US3740017A

US3740017A - Clamping device for closing an uncontrollably flowing submerged well

Info

Publication number: US3740017A
Application number: US00102688A
Authority: US
Inventors: I Pogonowski
Original assignee: Texaco Inc
Current assignee: Texaco Inc
Priority date: 1970-12-30
Filing date: 1970-12-30
Publication date: 1973-06-19
Anticipated expiration: 1990-06-19

Abstract

The invention relates to an apparatus which embodies a clamping device that is submergible, and remotely operable to close an offshore well casing and flow line. The apparatus includes a clamping head formed with spaced apart arms which define an opening for engaging the well casing. A displaceable truss is carried on one arm and engageable with the other whereby to fasten said clamping device to the casing prior to actuation of a hydraulic ram which deforms the casing and flow line to minimize or preclude fluid flow therethrough.

Description

United States Patent Pogonowski [76] Inventor: Ivo C. Pogonowski, c/o Texaco 1nc.,

P.(). Box 425, Bellaire, Tex. 77401 [22] Filed: Dec. 30, 1970 [21] Appl. No.: 102,688

[52] 11.8. CI. 251/5, 166/5 [51] Int. Cl. F161 55/14 [58] Field of Search 166/5, 55, 55.1,

[56] References Cited UNITED STATES PATENTS 2,599,958 6/1952 Wallis 251/5 2,680,000 6/1954 Pulver 251/8 3,099,316 7/1963 Johnson 166/.6 1,949,672 3/1934 Barrier 166/55 3,215,202 11/1965 Pollard et a] 61/69 R June 19, 1973 FOREIGN PATENTS OR APPLICATIONS 257,902 9/1927 Great Britain 251]] Primary ExaminerJoseph H. McGlynn Assistant Examiner-Lawrence J. Staab Attorney-Thomas H. Whaley and Carl G. Rics [57] ABSTRACT The invention relates to an apparatus which embodies a clamping device that is submergible, and remotely operable to close an offshore well casing and flow line. The apparatus includes a clamping head formed with spaced apart arms which define an opening for engaging the well casing. A displaceable truss is carried on one arm and engageable with the other whereby to fasten said clamping device to the casing prior to actuation of a hydraulic ram which deforms the casing and flow line to minimize or preclude fluid flow there through.

7 Claims, 6 Drawing Figures PAIENIED 3. 740.01 7

sum 1 or 2 Pummm x m smaorz z 2 4 7 4 I 2 G H w A. 3 2 B F u NHL 2 v HT a a 6 T FIG. 6

CLAMPING DEVICE FOR CLOSING AN UNCONTROLLABLY FLOWING SUBMERGED WELL BACKGROUND OF THE INVENTION Increasing sources of crude oil and natural gas are being found at offshore installations. Wells driven into the floor of such an offshore location normally embody a relatively large casing usually 30 to 48 inches in diameter, which forms an upstanding outer shell. The conductor for crude oil or gas comprises a smaller flow line from about 6 to 10 inches in diameter, which line is psitioned within the casing and extends downwardly to a pressurized source of crude oil.

Under normal conditions, upon completion of such a submerged offshore well, the fluid carrying flow line or riser is provided with the normal Christmas tree arrangement to permit control of the fluids drawn from a pressurized subterranean reservoir.

The Christmas tree or valve arrangement connected to the flow line, is such as to regulate the flow rate of fluids passing from the reservoir, and can be remotely or manually actuated. Where however, unusual circumstances arise such that the well pressure exceeds a controllable level, the fluid, both liquid and gas, will rush uncontrollably from the reservoir.

This uncontrolled escape constitutes not only an economic loss, but carries more pertinent stigma of being a mass pollutant of both the surrounding water and atmosphere. Further, ejection of raw well gases into the atmosphere fosters a firehazard that has often resulted in both material damage and loss of life when such a well erupts and the gases become ignited.

There presently exist a number of means whereby to stem this uncontrolled fluid flow from a subterranean well. Preferably, the wellis capped or plugged in such manner as to either cut off the escaping fluids or permit the latter to be controllably regulated. The apparent danger in such an operation is however, inability to bring personnel such as divers or submarine equipment to the vicinity of the well head whereby to work on the latter.

Toward overcoming a situation as stated above, where a well is uncontrollably emitting large quantities of petroleum fluids, the present apparatus permits the submerged well to be closed to choke off the flow by a remote operation which is effectual and which minimizes the danger to personnel in the vicinity. The well choking device embodies a controllably submerged clamping head which is actuated from the waters surface, and which is lowered in the vicinity of the well head. The apparatus includes a body or carriage having at least two outwardly extending arms which define a slip therebetween for slidably engaging a well head casing. With a well casing flow line positioned between the arms, a supporting truss member is urged into place to confine the casing within the clamping device while simultaneously positioning said members. Thereafter, a remotely actuated clamping head applies external pressure to the casing and the internal flow line, whereby to crush both said members and stem the uncontrolled fluid flow.

DESCRIPTION OF THE DRAWINGS In the drawings, FIG. 1 illustrates a vertical elevation of a subterranean well head which terminates at a surface platform,

with the present clamping device positioned adjacent thereto.

FIG. 2 is a cross-sectional view taken along line 2-2 in FIG. 1 with the clamping device in place.

FIG. 3 is similar to FIG. 2, showing the position of the well casing subsequent to being crushed.

FIG. 4 is an enlarged scgmentary view of the clamping device shown in FIGS. 2 and 3.

FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. 4.

FIG. 6 is an end view taken along line 66 in FIG. 4 with the truss in an open position.

Referring to FIG. 1, the submerged type offshore well is shown generally as consisting of a casing 10 which normally comprises a steel tubular member 30 to 48 inches in diameter. The casing extends from a position near the waters surface to a buried point in the substratum depending upon the consistency and composition of the latter. The casing is fastened in place by cementing or other suitable means as to be rigidly held in its imbedded position. Casing l0 surrounds a centrally positioned flow line 11 which extends downwardly past the lower end of the casing and terminates in a reservoir of oil and/or gas at a desired] depth. Flow line 11 normally comprises connected lengths of drill pipe varying from 6 to 10 inches in diameter, which pipe lengths are threadably connected to form a continuous flow path.

Flow line 1 1 is connected at its upper end to a Christmas tree arrangement 12 presently illustrated by a plurality of valves extending from and communicated with the flow line upper end, to control the flow of liquid and gases passing upwardly from the reservoir. From the Christmas tree, raw fluids are either separated or passed directly by pipeline to a storage facility.

It is appreciated that the present arrangement of casing 10 and flow line 11, together with the above surface Christmas tree, is illustrative of the number of variations that could be applied to an offshore well. For example, in many instances the entire unit including flow line and Christmas tree are submerged and remain at the floor of the body of water whereby to minimize the possibility of said equipment constituting a navigational hazard. In such an instance, the well head is remotely operated to control fluid flow by use of any of several .systems. The latter includes pneumatic or electrical systems which connect to actuators for the various valves. Further such submerged well heads are communicated with a storage area of the produced fluids by underwater flow lines which extend from the well head to a suitable gathering point either onshore, or at other submerged areas.

Referring again to FIG. I, the instant clamping device 13 is illustrated in a partially submerged condition whereby to engage and be positioned about casing 10 at a point between the waters surface and the ocean floor. The clamping device includes a clamping body 14, having at least two parallel positioned

arms

16 and 17 extending therefrom and spaced apart to define a slip area therebetween. Referring to FIG. 2, the respective arms form ajuncture at one end with body 14, and at the other end support a cross truss 18 which extends between the ends of the respective arms.

In the open position, as shown in FIG. 6, the clamping device is manipulated from the waters surface to register well casing 10 between the

respective arms

16 and 17. Cross truss 18 is thereafter in an upstanding position and subsequently actuated downwardly to engage arm 16 and form a closure about the casing 10.

The entire unit is positioned at a desired water level by any of several means which include either a fixed floating guide member 19, or a controllably buoyant arrangement. In the latter instance the entire clamping device will be submerged beneath the waters surface and thereafter manipulated to engage casing 10. In the instance shown, clamping apparatus 13 is manipulated into place by means of the float apparatus 19 which is connected by cables 20 to a pair of powered surface vessels.

It is understood that toward positioning clamping device 13, the remote operation thereof can be facilitated by use of underwater systems such as cameras and/or closed TV circuits, together with other guiding means which would function regardless of the turbulence and condition of the water in the vicinity of the uncontrollable well.

In the embodiment shown, clamping body 14 comprises in essence an elongated bifurcated member. The body forms a juncture with

spacedapart arms

16 and 17 which extend from the body normally in a horizontal plane. The arms are fastened to body 14 by welding, or otherwise being firmly connected thereto to give the unit sufficient strength to withstand the subsequent tensional stresses applied thereto.

Each arm as shown in FIGS. 4 and 5, comprises an elongated member which can be of solid construction, or of circular cross-section with a sufficiently thick wall to provide the necessary tensional strength. Said

arms

16 and 17 can of course assume any desired crosssectional configuration which would provide the necessary rigidity to facilitate the apparatus clamping function.

The remote end of each arm such as 16, is provided with an end cap 22 firmly depending therefrom, which includes an annular shoulder 23. The latter extends outwardly from the arm surface to receive a corresponding shoulder of the cross truss member 18.

Cross truss member 18 includes a composite, beamlike element 24 having a terminal connector at each opposed end. Terminal connector 26 includes a hub having a central opening 27 extending therethrough to slidably register on sleeve bearing 28 carried on arm 17. The hub includes an outer shoulder which slidably engages the corresponding shoulder of the arm end cap.

Cross truss 18 other end comprises a latching arrangement including a rigid upper jaw 29 which depends outwardly from the cross truss end, and a movable lowerjaw 31 which cooperates with said upper jaw 29 at ajoint formed by a hinge pin 32. As shown in FIG. 6, when in the open position, lower jaw 31 is displaced from the upper jaw 29 by actuation of hydraulic cylinder 33 connected to said lower jaw at a pivotal connection 34. When cross truss 18 is in the engaged position on the arm 16, and lower jaw 31 is actuated to its closed position, a locking pin 36 is urged through the aligned jaw openings within the respective jaw halves by a locking pin actuating mechanism 37 carried on arm 16.

Cross truss member 18 as previously noted, engages the outer wall of casing whereby to crush the latter. Said truss 18 can therefore be provided with an anvillike, hardened metal seat 38 extending outwardly therefrom to provide a desired configuration of crushwhich depends horizontally therefrom in a direction substantially parallel with the two

arms

16 and 17. Said hydraulic cylinder in the usual manner, includes a piston 41 which is reciprocally removable through the cylinder. The piston 41 outer end carries a clamping head 42. The function of said clamping head 42 is to engage the outer surface of casing 10 or flow line 11 and to position the same during the crushing operation. Thus, as hydraulic cylinder 39 is remotely actuated to urge piston 41 therefrom, clamping head 42 will engage one side of well casing 10 diametrally opposite to anvil 38, thereby applying a radial crushing force to the casing 10 opposite side.

The clamping device is adapted for operation at various water depths or adjacent the ocean floor, by means of a flotation apparatus. Since the area about an uncontrollably flowing well may not be readily approachable either due to the condition of the water or to fire, the device is remotely actuated to bring it into proper position for engaging casing 10. Thus, and as shown in FIG. 1, float mechanism 19 includes spaced apart flotation tanks which are spaced upwardly from body 14 and

arms

16 and 17, by

support members

43 and 44. The latter are preferably adjustable either through the use of telescoping members, or flexible cables whereby to permit lowering of the clamping head to a desired operating depth. I

Operationally, clamping device 13 is normally floated as shown in FIG. 1, with the clamping head submerged a desired depth beneath the waters surface, and supported by flotation gear 19. The entire unit can be propelled by an underwater source and guided by divers or the like, however for the present description it is manipulated into place by cables such as 20, attached at appropriate places to each of the floats. The latter are then towed by boats disposed to opposite sides of the well casing 10, whereby

arms

16 and 17 straddle the casing.

The clamping device 13 is propelled toward casing 10 with the cross truss 18 in the displaced or open position as shown in FIG. 6, to permit the

respective arms

16 and 17 to register about the casing. Thereafter, when the casing abuts clamping head 42, the cross truss 18 control cylinder 44 is actuated to bring said cross truss into engagement with the arms 16. Underjaw 31 is then closed to engage upper jaw 29, and locking pin 36 is urged into place whereby the two

arms

16 and 17 and the truss 18 form a rigid unit. Actuation of the hydraulic cylinder 39 urges head 42 against the casing 10 which is deformed inwardly. The inward deformation is continued until the centrally positioned flow line 11 is likewise crushed to discontinue further fluid flow through the flow line 11.

With the fluid flow in the flow line 11 now substantially or completely discontinued, the line can be provided with a more permanent plug such as by cementing or through the usual methods for closing a well. The clamping mechanism can now be removed by returning cross truss 18 to its original upright position, and withdrawing the clamping device 13 from the casing 10 such that the said device can be floated clear of the well area.

Other modifications and variations of the invention, as hereinafter set forth, may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

I claim:

1. Apparatus for closing an uncontrollably producing submerged well at the floor ofa body of water, said well having a fluid flow line communicated with an underground pressurized source of fluid, and an upstanding casing surrounding said flow line for a portion of the latter between the waters surface and said floor, which apparatus includes;

a clamping body,

a pair of arms extending from said body defining a slip therebetween,

a truss pivotally connected to one of said arms, and being rotatably movable about the longitudinal axis of said one arm to engage the other of said arms,

latching means carried on one end of said truss for engaging and removably fastening to said other arm,

said latching means being movable relative to said truss between a first position permitting said truss to be rotated away from said other arm and a second position locking said truss on said other arm,

a clamping head depending from said body, being actuable in a direction toward said truss whereby to engage said casing and flow line therebetween, and to deform said respective casing and flow line to substantially close the flow line to fluid passing therethrough.

2. Apparatus as defined in Claim 1, including; remotely actuated means connected to said one end of said truss, and being actuable to rotatably actuate said truss, whereby to be displaced about said one arm and to engage the truss latching means with the other of said arms.

3. Apparatus as defined in claim 1 including; float means connected to said body for regulating the sub merged depth of said body in said water.

4. Apparatus as defined in claim 3 wherein said float means includes; a plurality of controllably buoyant floats being spaced apart to define an opening therebe tween, whereby to be spaced adjacent to said flow line when said pair of arms are spaced about said flow line.

5. In an apparatus as defined in claim 3, including ca bles attached to said respective float means to be disposable about said submerged well, whereby to draw the clamping body into contact with the well.

6. ln apparatus as defined in claim 2, wherein said means for actuating said arm for adjusting the position of said truss includes, a fluid powered cylinder connected to said truss and to said body respectively,

7. In an apparatus as defined in claim 2, wherein, said latch means includes a pair of cooperating jaws pivotally connected to be actuated between open and closed positions, whereby to engage said other arm.

Claims

1. Apparatus for closing an uncontrollably producing submerged well at the floor of a body of water, said well having a fluid flow line communicated with an underground pressurized source of fluid, and an upstanding casing surrounding said flow line for a portion of the latter between the water''s surface and said floor, which apparatus includes; a clamping body, a pair of arms extending from said body defining a slip therebetween, a truss pivotally connected to one of said arms, and being rotatably movable about the longitudinal axis of said one arm to engage the other of said arms, latching means carried on one end of said truss for engaging and removably fastening to said other arm, said latching means being movable relative to said truss between a first position permitting said truss to be rotated away from said other arm and a second position locking said truss on said other arm, a clamping head depending from said body, being actuable in a direction toward said truss whereby to engage said casing and flow line therebetween, and to deform said respective casing and flow line to substantially close the flow line to fluid passing therethrough.

3. Apparatus as defined in claim 1 including; float means connected to said body for regulating the submerged depth of said body in said water.

4. Apparatus as defined in claim 3 wherein said float means includes; a plurality of controllably buoyant floats being spaced apart to define an opening therebetween, whereby to be spaced adjacent to said flow line when said pair of arms are spaced about said flow line.

5. In an apparatus as defined in claim 3, including cables attached to said respective float means to be disposable about said submerged well, whereby to draw the clamping body into contact with the well.

6. In apparatus as defined in claim 2, wherein said means for actuating said arm for adjusting the position of said truss includes, a fluid powered cylinder connected to said truss and to said body respectively.