US3486759A - Sealing of underwater equipment - Google Patents

Description

Dec. 30, 1969 G. E. LEWIS SEALING OF UNDERWATER EQUIPMENT 2 Sheets-Sheet 1 Filed Aug. 25, 1967 I INVENTOR. 050265 E. LEW/5 fi/M #454701 firroe/ves s.

Dec. 30, 1969 I 5. E. LEWIS 3,486,759

SEALING OF UNDERWATER EQUIPMENT Filed Aug. 25, 1967 v 2 Sheets-Sheet 2 I I ra- 4. A

64 17 INVENTOR. fifiaeas LEW/5 Q7702 NEVS.

United States Patent 3,486,759 SEALING OF UNDERWATER EQUIPMENT George E. Lewis, Arcadia, Califi, assignor to Hydril Company, Los Angeles, Calif., a corporation of Ohio Filed Aug. 25, 1967, Ser. No. 663,279 Int. Cl. F16j 15/40, 15/44; B65d 53/00 US. Cl. 277-73 Claims ABSTRACT OF THE DISCLOSURE The disclosure concerns lockable and unlockable apparatus for displacing a sealing annulus into pressure sealing engagement with an underwater cylindrical member such as well casing.

BACKGROUND OF THE INVENTION This invention relates generally to sealing off underwater equipment, as for example cylindrical members. More specifically, the invention concerns apparatus for displacing a sealing annulus into pressure sealing engagement with an underwater cylindrical casing, or the like, and for locking the displaced annulus in engaged position.

In offshore underwater installations, it may become desirable to establish a seal about a tubular member, such as well casing. In addition, maintenance of the established seal may be needed over long periods of time, after which it may be desirable to release the seal. While fluid actuating pressure may be used to displace an actuator, as described in US. Patent 2,609,836, the actuator must be capable of being mechanically held in seal actuated position so that fluid actuating pressure may be released. Also, the actuator must be capable of being released from mechanically held position.

SUMMARY OF THE INVENTION It is a major object of the invention to provide apparatus capable of performing the above-referred to functions in a foolproof, efiicient manner, particularly at underwater locations. The environment of the invention includes a housing having a vertical bore, a packer comprising a massive annulus of resilient material and positioned within the housing with the packer and housing bores in general alignment to receive a tubular member vertically therethrough, and circumferentially spaced metallic inserts carried by and embedded in the packer to move radially with it while the housing retains the inserts against axial dislodgment from the housing; and a fluid pressure responsive actuator subject to bodily advancement vertically in and relative to the housing for applying inwardly directed pressure to the outer peripheral face of the packer thereby to compress and contract the packer radially so as to seal against the received member.

In this environment, the invention is directed to the provision of locking means carried by the housing for controllably blocking retraction of the actuator in a series of positions within the range of actuator vertical advancement, and for unblocking such retraction. Typically the actuator has a series of vertically spaced peripherally exposed shoulders, and the locking means includes a dog movable generally radially to engage and disengage such shoulders in various vertical positions of the actuator. Also, the shoulders typically may extend annularly of the periphery of the actuator, and a series of locking dogs may be spaced circumferentially about the actuator in proximity with it.

In order to secure release of the actuator, the actuator and housing typically may form an auxiliary pressure chamber and the locking means may include a piston surface exposed to pressure in that chamber for urging the 3,486,759 Patented Dec. 30, 1969 locking dog or dogs out of engagement with the actuator peripheral shoulders. In this regard, the locking dogs may be spring-urged radially inwardly for ratchet engagement with the actuator shoulders during upward advancement of the actuator.

These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following detailed description of the drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view, taken in section, to show an application of the invention;

FIG. 2 is an enlarged vertical section illustrating details of one preferred form of the sealing equipment, in open condition;

FIG. 3 is an enlarged fragmentary section showing details of the locking means in engaged condition;

FIG. 4 is a view like FIG. 2, but showing the equipment in closed condition;

FIG. 5 is a view like FIG. 3, but showing the locking means in released condition;

FIG. 6 is a horizontal section taken on line 66 of FIG. 4; and

FIG. 7 is a vertical section taken on line 7-7 of FIG. 4.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 illustrates one possible use for the sealing equipment of the invention generally identified at 10. The cylindrical housing 11 is received downwardly in a recess 12 formed in a base 13, and a suitable seal ring 14 seals off between the housing and base. A tubular member 15, such as oil well casing, is received downwardly through the equipment, and projects downwardly through the base 13 and into a well bore 16. Communication between the bore 16 and the exterior 17 is sealed off by virtue of the seal established between the equipment 10' and the member 15, as will be described.

Extending the description to FIGS. 2 and 3, the housing 11 is annular in shape, and includes an annular shell 17 and integral base 18, an upright inner sleeve 19 bolted at 20 to the base, and an upper cap 21 downwardly reentrant at 22. The shell is externally flanged at 24 for attachment of lifting and lowering tooling. Also, the housing bore is typically defined by the inner bore 25 of the sleeve and by the inner bore 26 of the cap 21.

Positioned coaxially within the housing is a packer 30 comprising a massive annulus 31 of resilient material adapted to receive the tubular member 15 in coaxial vertical relation. As also shown in FIGS. 6 and 7, circumferentially spaced metallic inserts 32 are carried by and embedded in and bonded to the packer to move radially with it (as for example between the positions illustrated in FIGS. 2 and 4), while the housing retains the inserts against axial dislodgement from the housing. Note in this regard, the insert upper and lower plates 35 and 36 integral with and interconnected by the webs 37; the plates 35 slidably engaging the undersurface 38 of the cap 21 along a radial plane, and the plates 36 slidably engaging the upper terminal 39 of the sleeve 19. As the annulus 31 is urged inwardly to FIG. 4 position, in the manner to be described, the resilient material is extruded inwardly at 31a to sealingly and forcibly engage the periphery of the member 15. Such functioning is also described in the Knox Patent 2,609,831 referred to above. In this regard, the inserts 32 retain the resilient material 31 against fluid pressure induced separation from the assembly. Such material may comprise rubber or neoprene of d-urometer hardness of about however, this is by way of example only.

The combination of the invention also includes a fluid pressure responsive actuator subject to bodily advancement vertically in and relative to the housing for applying inwardly directed pressure to the outer peripheral face 42 of the packer, thereby to compress and contract the packer radially so as to seal against member 15 as described. One such actuator is illustrated at 43 in the drawings to comprise a cylindrical section 44 and a downwardly tapered section 45, integrally interconnected at 46. The taper of section 45 is such as slidably to engage the packer face 42, as is clear from FIGS. 2, 3 and 4. Also, the upper portions of sections 44 and 45 fit in upwardly nested relation into the annular recess 47 formed by the housing parts 17 and 21. During such actuator stroking in underwater environment, sea water may flow freely into and out of recess 47 through spaces 48 formed between inwardly tapering upper plates 35 of the inserts, and above the top surface of the packer rubber, as seen in FIG. 7. Likewise, water may flow freely into and out of the cavity 49 formed by section 45 and housing part 19, via spaces 50 formed between inwardly tapering lower plates 36 of the inserts, and below the lower surface of the packer rubber. Water pressure in recess 47 and cavity 49 exerts downward force on the actuator.

The actuator and housing together form a main pressure chamber 53 generally below the actuator for reci-ving gas or liquid under pressure acting to urge the actuator upwardly. Such fluid pressure is communicable to chamber 53 via a pressure source 54, valve 55, flexible line 56, fitting 57 and standpipe 58. The latter extends vertically to terminate near the top of chamber 53 in order that suflicient liquid will remain in the chamber 53 to cushion downward retraction of the actuator as liquid is displaced to flow out the standpipe. When valve 55 is turned to release the pressure in chamber 53, the actuator descends to FIG. 2 position, and fluid leaves the chamber 53 to flow via line 56 to the valve exit path indicated at 59.

The actuator carries annular bearing surfaces 60, 61 and 62 slidably engaging the inner walls of housing parts 19 and -17, as shown. Seals 63, 64 and 65 at the respective bearing surfaces seal off between the actuator and housing, whereby not only is chamber 53 sealed, but an auxiliary pressure chamber 66 is also sealed oil. The latter chamber is formed between the actuator section 44 and housing member 17, to extend between seals 64 and 65, and pressure is typically delivered to that chamber from a source 68 via valve 69, line 70 and fitting 71. Such pressure in chamber 66 serves the actuator releasing purpose, as will be described.

The combination of the invention also includes locking means carried by the housing for controllably blocking downward retraction of the actuator in a series of positions within the range of actuator vertical advancement, and for unblocking such retraction. In the illustrated example, the locking means includes a series of locking dogs 75 spaced circumferentially about the actuator in proximity with it. Each dog is movable generally radially to engage and disengage shoulders 76 on the actuator in various vertical positions of the latter. Step shoulders 76 extend annularly at the periphery of the actuator, and are vertically spaced to project outwardly away from the axis 77 of the actuator. Similarly, step shoulders 78 are carried on the dogs 75, to extend beneath shoulders 76 for supporting the actuator against downward retraction. The shoulders 76 and 78 are formed on ratchet teeth cam angled at 79 and 80 to allow upward displacement of the actuator relative to dogs 75; however, yieldable means such as springs 81 urge the dogs inwardly toward supporting engagement with shoulders 76, whereby the actuator will not be released in the absence of release or disengagement of the dogs from shoulders 76. Each compression spring '81 is confined within a cylinder 83 and between a 'Wall 84 and a plunger flange 85. The latter is attached via a rod 86:: With the dog 75 59 that spring 4 force urges the dog inwardly. Cylinder 83 is bolted at 85a to the wall 17.

The locking means also includes piston surfaces exposed to pressure in the auxiliary chamber 66 for urging the locking dogs simultaneously out of supporting engagement with the actuator shoulders 76, so that the actuator may be released for down-ward travel. In the illustrated example, the piston surfaces are formed at 85b on the plunger flange 85, directly exposed to the interior of chamber '66. Sufficient fluid pressure introduced into the latter urges the dogs outwardly against resistance imposed by springs 81, and until the rear faces 86 of the dogs seat at the interior surfaces 87 of the recesses 88 in which the dogs are received and guided.

As is clear from the foregoing, the actuator 43 is automatically locked in each of a series of vertical positions as it rises, so as to block it against downward release whereby the packer may be locked in each of a series of inward displaced positions of contraction, as may accommodate sealing with different sized members 15. This of course assumes absence of suflicient fluid pressure in chamber 66 as would retract the latch dogs. When release of the packer is desired, fluid pressure in chamber 66 is increased to retract the dogs, and fluid pressure in chamber 53 is decreased, to allow the actuator to descend, water pressure in chamber 47 and cavity 49 aiding such downward retraction of the actuator.

I claim: 1. In combination with a housing having a vertical bore therethrough, a packer comprising a massive annulus of resilient material and positioned within the housing with the packer and housing bores in general alignment to receive a tubular member vertically therethrough, and circumferentially spaced metallic inserts carried by and embedded in the packer to move radially therewith while the housing retains the inserts against axial dislodgment from the housing, the improvement comprising, a fluid pressure responsive actuator subject to bodily advancement vertically in and relative to the housing for applying inwardly directed pressure to the outer peripheral face of the packer thereby to compress and contract the packer radially so as to seal against said member, said actuator and the housing forming a main fluid pressure receiving chamber,

and locking means carried by the housing for controllably blocking retraction of said actuator in a series of positions within the range of actuator vertical advancement, and for unblocking said retraction,

said actuator and housing forming an annular auxiliary chamber to receive fluid pressure acting on said locking means to elfect displacement thereof for unblocking said actuator retraction, and structure sealing oif between the actuator and housing at spaced locations to block escape of fluid pressure from said auxiliary chamber.

2. The combination of claim 1 wherein said actuator has a series of vertically spaced peripherally exposed shoulders, and said locking means includes a locking dog movable generally radially to engage and disengage said shoulders in various vertical positions of the actuator.

3. The combination of claim 2 in which said shoulders extend generally annularly at the periphery of the actuator, and said locking means includes a series of said locking dogs spaced circumferentially about said actuator in proximity therewith.

4. In combination with a housing having a vertical bore therethrough, a packer comprising a massive annulus of resilient material and positioned within the housing with the packer and housing bores in general alignment to receive a tubular member vertically therethrough, and circumferentially spaced metallic inserts carried by and embedded in the packer to move radially therewith while the housing retains the inserts against axial dislodgment from the housing, the improvement comprising,

a fluid pressure responsive actuator subject to bodily advancement vertically in and relative to the housing for applying inwardly directed pressure to the outer peripheral face of the packer thereby to compress and contract the packer radially so as to seal against said member, said actuator and the housing forming a main fluid pressure receiving chamber,

and locking means carried by the housing for controllably blocking retraction of said actuator in a series of positions within the range of actuator vertical advancement, and for unblocking said retraction,

said actuator having a series of vertically spaced peripherally exposed shoulders, and said locking means including a locking dog movable generally radially to engage and disengage said shoulders in various vertical positions of the actuator,

the actuator and housing forming an auxiliary pressure chamber, and said locking means including a piston surface exposed to pressure in said chamber for urging the locking dog out of engagement with said shoulders.

5. The combination of claim 4 including yieldable means for urging said locking means radially inwardly for engaging said shoulders.

6. The combination of claim 3 in which said locking dogs are located radially outwardly of said packer in all positions of the actuator.

7. In combination with a housing having a vertical bore therethrough, a packer comprising a massive annulus of resilient material and positioned within the housing with the packer and housing bores in general alignment to receive a tubular member vertically therethrough, and circumferentially spaced metallic inserts carried by and embedded in the packer to move radially therewith while the housing retains the inserts against axial dislodgment from the housing, the improvement comprising,

a fluid pressure responsive actuator subject to bodily advancement vertically in and relative to the housing and applying inwardly directed pressure to the outer peripheral face of the packer thereby to compress and contract the packer radially so as to seal against said member, said actuator and the housing forming a main fluid pressure receiving chamber,

and locking means carried by the housing for controllably blocking retraction of said actuator in a series of positions within the range of actuator vertical advancement, and for unblocking said retraction,

said actuator having a series of vertically spaced peripherally exposed shoulders, and said locking means including a locking dog movable generally radially to engage and disengage said shoulders in various vertical positions of the actuator, said shoulders extending generally annularly at the periphery of the actuator, and said locking means including a series of said locking dogs spaced circumferentially about said actuator in proximity therewith,

said housing having radially spaced inner and outer tubular wall sections between which the actuator is received, the actuator and said outer wall having sealing interengagement at vertically spaced locations straddling said locking dogs, the actuator and said inner wall having sealing interengagement below said packer.

8. The combination of claim 4 in which the actuator and housing form a main pressure chamber generally below the actuator for receiving fluid pressure acting to urge the actuator bodily upwardly in the housing.

9. The combination of claim 7 including a stand-pipe in said main fluid pressure receiving chamber below the actuator to deliver fluid pressure into the upper interior of said chamber.

10. The combination of claim 4 including means to selectively deliver fluid pressure to said main and auxiliary pressure chambers.

References Cited UNITED STATES PATENTS 1,811,013 6/1931 Humason 277114 2,904,357 9/1959 Knox 27773 X 3,182,566 5/1965 Berg et al. 92-24 3,222,075 12/ 1965 Haeber 277-9 SAMUEL ROTHBERG, Primary Examiner US. Cl. X.R.

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