintained in set position by the pressure differential across the packing element.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims Without departing from the spirit of the invention.

What I claim is:

l. A well packer assembly including, a tubular sup port, an annular flexible packing element mounted on the. support, an external abutment on the support engaging with one end of the packing element to confine said element against movement in one direction on the support, an anchoring means for anchoring the assembly against movement in one direction in a well bore carried by the support including an expander cone and slips, said packing element engaging one of said expander cone and said slips and confining that end of the packing element which is opposite the end engaged by said abutment, shoulder means on said tubular support and said expander cone, a spring means engaging said shoulder means on said tubular support and said expander cone urging said expander cone in a direction permitting movement of said packing element towards retracted or non-sealing position, and means mounting said anchoring means on the support for limited longitudinal movement relative to said support, whereby said support may be moved with respect to the anchoring means after the latter has been ahchored within the well bore to thereby apply end- Wire force to the packing element to deform the same into sealing position.

2. A well packer assembly as set forth in claim 1, together with segmental holddown members embedded in the upper outer peripheral portion of the packing element and movable radially outwardly into gripping engagement with the wall of the well bore when said element is deformed into sealing position.

3. A well packer assembly as set forth in claim 1, together with means for conducting the pressure which is present within the well bore and surrounding the anchoring means against the entire cross-sectional area of the packing element to urge said element into tighter sealing engagement.

4. A well packer assembly as set forth in claim 1, together with segmental holddown members embedded in the upper outer peripheral portion of the packing element and movable radially outwardly into gripping engagement with the wall of the well bore when said element is deformed into sealing position, and means for conducting the pressure which is present in the well bore surrounding the anchoring means against the entire crosssectional area of the packing element to urge said element and its holddown members into tighter engagement with the wall of the well bore.

5. A well package assembly including, a tubular support, an annular flexible packing element mounted on the support and deformable into sealing position with the Wall of the Well bore, an external abutment on the support engaging one of the packing element to confine said element against movement in one direction on the support, an anchoring means for anchoring the assembly against movement in one direction within a well bore and comprising an expander cone surrounding the support adjacent that end of the packing element opposite said abutment and gripping slips slidable relative to said cone, means for connecting the expander cone to that end of the packing element which is opposite the end engaged by the abutment, and spring means surrounding the support and co-acting with said support and expander cone and constantly urging said expander cone in a direction which will maintain the packing element attached to said cone in a rectracted or non-sealing position.

6. A well packer assembly including a tubular support, an annular flexible packing element mounted on the support and deformable into sealing position with the wall of the Well bore, an external abutment on the support engaging one end of the packing element to confine said element against movement in one direction on the support, an anchoring means for anchoring the assembly against movement in one direction within a well bore and comprising an expander cone surrounding the support adjacent that end of the packing element opposite said abutment and gripping slips slideable relative to said cone, means for connecting the expander cone to that end of the packing element which is opposite the end engaged by the abutment, an external projection on said support engageable by that end of the packing element which is, opposite the abutment when said packing element is in retracted position, and a coiled spring surrounding the support and confined between said external projection on the support and the expander cone and exerting its force to constantly urge said cone and the packing element attached thereto in a direction maintaining the packing element engaged with said shoulder whereby the packing element is constantly urged toward its retracted position.

7. A well packer assembly as set forth in claim 5, together with means for conducting the pressure which is present in the Well bore and surrounding the anchoring means against the entire cross-sectional area of the packing element when said element is in its sealing position to urge said element into tighter sealing engagement with the wall of the well bore.

8. A well packer assembly as set forth in claim 5, together with segmental holddown members embedded in the upper outer peripheral portion of said packing element and movable radially outwardly into gripping engagement with the Wall of the well bore when said element is deformed into sealing position.

9. A well packer assembly as set forth in claim 5, wherein the anchoring means also includes a gripping unit connected with the gripping slips, said unit comprising a sleeve slideably surrounding the support, arcuate gripping shoes mounted on the sleeve, and cam-surfaces between the sleeve and shoes adapted to move the shoes into gripping engagement with the wall of the Well bore upon relative rotation of the sleeve and shoes, and a connection between the support and sleeve whereby rotation may be imparted to the sleeve to actuate said shoes and thereby hold the gripping slips stationary to allow movement of the expander cone with respect to the slips to set the latter.

10. A well packer assembly as set forth in claim 6, wherein the anchoring means also includes a gripping unit connected with the gripping slips, said unit comprising a sleeve slideably surrounding the support, arcuate gripping shoes mounted on the sleeve, and cam-surfaces between the sleeve and shoes adapted to move the shoes into gripping engagement with the wall of the well bore upon relative rotation of the sleeve and shoes, and a connection between the support and sleeve whereby rotation may be imparted to the sleeve to actuate said shoes and thereby hold the gripping slips stationary to allow movement of the expander cone with respect to the slips to set the latter.

References Cited in the file of this patent UNITED STATES PATENTS 1,772,682 Phipps Aug. 12, 1930 2,590,502 Brown Mar. 25, 1952 2,639,773 Webber May 26, 1953 2,652,894 Brown et al Sept. 22, 1953

Claims

1. A WELL PACKER ASSEMBLY INCLUDING, A TUBULAR SUPPORT, AN ANNULAR FLEXIBLE PACKING ELEMENT MOUNTED ON THE SUPPORT, AN EXTERNAL ABUTMENT ON THE SUPPORT ENGAGING WITH ONE END OF THE PACKING ELEMENT TO CONFINE SAID ELEMENT AGAINST MOVEMENT IN ONE DIRECTION ON THE SUPPORT, AN ANCHORING MEANS FOR ANCHORING THE ASSEMBLY AGAINST MOVEMENT IN ONE DIRECTION IN A WELL BORE CARRIED BY THE SUPPORT INCLUDING AN EXPANDER CONE AND SLIPS, SAID PACKING ELEMENT ENGAGING ONE OF SAID EXPANDER CONE AND SAID SLIPS AND CONFINING THAT END OF THE PACKING ELEMENT WHICH IS OPPOSITE THE END ENGAGED BY SAID ABUTMENT, SHOULDER MEANS ON SAID TUBULAR SUPPORT AND SAID EXPANDER CONE, A SPRING MEANS ENGAGING SAID SHOULDER MEANS ON SAID TUBULAR SUPPORT AND SAID EXPANDER CONE URGING SAID EXPANDER CONE IN A DIRECTION PERMITTING MOVEMENT OF SAID PACKING ELEMENT TOWARDS RETRACTED OR NON-SEALING POSITION, AND MEANS MOUNTING SAID ANCHORING MEANS ON THE SUPPORT FOR LIMITED LONGITUDINAL MOVEMENT RELATIVE TO SAID SUPPORT, WHEREBY SAID SUPPORT MAY BE MOVED WITH RESPECT TO THE ANCHORING MEANS AFTER THE LATTER HAS BEEN ANCHORED WITHIN THE WELL BORE TO THEREBY APPLY ENDWISE FORCE TO THE PACKING ELEMENT TO DEFORM THE SAME INTO SEALING POSITION.