US2187481A - Well packer - Google Patents

Description

Jan. 16, 1940. R. c. BAKER ET AL 2,187,481

WELL PACKER Filed Dec. 12, 1938 INVENTOR. REueE/v C. BA KER LARENCE E.BURT' BY AT'TORNEY mite lam. 1e,

, Reuben 0. Baker, Coalinga, and iDlarence E. Burtlms Angeles, @alit" assignors to Baker poration of California Oil 'lools, l[nc., Huntington llark, @alit" a cor- Application December 12, 1938, Serial No. 24L5,239

'7 claims. (on; ice-i2) This invention relates to that general type of well devices commonlyknown as well packers, which have particular utility in oil well practice for packing off a well at any selected point.

It is-the principal object of the present invention to provide an improved device 'of the character referred to which may be detachably connected to the lower end of astring of tubing or the like and be safely and properly run-in and set at any desired point in'a well casing in such manner as to resist dislodgement by pressures to whichit may be subjected, and particularly to provide a packer of the cup packing type having a packing protecting means nor mally restraining the packing cup against expansion and protecting said cup against unde-' sirable wear during a run-in of the device, and in which'the setting of the device is under control of an operator at the derrick floor; the device providing a packer adaptable for use in various situationsrequiring a set or anchored packer and being particularly adaptable for use as a bridge plug in any situation in'which it is necessary or desirable to bridge a well casing.

In general, the packer comprises a tubular packing device adapted to be run-ina well casing at the lower end of a string of tubing or drill pipe by which it may be manipulated by an openator at the derrick floor, and it includes in its 30' structure operable slips for anchoring it firmly in the surrounding casing at a desired location and an expansible packing means or sealing element for sealing ofi the annular space between the run-in string, of which it is a part, and the wall of the casing, the slips and the packing element being ,operable'by fluid pressure and by manipulation of the run-in string.

The packing element with which the device is provided isan inherently expansive cup packing and for the purpose of preventing undesirable wear thereof and to insure its safe and proper passage down a well-casing, the device is provided with means for normally protecting and for maintaining said packing cup contracted dur- 45 ing the'running-in of the device and arranged to be later released by fluid pressure for engagement with the casing wall.

As this device can be set at any desired point in a well casing to form a bridge therein, it will 50 be particularly adaptable for use in cementing operations, in which use the run-in string will be disconnected from the set device which will later be drilled up in a subsequent drilling operation, the device, for this reason, being constructed of readily drillable materials.

The invention is exemplified in the following description and illustrated byway of example in the accompanying drawing, in which: I

Fig. l is a longitudinal section through'a portion of a well casing and showing therein one form of embodiment of our improved packing device, with the partsthereof in the positions they assume when the packer is being run-in the casing.

Fig. 2 is-a similar view, the packer being shown it) partly in elevation, illustrating a tripped condition with the packing cup engaging the casing wall and'the slipsin gripping engagement there'- with.

In Fig. 1, A designates the packing device in its 15 normal condition as it is run-in the well casing B, it being noted that the device is of general tubular character, cylindrical in cross-section, and of normal overall external diameter just slightly less than .the internal diameter of the 20 well casing in which it is to be run and set.

This packer includes a tubular body Ml adapted for attachment to the lower end of a run-in string of tubing or drill pipe C, and in the structure shown we prefer a means of attachment 5 which comprises a relatively coarse screwthread connection, preferably a square left-hand screw-thread so that the string 0 may be rotated in a right-hand direction to disconnect it from the setpacker without danger of disconnecting any of the usual right-hand screw-thread connections between the several lengths of tubing or pipe which comprise the relatively long run-in string.

The tubular body!!! is provided with lateral discharge ports II and below these ports said body is enlarged to provide a packing restraining means comprising an annular cup-like member I2 having a downwardly extended marginal lip l3. The body, below the member I2, is of re- 40 duced diameter and, for economy of manufacture, is formed of a length of pipe which is screwthreaded into said member I2.

Slidably mounted on the reduced lower portion of the body I0 is a slip expanding annular cone I4 and an annular resilient packing element l5 of cup form having an inner annular lip l6 and an outer annular marginal lip I1 spaced from said inner lip. Normally this packing cup I5 is positioned so that its marginal lip I1 is engaged under themarginal lip I3 of the packing restraining means l2 and is thus initially restrained against expansion.

It is desired that the cup I5 be connected to the cone M by interlocking means and to this end the lower end of said cup and the upper end of said cone are of companion contour, the cone being provided with an internal annular flange l8 defining an adjacent internal groove and the cup having an external annular bead l9 disposed in said groove and defining an adjacent external groove accommodating said bead. This packing cup is preferably formed of relatively tough rubber or of other suitable material of a nature having suiiicient resiliency to cause the outer marginal lip II, when released from restraint, to flex outwardly and engage the casing wall.

The means for anchoring the packer in set position in the well casing comprises a plurality of circularly spaced slips-20, each of which is secured to the cone I I in the inefi'ective position shown in Fig. 1, by two shear screws 2| and 22, and is provided with external horizontally disposed wickers or teeth formed to have a downward gripping engagement with the casing wall.

Within the tubular body In there is an actuating member comprising a tubular slide valve 23 which constitutes a portion of the fluid passage through the device and is normally positioned to close the several discharge ports I I. The upper end of the bore of this slide valve 23 is formed to provide a seat 24 adapted to be engaged by a tripping ball 25 which will be sent down the tubing string to close said fluid passage when the packer has reached its position of use, as will later be explained.

The actuating slide valve 23 extends to the lower end of the body I where it is connected to the lower end of the slip expanding cone I4 by screws 26 which extend through companion longitudinally elongated slots 21 formed in the body. This actuating slide valve 23, together with the cone I4, the slips 20, and the packing cup l5, are all initially releasably retained in their normal upper positions by a shear screw 28 which connects the upper end of the slide valve 23 with the body H), as shown in Fig. 1.

To the lower end of the body is secured an annular abutment member 29 which is shaped to guide the packer down the well casing and is provided with by-pass ports 30 contributing towards an easy passage of the packer down-.

wardly through such fluid as may be present in the well casing.

In practicing our invention, the packer will be constructed and assembled as shown in Fig. 1. In this condition the packing cup is restrained against expansion, the slips are disposed in collapsed condition, and the discharge ports are closed., With the packer thus'normally conditioned, it is screwed on the lower end of the run-in string of tubing 0 and lowered into the well casing B as the tubing string is made up in the usual manner.

In its use in cementing operations, the packer will be lowered to a position just below a cementing station defined by one or more lateral discharge ports formed in the casing wall or by a section of perforated casing. Circulation may then be established to clear the well of heavy mud, drilling detritus, or other undesirable substances. When the operator is satisfied that the proper condition for effective cementing has been attained, the tripping ball 25 will be dropped in the tubing string and pumped down to its seat 24 to close the fluid passage and thus block the circulation.

With the circulation thus blocked by the seating-of the ball 25, fluid pressure will be built up in the tubing line and in the packer above said ball until such fluid pressure becomes sufficient to shear the screw 28 and drive downwardly the sleeve valve 23 and its associated parts. This downward movement of the sleeve valve will first withdraw the marginal lip ll of the packing cup from under the marginal lip l3 of the packing restraining means and thus release said marginal lip I! for automatic expansion to engagement with the casing wall and will lower the slips to engage the body abutment 29 which limits their downward movement.

Continued building up of fluid pressure will shear the slip retaining screws 2| and 22 and drive the slip expanding cone I4 downwardly and wedge the several slips into gripping engagement with the casing wall to set the packer, and will open the lateral discharge ports II to reestablish the circulation above the packer, the pressure of this reestablished circulation now being exerted to further expand the released packing cup and more tightly wedge the cone [4 behind the several slips. I n

It will be obvious from the above description and from the drawing that any pressure built up in the casing above the set packer will tend to more closely press the packing against the body l0 and the casing wall and to more forcefully urge the cone l4 downwardly to cause the several slips 20 to take a deeper bite into the casing wall. Therefore, it should be evident that the packing efliciency of the device and its resistance to dislodgement will increase with any increase of down-pressure to which it is subjected. I

The device in the set condition shown in Fig. 2 is then ready for a cementing operation and cement slurry may be pumped down the tubing string C to discharge into the casing above the packer through its discharge ports ll.

After completion of the cementing operation, the device will be left anchored in the well casing and the tubing string 0 will be rotated in a right-hand direction and disconnected from the body- Ill, due to the left-hand screw-thread connection between the two, the disconnected tubing string then being pulled from the well.

In other operations not involving the use of cement, the circulation of drilling fluid may be eliminated and the device tripped by gas or other fluids under pressure.

From the foregoing it will be evident that we have provided a device which may be set in a well casing at any desired point to provide a fluid-tight seal for cementing and other operations, and which will be securely anchored in set stood 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 our invention, what we claim and desire to secure by Letters Patent is:

1. In a packing device adapted to be attached to and lowered into a well casing by a string of tubing and having a normally open fluid pasposition against dislodgement by such pressures dill dill

sage for receiving fluid pumped through said tubing and for discharging said fluid into said casing, a tubular body having a lateral discharge port, an annular packing cup slidable on said body below said discharge port and having an expansible longitudinally extended marginal lip, a packing restraining means carried by the body between said discharge port and said packing and normally surrounding and engaged over said lip to restrain it against expansion, a tubular valve means connected to said packing and normally closing said discharge port, said valve 1 means forming a portion of said fluid passage and being slidable within the bore of the body,

connecting means capable of, being released normally maintaining said valve means in closed position, anda closure adapted to be sent down the tubing string to close the bore of said tubular valve means to cause a build up of fluid pressure in said fluid passage above said closure, such pressure being effective to release said connecting means and actuate said valve means to translate said packing cup free from said lip restraining means and to subsequently open said discharge port.

2. In a device of the character disclosed, the combination of a body having an axial flow passage and adapted to be attached to the lower end of a string of tubing'and lowered into a well casing, an annular packing cup slidable on said body and having an expansible marginal lip longitudinally extended upwardly, a packing restraining means fixed on the body and normally surrounding and engaged over said lip to restrain it against expansion, and means including means adapted to be sent down said tubing string to close said flow passage operable to translate said packing cup to withdraw its marginal lip from within said lip restraining means.

3. In a device of the character disclosed, the combination of a tubular body providing an axial flow passage and adapted to "be attached to the lower end of a string of tubing and lowered into a well casing, an annular packing cup slidable on said body and having an expansible marginal lip longitudinally extended upwardly, a packing restraining means fixed on the body and normally surrounding and engaged over said lip to restrain it against expansion, and hydraulically actuated means including means adapted to be sent down said tubing string operable to close said flow passage and translate said packing cup to withdraw its marginal lip from within said lip restraining means.

4. In a device of the character disclosed, the combination of a tubular body having a lateral discharge port and adapted to be attached to the lower end of a string of tubing and lowered into a well casing, an annular packing cup slidable on said body below said discharge port and having an expansible longitudinally extended marginal lip, a packing restraining means carried by the body between said discharge port and sa d packing and normally surrounding and engaged over said lip to restrain it against expansion, and valve means normally closing said discharge port and connected with said packing cup, said valve means being operable to translate said packing cup to withdraw its marginal lip from within said lip restraining means and to subsequently open said discharge port.

5. In a device of the character disclosed, the combination of a body adapted to be attached to the lower end of a string of tubing and lowered into a well casing, a slip expanding means slidable on said body, slips associated with said expanding means, connecting means capable of being released normally connecting the slips to said expanding means in ineffective positions, an annular packing cup connected to said expanding means and having an expansible longitudinally extended marginal lip, a packing restraining means carried by the body and normally surrounding and engaged over said lip to restrain it against expansion, said body having an abutment longitudinally aligned with said slips, and means for longitudinally translating said packing, said slip expanding means and said slips to first withdraw said packing lip from said lip restraining means to permit it to expand and engage the casing wall and to engage the slips with said abutment to arrest their longitudinal travel, and to subsequently release said slip connecting means and cause the slip expanding means to expand the several slips radially into gripping engagement with the casing wall.

6. In a device of the character disclosed, the combination of a tubular body adapted to be attached to the lower end of a string of tubing and lowered into a well casing, a slip expanding means slidable on said body, slips associated with said expanding means, connecting means capable of being released normally connecting the slips to said expanding means in inefiective positions, an annular packing cup connected to said expanding means and having an expansible longitudinally extended marginal lip, a packing restraining means carried by the body and normally surrounding and engaged over said lip to restrain it against expansion, said body having an abutment longitudinally aligned with said slips, and hydraulically actuated means for longitudinally translating said packing, said slip expanding means and said slips to first withdraw said packing lip from said lip restraining means to permit it to expand and engage the casing wall and to engage the slips with said abutment to arrest their longitudinal travel, and to subsequently release said slip connecting means and cause the slip expanding means to expand the several slips radially into gripping engagement with the casing wall.

7. In a device of the character disclosed, the combination of a tubular body adapted to be attached to the lower end of a string of tubing and lowered into a well casing and to receive fluid pumped down said tubing string, said body having a longitudinal fluid passage and a lateral discharge port, a slip expanding means slidable on said body, slips associated wth said expanding means, connecting means capable of being released normally connecting the slips to said expandingmeans in ineffective positions, an annular packing cup connected to said expanding means and having an expansible longitudinally extended marginal lip, a packing restraining means carried by the body and normally surrounding and engaged over said lip to restrain it against expansion, said body having an abutment longitudinally aligned with said slips, a tubular valve slidably disposed Within the body to form a portion of said fluid passage, means connecting said valve to said slip expanding means, valve restraining means capable of being released normally holding said valve in position to close said discharge port, and a closure adapted to be sent down the tubing stringto close the bore of said valve and close said fluid passage to cause a build up of pressure in said passage above said closure, such pressure being effective to release the valve restraining means and longitudilease the slip connecting means and cause the nally translate said valve, said packing, said slip slip expanding means to expand the several slips expanding means and said slips to first withdraw radially into gripping engagement with the casthe packing lip from its restraining means and ing wall. 5 then open said discharge port and engage the REUBEN C. BAKER. 5

slips with said abutment and to subsequently-re CLARENCE E. BURT.

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