Heat Actuated Well Packer

Abstract

A heat operated well packer in which a closed pressure chamber includes a fluid that expands on the application of heat for providing the motive force for setting the packer. A well packer having a packing seal and slips which are actuated by a piston in which a closed pressure chamber having a nonexplosive fluid which expands upon the application of heat is in fluid communication with the piston, and heating means applies heat to the closed chamber for moving the piston and setting the packer. A setting tool releasably engaging the packer and including a second closed pressure chamber having a fluid which expands upon the application of heat for actuating a second piston for releasing the setting tool from the packer when heat is applied to the second pressure chamber.

Description

BACKGROUND OF THE INVENTION

Gas and/or oil well packers using electric conductor lines which actuate an explosive powder to move pistons that set the packer slips and seals and separated the setting tool from the packer have been used in the past.

The present invention is directed to an improved packer which is set by heat in which the setting force may be controlled by the amount of heat applied to a fluid that expands upon the application of heat and provides increasing pressure which may be used to move a piston that sets the packer slips and seal.

SUMMARY

The present invention is directed to a well packer adapted to be set in a conduit in a well bore and which includes an initially retracted packing seal and slips which are actuated by piston means in which a closed pressure chamber containing a fluid that expands upon the application of heat is provided in the packer or the setting tool. Heating means apply heat to the closed chamber for increasing the pressure of the fluid for moving the piston means and setting the packer.

A still further object of the present invention is the provision of a heat operated well packer in which a closed pressure chamber of fluid is positioned in the packer and the heating means is positioned in a releasable setting tool.

A still further object of the present invention is the provision of a heat actuated well packer in which a heat expandable liquid in a closed pressure chamber is heated by an electrical heating coil through an electrical conductor to the surface for controlling the pressure of the fluid thereby controlling the force setting the well packer.

A still further object is the provision of a setting tool including a heat expandable liquid in a closed pressure chamber and heating means carried by the setting tool for increasing the pressure of the fluid to rupture the closed chamber and provide the force for setting the well packer.

Yet a still further object of the present invention is the provision of a setting tool releasably connected to the packer with a second piston which releases the connection between the setting tool and the packer when the second piston is actuated. A second closed pressure chamber is provided in communication with the second piston with second heating means applying heat to the second chamber for moving the second piston and releasing the setting tool from the packer.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a fragmentary elevational view of one embodiment of the present invention with the well packer shown in the retracted position,

FIG. 2 is a view similar to FIG. 1 showing the well packer in the set position,

FIG. 3 is a view similar to FIG. 2 with the well packer in the set position and the setting tool released from the packer,

FIG. 4 is an electrical schematic of the embodiments of FIGS. 1-3,

FIG. 5 is a fragmentary elevational view of another form of the present invention with the packer shown in the retracted position, and

FIG. 6 is a view similar to that of FIG. 5 with the packer shown in the set position.

DESCRIPTION OF THE PREFERRED EMBODIMENT

While the present invention may be utilized with any type of well packer in which piston means is moved to set the packer slips and packer seal, the present invention will be described, for purposes of illustration only, as used in a Camco type HSP-1 packer.

Referring now to the drawings, the packer of the present invention is generally indicated by the reference numeral 10, and is shown being lowered into position by a setting tool generally indicated by the reference numeral 12 in a conduit such as a casing 14 in a well bore.

The packer 10 includes the usual packer seal means generally indicated by the reference numeral 16, an upper set of slips 18 and a lower set of slips 20, all of which are shown in their retracted positions in FIG. 1. The packer 10 also includes a mandrel 22, and a cylinder 24 and piston 26 which when moved apart by pressure will set the slips 18 and 20 and the packer seal means 16.

A lower slip cone 28 is connected to a ratchet sleeve 30. Thus as the piston 26 is actuated and forced downwardly, the sleeve 30 will move the cone 28 toward the lower slips 20 forcing them outward and into engagement with the conduit 14. The top end of the cylinder 24 is abutting the lower end of the packing seal means 16 and when the cylinder 24 is moved upwardly the sealing means 16 will be compressed and upper cones 32 will move upper slips 18 outwardly into engagement with the well casing 14 and sealing means 16 will engage the casing 14 to provide the desired seal. Packer 10 is shown in the set postiion in FIG. 2.

Initially, the cylinder 24 and piston 26 are held in a retracted position by one or more shear pins 34. However, when the pressure in the cylinder 24 is sufficient, the shear pins 34 will be sheared allowing relative movement between the cylinder 24 and piston 26. A ratchet 36 is provided between the cylinder 24 and the ratchet sleeve 19 allowing upward movement of the cylinder 24 relative to the piston 26 when pressure is applied to the cylinder 24 and piston 26, but prevents reverse movement of the cylinder 24 relative to the piston 26 thereby locking the slips 18 and 20 and the packer seal 16 in the expanded position when the packer is set. The above described packer is generally conventional.

The present invention is directed to providing an improvement in the means for actuating the piston and setting the packer by providing a fluid that expands upon the application of heat and preferably vaporizes at a selected temperature, and results in increasing pressure which is used to set the packer. Thus, the temperature of the fluid can be controlled thereby controlling the pressure of the fluid and the setting force applied to the packer. A closed pressure chamber is provided such as chamber 40 in the packer in the cylinder 24 for applying pressure to the cylinder 24 and the piston 26 for actuating and setting the packer when heat is applied to the chamber 40. The chamber 40 is sealed with a fluid, either liquid or gas, which expands or vaporizes as the temperature of the chamber 40 is increased. While any suitable fluid such as various hydrocarbons or carbon tetrachloride may be used, refrigerants such as halogenated carbons such as sold under the trademark Freon are preferred because of their higher pressures upon vaporization, their nonexplosive nature, and availability.

Any suitable heating means may be used to apply heat to the closed pressure chamber 40 such as an electrical heating coil 42 which is preferably positioned in the setting tool 12, one end of which may be grounded to the casing 14 and the second end connected to a conductor 44 (FIG. 4) for connection to a source of controlled electric power 45 at the surface. Thus, the voltage applied to the coil 42 may be suitable controlled by any desired means to supply the heat from the coil 42 to the chamber 40 for creating the desired pressure for setting the packer 10. For example, assuming that the temperature of the well at the place it is desired to set the packer is 200.degree. F. which causes a liquid-vapor pressure of 4,000 psi in the chamber 40, the shear pin or pins 34 may be set to be sheared at a 5,000 psi internal pressure of the chamber 40. By the application of additional heat from the heating coil 42 to the chamber 40, the internal pressure in the chamber 40 may be increased to cause the pins 34 to shear and allow the packer to set. As best shown in FIG. 2, the heat from the heating coil 42 has expanded the fluid in the chamber 40 shearing the shear pins 34 and moving cylinder 24 and piston 26 away from each other setting the upper and lower slips 18 and 20 and setting the sealing means 16. The ratchet 36 holds the cylinder 24 and piston 26 in the expanded position thus holding the slips and packer seal in the set position.

After the packer 10 is set, the setting tool 12 may be released from the set packer 10. However, in the event the packer should develop a leak about the packer seal 16, packer 10 can be additionally and further reset by replacing the setting tool 12 in the packer 10 and again selectively energizing the heating coil 42 and heating chamber 40 to further move the cylinder 24 and piston 26 away from each other to further expand the slips 18 and 20 and/or the packer seal means 16.

While the setting tool may be conventionally connected to and disconnected from the packer 10, a second fluid expansion chamber may be provided and heated to actuate a mechanism for causing the setting tool to be separated from the packer. Thus, referring to the drawings, releasable connecting means may be provided between the setting tool 12 and the packer 10 such as a shear pin or pins 46. A piston 48 is provided in the setting tool 12 along with a closed pressure chamber 50 having a nonexplosive fluid which expands upon the application of heat similar to that in chamber 40. Heating means for applying heat to the heating chamber 50 such as heating coil 52 is positioned adjacent chamber 50. Thus, after the packer 10 is set, the setting tool 12 may be released from the packer 10 by applying electricity to the heating coil 52 thereby heating the fluid in chamber 50 which expands and increases the pressure against the piston 48 for shearing the pins 46.

As best seen in FIG. 4, a single electrical conductor 44 may be provided connected to a source of dc power for selectively actuating the electric coils 42 and 52 by incorporating diodes 54 and 56 in the conducting paths to the coils 42 and 52, respectively. Thus, by actuating reversing switch 58 in one direction the current will pass through diode 54 for supplying voltage to the coil 42 and on reversing the switch 58 electrical power will be supplied through the single line conductor 44 through diode 56 for energizing coil 52.

Thus, as best seen in FIG. 3, the piston 48 has moved upwardly shearing the pin 46 releasing the setting tool 12 from the packer 10 whereby the tool 12 may be conventionally removed such as on a wireline (not shown).

Of course, other modifications may be utilized, one of which is shown in FIGS. 5 and 6 where like parts are identified by corresponding numbers of FIGS. 1-4 with the addition of the suffix "a." In FIGS. 5 and 6 the closed pressure chamber is positioned in the setting tool 12a instead of the packer 10a. Thus, the chamber 60 in the cylinder 24a is exposed to the piston 26a but is open through a port 62 to the interior of the mandrel 22a. A closed pressure chamber 64 is provided in the setting tool and includes a nonexplosive fluid which expands upon the application of heat and further includes a frangible portion 66 preferably adjacent the port 62 which will rupture upon increase of the pressure in the chamber 64 to a predetermined level. Seals 68 and 70 are provided between the setting tool 10a and the mandrel 22a to insure that when the fluid in the chamber 64 expands and ruptures the disc 66, that the fluid pressure will flow through ports 62 into chamber 60 and set the packer 10a by acting against the cylinder 24a and the piston 26a, as best seen in FIG. 6. Heating coil 72 is provided in the setting tool 12 adjacent the closed chamber 64 to apply heat to the chamber 64 and raise the pressure to the desired level for setting the packer 10.

The present invention therefore, is well adapted to carry out the objects and attain the ends and advantages mentioned, as well as others inherent therein. While presently preferred embodiments of the invention are given for the purpose of disclosure, numerous changes in the details of construction and arrangement of parts will readily suggest themselves to those skilled in the art and are encompassed within the spirit of the invention and the scope of the appended claims.

Claims

What is claimed is:

1. In a well packer adapted to be set in a conduit disposed in a well bore having a mandrel, an initially retracted packing seal means, initially retracted slip means surrounding said mandrel, piston means for expanding the slip means and the packing seal means into engagement with the conduit, the improvement in means for actuating said piston means comprising,

a closed pressure chamber adapted to be in fluid communication with the piston means,

said chamber including a nonexplosive fluid which expands upon the application of heat, and

heating means for applying heat to the closed chamber for moving the piston means and setting the packer.

2. The apparatus of claim 1 wherein the fluid is a halogenated hydrocarbon.

3. The apparatus of claim 1 wherein the heating means is an electrical heating coil.

4. The apparatus of claim 1 wherein the closed pressure chamber is positioned in the packer and the heating means is positioned in a setting tool releasably connected to the packer.

5. In a well packer adapted to be set in a conduit disposed in a well bore having a mandrel, an initially retracted packing seal means, initially retracted slip means surrounding said mandrel, and piston and cylinder means for expanding the slip means and the packing seal means into engagement with the conduit, the improvement in means for actuating said piston and cylinder means comprising,

said cylinder being a closed pressure chamber in the packer and including a nonexplosive fluid which expands upon the application of heat,

a setting tool releasably connected to the packer, and

electrical heating means carried by the setting tool and positioned adjacent the closed pressure chamber when the setting tool is connected to the packer.

6. The apparatus of claim 5 including,

means releasably connecting the setting tool to the packer,

second piston means for actuating the releasable connecting means when the piston is actuated,

a second closed pressure chamber in fluid communication with the second piston means and including a nonexplosive fluid which expands upon the application of heat, and

second heating means for applying heat to the second closed chamber for moving the second piston means and releasing the setting tool from the packer.

7. The apparatus of claim 6 wherein the releasable connecting means are shear means.

8. In a well packer adapted to be set in a conduit disposed in a well bore having a mandrel, an initially retracted packing seal means, initially retracted slip means surrounding said mandrel, and piston means for expanding the slip means and the packing seal means into engagement with the conduit, the improvement in means for actuating said piston means comprising,

a setting tool engaging the packer,

a closed pressure chamber carried by the setting tool and including a nonexplosive fluid which expands upon the application of heat, said closed pressure chamber including a fragible portion exposed to the piston means,

seal means between the packer and the setting tool on opposite sides of the fragible portion, and

heating means carried by the setting tool for applying heat to the closed chamber for increasing the pressure therein for rupturing the fragible portion and applying pressure to the piston means and setting the packer.

9. The apparatus of claim 8 including,

means releasably connecting the setting tool to the packer,

second piston means for actuating the releasable connecting means when the piston is actuated,

a second closed pressure chamber in fluid communication with the second piston means and including a nonexplosive fluid which expands upon the application of heat, and

second heating means for applying heat to the second closed chamber for moving the second piston means and releasing the setting tool from the packer.