US2788856A - Plunger arrangement for closing well casing - Google Patents

Description

April 16, 1957 J. E. ORTLOFF PLUNGER ARRANGEMENT FOR CLOSING WELL CASING Filed May 25, 1955 2 Shets-Sheet 1 FIG-IA Inventor John E. Orfloff By W Attorney April 16, 1957 J. E. ORTLOFF PLUNGER ARRANGEMENT FOR CLOSING WELL CASING Filed May 25, 1955 2 Sheets-Sheet 2 FIG.'-2

Inventor United States PLUNGER ARRANGEMENT FOR CLOSING WELL CASING John E. Ortlofl'lulsa, Okla, assignor to Esso Research and Engineering Company, a corporation of Delaware Application May 25, 1955, Serial No. 510,995

7 Claims. (Cl. 166-92) casing after which a packer held by the plunger can be expanded to close the casing.

With any high pressure producing oil Well there is always the danger that the well will get out of control and that the well cannot be closed 011 with the existing equipment. Wells that have blown out as a result of easing failure caused by excessive corrosion present a serious roblem since in such cases there will usually be nothing left but the bare casing and therefore no structure such as flanges will be available to use as an anchoring means in attempting to cap the well. Wild wells of this nature present a particularly serious problem in marine installations since corrosion is particularly bad at the water line and the casing may have failed at the water level.

It is an object of the present invention to provide equipment that can be set in place above the well casing and quickly inserted into the casing to seal it ofl. In accordance with this invention, a split bracket is attached to the casing. The bracket supports a hydraulic cylinder having a piston to which is attached a plunger provided with an expansible packer. The cylinder is swung into place over the casing, the plunger is pushed by the piston into the casing and the packer is expanded preferably by hydraulic pressure. Once the blowout is stopped the well can be killed by pumping in heavy muds so that the necessary repairs can be made to the well.

The nature and objects of the invention will be more readily understood when reference is made to the accompanying drawings in which: 7

Figure 1 is an elevational view partly in section showing the lower portion of an apparatus of the invention attached to the top of a well casing;

Figure 1A is an upper continuation of the structure of Figure 1, with a portion of the structure repeated; and

Figure 2 is a schematic side elevational view showing the manner in which the apparatus is swung over the casing to insert the plunger.

Referring now particularly to the various figures it will be seen that the apparatus is provided with a split bracket 12 which iis attached to the top of the well casing 11 either by means of the flanges 13 which are clamped together by bolts or by welding the bracket to the casing. Unless the welding can be done underwater it will usually be preferable to attach the bracket by the clamping method when the bracket must be placed below the level of the water. The split bracket is provided with hinge pins 14 which rotatably receive collars 15 to which sleeves 16 are attached. The sleeves 16 are thus pivotally supported by the bracket. After the bracket has been attached to the casing the balance of the apparatus may be attached to the bracket by inserting the elongated rods 17 into the sleeves 16 and fastening them in place with the bolts 18.

The rods 17 are fastened to and support an elongated atent 2,788,856 7 Patented Apr. 16, 1957 cylinder 19 to the upper end of which is pivotally attached by means of the pins 22 a lifting and positioning bail 21. Fitting slidably within the cylinder 19 is a piston 27 which in turn is attached'to an elongated tubular member 26 which may be referred to as a hollow piston rod or a plunger. An annular seal 28 prevents fluid flow past the piston. The plunger extends out of each end of the cylinder through tight fitting openings provided with packing 29. The lower end of the piston rod or plunger is provided with a nose 31 holding a plug 32 that closes off the lower end of the bore of the plunger. plug is held in place by means of a shear pin 33.

Fixed to the lower exterior of the plunger is an inflatable packer 34 that is held in place at its lower end in an annular groove in the top end of the nose 31 and which is attached at its upper end to a metal sleeve 35 that is slidably positioned on the exterior of the plunger to permit expansion of the packer. Leakage of fluid out of the packer past the sleeve is prevented by the seal 36. Communicating with the interior of the packer is a port 37 in the wall of the tubular member 26. A check valve 38 is provided in the port 37 to maintain fluid pressure in the packer when it has ben inflated.

v A port 40 in the wall of the cylinder at its upper end permits entry of fluid into the cylinder above the piston, while fluid entry into the cylinder below the piston is pr0- vided by a conduit 41. Fluid for raising or lowering the piston can be supplied through high pressure hoses 42 and 43. A third high pressure hose is attached to the upper open end of member 26. This opening can be closed off by a valve 44, which may be a hand valve, as shown, or a check valve. This valve serves as a means of control if the pumps should fail during the killing of the well and also permits the hose 45 to be disconnected after the well has been killed.

The operation of the device can be described with the aid of Figure 2, the dotted outline showing the apparatus as it approaches the vertical position and the solid lines showing the apparatus in the vertical position. The split bracket has been clamped or welded to the casing and the rods 17 have been inserted into the sleeve 16 from one side of the well. The assembled apparatus can be raised to a vertical position by suitable means such as a crane operating from a barge. The crane hook 23 lifts the bail 21 which then moves the assembly toward its vertical position. The entire assembly pivots about the bracket hinge pin as the bail is raised. The stops 24 fastened to the bracket 12 prevent the assembly from going past center once it is in a vertical position.

As the assembly approaches a vertical position fluid pressure may be applied through hose 42 to drive the piston downward and thus extend the plunger toward the open casing. Once the apparatus is in the vertical posi tion full pressure is applied behind the piston and the plunger inserts the packer into the casing. When the piston reaches the end of its down stroke, pressure is ap plied to inflate the packer by pumping fluid through the hose 45 into the tubular piston rod. Once the packer has been fully expanded the well will be shut in. The purpose of the pressure hose 43 and conduit 41 is to provide for upward travel of the piston in case it is necessary to raise the plunger if the plunger has been moved too far downwardly before the apparatus has been placed in a vertical position. No provision is made for deflating the packer, as it is considered that the packer is expendable.

Once the well blowout has been stopped heavy mud can be pumped into the Well by raising the pressure within the tubular member 26 sufiiciently to shear the pin 33. Conveniently the pin can be designed to shear at approximately double the pressul req ired to fully inflate the packer.

The

It is to be understood that this invention is not limited to the specific structures hereinbefore described and that modifications and variations thereof that do not depart from the spirit and scope of the invention will occur to those-skilled in the art. The scope of the invention is defined in the'appended claimsl What is claimed'is:

1. An apparatus for closing off fluid flow from an open eased well which comprises a cylinder, a piston movable within said cylinder, a plunger attached to said piston and extending through one end of said cylinder, supporting means attachable to the well casing and said cylinder and'adapted to support sai'd'cylinder in longitudinal alignment with the-well casing and with the plunger extending toward said casing, an expansible packer mounted to the free end of said plunger, means to apply fluid pressure to said piston and thereby drive said packer into said casing, and means to expand said packer within the casing.

21 An apparatus for closing off fluid flow from an open cased'wellwhiehcomprises an enclosed hollow cylinder attachable to the well casing and adapted to be supportedabove and in longitudinal alignment with said casing, 'a piston movable within said cylinder, a plunger attached to said piston and extending through the lower end' of said cylinder'in a movable fluid-tight relation, an expansible packer mounted on the lower end of said plunger, means to apply fluid pressure to said piston and thereby insert said packer into said casing, and means to expand-said pack-er afterits insertion in the casing.

3. An apparatus for closing off fluid flow from an open cased well having casing extending upward out of the well which comprises a piston an elongated cylinder adapted to receive said piston, supporting means pivotally attached to said casing and to said cylinder and adaptable to support said cylinder above said casing with the longitudinal axis of the cylinder in substantial alignment with the longitudinal axis of the casing, 21 plunger attached to said piston and extending through the lower end of said cylinder in a movable fluid-tight relation, an expansible packer mounted on the lower end of said plunger, means for applying fluid pressure to said piston to insert said packer within said casing, and means to expand said packer following its insertion within said casing.

4. An apparatus for closing ofi fluid flow from an open cased Well having casing extending upward out of said well which comprises a hollow fluid-tight cylinder, supporting meanspivotally attached to said casing and to said cylinder and adapted to support said cylinder above saidcasing with the longitudinal axes oi the cylinder and the casing in substantial alignment, a piston positioned within and movable along the length of said cylinder, a rod attached to said piston and extending out the lower end of said cylinder, said rod being slidably movable relative to said cylinder in a fluid-tight manner, a fluid passageway extending through said piston and the length of said rod, an exp-ansible packer attached to the outer surface of the lower end of said rod, means to apply fluid ressure within said cylinder and abovesaid piston so as to insert said packer into'said casing, means to apply fluid pressure within said passageway to expand said packer, a releasable plug within the lower end of said passageway to prevent fluid flow therethrough until said packer has been expanded.

5. An apparatus as defined in claim 4 in which said plug is releasable in response to a predetermined fluid pressure within said passageway.

6. An apparatus for closing off fluid flow from an open cased well having casing extending upward 'out of the well which comprises a piston, a fluid-tight cylinder adapted to receive said piston, supporting means pivotally attached to said casing and to said cylinder and adaptable to support said cylinder above the casing with the longitudinal axes of the cylinder and the casing in substantial alignment, a piston rod attached to and piercing said piston and extending out of the lower end of said cylinder in a slidable fluid-tight relation therewith, a packer expansible in response to fluid pressure attached to the lower portion of said rod, a fluid passageway within said rod, means to References Cited in the file of this patent UNITED STATES PATENTS 1,664,643 Rasmussen Apr. 3, 1928 1,828,124 Bower Oct. 20, 1931 2,374,765 Mauldin May 1, 1945

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