US3868826A

US3868826A - Clustered and protected pressure lines for setting sleeve packers

Info

Publication number: US3868826A
Application number: US459586A
Authority: US
Inventors: Don B Landers
Original assignee: Oil States Rubber Co
Current assignee: Oil States Industries Inc
Priority date: 1974-04-10
Filing date: 1974-04-10
Publication date: 1975-03-04
Anticipated expiration: 1992-03-04
Also published as: JPS50138601A; GB1460131A; DE2512865A1; FR2267420A1; FR2267420B3

Abstract

An off-shore deep water marine platform including on each platform leg one or more piling sleeves each intended to receive a piling driven through the sleeves into the bottom of the sea and the sleeves subsequently being secured to the driven piling by cement pumped into the annulus between each piling and its sleeve while the annulus is sealed by inflatable packer means, the improvement comprising improved packer inflating means including flexible lines extending to each packer from a protective access manifold on the platform deck, and these lines being clustered together and run down to the packers through rigid protective pipe including main protector pipes coupled to the manifolds and containing one or more flexible lines and extending down to branch protector pipes extending out from main protector pipes to particular packer locations and containing only the flexible line going to one such packer, and the protector pipes themselves being mounted so as to be protected by the marine platform structure.

Description

Unite States Patent Landers [4 Mar, 4, 1975 [75] Inventor:

[73] Assignee: Oil States Rubber Company,

Arlington, Tex.

22 Filed: Apr. 10,1974

21 Appl. No.: 459,586

Don B. Landers, Arlington, Tex.

[52] 11.8. C1 61/465, 138/110. 166/179, 251/1, 277/128 [51] int. Cl E02d 5/14, Fl6j 15/02 [58] Field of Search 61/465,461, 63, 82; 251/1. 5; 166/179, 186; 138/1 11). 111. 112, 113, 114; 277/128 [561 References Cited UNITED STATES PATENTS 3.468.132 9/1969 Harris 61/63 3,533,241 10/1970 Bowerman et a1 61/465 3702537 11/1972 Landers (ml/46.5

Primary Emmincr-Jacob Shapiro Attorney, Agent, or FirmDowell & Dowell marine platform structure.

[5 7] ABSTRACT An off-shore deep water marine platform including on each platform leg one or more piling sleeves each intended to receive a piling driven through the sleeves into the bottom of the sea and the sleeves subsequently being secured to the driven piling by cement pumped into the annulus between each piling and its sleeve while the annulus is sealed by inflatable packer means, the improvement comprising improved packer inflating means including flexible lines extending to each packer from a protective access manifold on the platform deck, and these lines being clustered together and run down to the packers through rigid protective pipe including main protector pipes coupled to the manifolds and containing one or more flexible lines and extending down to branch protector pipes extending out from main protector pipes to particular packer locations and containing only the flexible line going to one such packer, and the protector pipes themselves being mounted so as to be protected by the 6 Claims, 12 Drawing Figures PATENTED 4|975 sum 2 M3 CLUSTERED AND PROTECTED PRESSURE LINES FOR SETTING SLEEVE PACKERS FIELD OF INVENTION This invention relates to off-shore marine platforms whose supporting legs include tubular piling sleeves with pilings driven therethrough into the bottom of the sea and further include inflatable packers in the sleeves for sealing the annulus between the sleeve and its piling, and more particularly, the invention relates to improvements in pressure line means for setting the individual packers by pressure from a source located above in the vicinity of the deck of the platform.

BACKGROUND AND PRIOR ART It has long been the practice to fabricate a platform structure on land, seal its hollow leg and brace members, and tow it to the site where it is to be installed using the sealed legs as flotation pontoons, thereafter flooding the legs at controlled rates to erect the platform structure at the desired site, for instance, as shown in US. Pat. Nos. 3,145,539 to Estes et al., 3,209,544 to Bormann, 3,486,343 to Gibson et al., and 3,597,930 to Rochelle et al. There are a number of different ways of securing such structures to the bottom of the sea, but the present disclosure is especially concerned with the approach which uses piling driven into the bottom through piling guide sleeves, for instance, as shown in Bormann, US. Pat. No. 3,209,544 where the piling is subsequently made unitary with the sleeve through which it passes by filling the annulus between the piling and the sleeve with cement. The assignee of the present invention is also the owner of US. Pat. No. 3,468,132 to Harris, and US. Pat. No. 3,533,241 to Bowerman et al which teach improved inflatable packer means for sealing such an annulus after the piling is driven in place and prior to filling the annulus with concrete and also teach rupturable diaphragm seals for sealing the ends of the guide sleeves to exclude foreign matter prior to driving of the piling.

The present invention relates to improvements in structures of the general types set forth in the above prior art patents. In the past it has been the practice to run individual inflating lines from the platform deck down to each individual packer, usually along the outside of the leg. Typical platform legs support one or possibly 4, 6, or even more piling guide sleeves, and in cases where one uses two packers per piling at the extreme open ends of each piling sleeve, each leg might have a large number of inflating lines running unprotected down its surface. These inflating lines could be tolerated on a shallow-water platform since they are easily reached for repair in the event of damage, but present platforms are being installed in water as deep as 500 feet in the North Sea or 750 feet off the California Coast where these lines must not be exposed to damage which might cause packer failure, difficult or impossible to repair.

The present teaching employs flexible inflating pressure lines, either singly or clustered together, and protected by rigid protector pipe which economically houses one or a number of clustered flexible lines over the major lengths thereof between the platform deck and the packer levels and protects those lines against damage while the main protector pipes themselves are either located outside of the platform legs or else further protected by being located inside the platform legs. v

- It is the principal object of this invention to provide virtually failure-free inflation lines going to the packers in the platform-leg piling sleeves taking into account the peculiar nature of the problems encountered in pressurizing platform sleeve packers. In the past, rigid metal pipes have been used by themselves to inflate packers and while, because of their strength, they resist crushing damage quite well, their very rigidity prevents them from resisting cracking due to vibration, flexing or expansion and retraction of the platform legs. Moreover, it is expensive to run a dozen or so pipes down a platform leg, where each pipe must be entirely separate since it must control the setting of only one packer. On the other hand, flexible lines such as fabric reinforced lines or even copper tubing have been used to achieve the advantage of their shock and flexure capabilities, but these lines are fragile and easily cut or crushed, and

they have a tendency to twist and lash about when they are pressurized to the very high pressures required to set a packer in deep water.

It is the object of this invention to provide a pressure line system achieving the advantages of both rigid and flexible lines while at the Sametime reducing costs by clustering the main lengths of the flexible lines so that they can be housed in a lesser number of protector pipes. A single 4 or 6 inch main protector pipe running down a platform leg can house 12 or so individual flexible lines from a point above the level of the sea down to branching exit points several hundred feet beneath the surface level, where the individual lines begin fanning out to the packers which they control. From these exit points to the packers, the flexible lines are housed within smaller branch protector pipes of, for instance, one inch diameter which are large enough to pass the one-quarter inch standard pipe thread couplings of the flexible lines. Elbows and junctions of the main and branch protector pipes are designed to avoid sharp turns so that after the protector pipes have been welded to the platform leg structures the flexible lines can easily be drawn through the pipe from the vicinity of each packer up the leg to the platform deck using pullin.g" lines prethreaded through the pipe. The protector pipes are welded to the platform structure on shore during fabrication thereof. This use of rigid piping is economical since the purpose of the pipe is to protect the flexible lines and therefore the protector pipes need not necessarily be fluid-tight. Moreover, only a few of them need be used since many flexible lines are clustered inside of them.

The use of flexible lines protected inside of rigid pipe not only protects the lines while the platform is being fabricated, and while being towed to the site and while being erected thereat, but this combination of lines and pipe is important after the platform is erected and while the pilings are being driven and "the packers set. The pile driving subjects the packers and their inflation lines to tremendous shock and vibration and it is not until after such shock that the inflation lines are used to set the packers. This fact emphasizes the importance of supporting and protecting the flexible lines since they are not used until after they have been subjected to maximum punishment. Failure of a line means failure of its packer during the cementing process. In the drilling platform being built for the North Sea and embodying the present invention the flexible lines, once installed in their protector pipe, are pre-tested for any leakage.

Other objects and advantages of the invention will become apparent during the following discussion of the drawings, wherein:

THE DRAWINGS FIG. 1 is an elevation view of a drilling platform structure showing the locations of protector pipes extending from the platform deck to packers within variously located piling guide sleeves;

FIG. 2 is a partial plan view of the drilling platform;

FIG. 3 is a cross-sectional view taken along line 33 in FIG. 1;

FIG. 4 is a cross-sectional view taken along line 4-4 in FIG. 1',

FIG. 5 is a cross-sectional view of an inflating-line manifold taken along line 5-5 in FIG. 1;

FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. 1;

FIG. 7 is a cross-sectional view taken along line 77 in FIG. 1;

FIG. 8 is a cross-sectional view of a main protector pile illustrating a typical preferred way of passing the pipe through the wall of a platform leg in installations where the inflation line or lines are routed inside the main legs;

FIG. 9 is a cross-sectional view showing the lower end of a typical main protector pipe having four branch protector pipes fanning out from it;

FIG. 10 is a cross-sectional view similar to FIG. 4, but enlarged and showing one possible configuration of branch protector pipes;

FIG. 11 is an enlarged cross-sectional view of the lower end of a piling sleeve with a packer and diaphragm in place, the view being taken along line l1-l1 of FIG. 10; and

FIG. 12 is a view similar to FIG. 10, but showing a somewhat modified placement of the branch protector pipes.

Referring now to FIGS. 1 and 2, these figures show a platform structure having a number of downwardly extending legs supporting a deck 10 in the vicinity of the top of the platform structure. As viewed in FIG. 1, it will be noted that to the left of the figure there is a large diameter leg 12 which extends from the bottom ofthe platform nearly to the top thereof, and just below the water line the diameter decreases at a conical portion 14 to a smaller leg diameter 16 which extends up to the deck 10. To the right of FIG. 1 there is a smaller diameter leg 18 which extends from the platform 10 to the bottom of the structure and in the center of FIG. 1 there is a smaller diameter leg 20 which extends from the bottom of the platform up only through about the first several frames which serve to brace the structure, and are generally referred to by the reference character 22. It will be noted that these same parts appear in FIG. 2 which is a plan view looking down upon the platform, but shows only the near end of the platform, since the legs merely repeat at other locations which are not shown because they add no further details. It is to be understood that the platform structure illustrated in FIGS. 1 and 2 is merely illustrative of a large number of different platforms supported on one or more legs. The large diameter legs such as the leg 12 appear all on the left side of the platform as shown in FIGS. 1 and 2, and this larger leg diameter is leg diameter is provided so that it can be sealed at both ends and serve as one of several pontoons on which the rig can be floated to the desired location.

FIG. 3 shows a preferred embodiment in which the larger diameter legs 12 comprise double-wall structures having an inner wall 11 which can be seen not only in FIG. 3, but also in FIGS. 4, 10, and 12. In the vicinity of the lower end of each of the platform legs there are one or more piling guide sleeves, the sleeves being clustered where there are a number of these grouped as in FIGS. 1 and 2 and labelled 24, 25, 26, 27, 28 and 29, the

sleeves

24 and 25 also being visible in FIGS. 10 and 12. FIG. 11 also shows a detailed view of the bottom end of the sleeve 25 and illustrates the seal structures appearing therein. For the sake of clarity, a piling such as extends through a piling sleeve 25 is illustrated only in FIGS. 1 and 11, and bears the references numeral 30. The piling sleeves 24 through 29 inclusive are respectively supported on the platform legs at which they are shown, FIGS. 10 and 12 illustrating brackets generally referred to by the reference numeral 32, which brackets are welded on the leg 12 and are also welded to the sleeve members 24 through 29, respectively to support them parallel to the platform leg, although slightly offset therefrom. In the present illustrative embodiment, each platform leg has four such piling sleeves attached to it, but this is an arbitrary selection,

and platform legs frequently have other numbers of sleeves attached to them, generally from two to eight such sleeves per leg. Each sleeve is provided with a conical flared upper end such as the upper end 31 shown in FIG. 1 for the purpose of facilitating insertion of the piling after the platform has been erected.

The present disclosure is concerned with the installation of packers either at the bottom of the piling sleeves, or else both at the top and the bottom of each piling sleeve. FIG. 11 shows a typical illustration including a packer 34 mounted within the leg 25 and supported at its upper and lower ends in

rings

36 and 37, the packer having an inflation spud 38 extending through the wall of the sleeve 25 and having a length of pipe ending at its upper end in a quarter inch fitting 39 which is supported in a block 40 to receive a flexible line coupling in a manner about to be described. This piling sleeve structure as shown herein for illustrative purposes also includes a rupturable diaphragm 42 closing it lower end in a manner well known in the prior art and positioned such that the piling 30 when driven downwardly will pass through the diaphragm into the earth beneath the bottom of the sea, the diaphragm 42 preventing the rise of detritis into the piling guide 25 while the platform is being erected in place and before the pile is driven.

The inventive concept concerns the manner in which fluid pressure such as air is applied to each of the packers 34 from a pressure source such as a cylinder or a pump P located at the top of the platform, and in the present illustration shown as being mounted on the deck 10 with a pressure hose I-I extending from the source as shown in FIG. 2. Mounted in the vicinity of the deck near the sleeve is a series of manifold outlets each one of which contains a number of pressure fittings to which the hose H can be selectively applied in order to inflate the packer unit 34 which is connected to that particular pressure fitting by a flexible inflating line. FIG. 5 shows a typical'one of these manifolds which comprises a coupling 44 mounted near the deck and having a spacer 45 in which the pressure fittings F are mounted. The pressure fittings are normally enclosed and protected by a bull plug 46 which screws into the coupling 44 when access is not needed to the pressure fittings F. The bull plug 46 is of course easily removable to gain such access to the fittings F. The fittings are in turn connected to the upper ends of flexible pressure lines such as the

lines

50 and 51, any desired number of which can be housed in a single manifold structure, the

lines

50 and 51, and others, being centered in a urethane guide block of 49. By reference to FIGS. 1 and 2, the location of the bull plug which covers the manifold is referred to by the reference numeral 46. A protector pipe 52 extends downwardly beneath the manifold and enters the leg 18 at an entrance point which resembles the illustration in FIG. 8. The pipe 52 extends downwardly within the leg as shown in the heavy-dashed line in FIG. 1 and when it reaches a given elevation, which is also the elevation of the upper ends of the piling

sleeves

28 and 29, the pipe 52 exits from the leg 18 as illustrated in FIG. 8 and branches out into a number of branch protector pipes which are labelled 53, 54, 55, and 56in FIG. 9. In the present illustration, the main protector pipe 52 is a four-inch inside diameter, whereas, each of the branch protector pipes 53 through 56 inclusive is a one-inch diameter pipe, the reduction being possible because of the fact that although the main protector pipe contains a large number of flexible lines, each branch protector pipe contains only one flexible line. The type of branching is generally illustrated in FIG. I and FIG. 2 at the branching levels labelled 57 and 58, the illustration in FIG. 9 is typical of the branching occurring at the point 58 since the lower end 59 of the main protector type 52 in FIG. 9 is plugged. It is quite possible to run the branch protector type either inside ofa platform leg, or else outside of it. For instance, FIG. 10 shows a crosssectional view of a protector-pipe routing which is the type of routing which would be seen at the line 10-10 in FIG. 1.

Another main protector pipe 60 runs from a manifold assembly 61 downwardly and into the leg 16 through an entrance point 62. The main protector pipe 60 has branch pipes which exit from the leg at the level 63, but the main protector pipe continues on down the leg to a point 64 which is also an exit point. FIG. 10 shows a cross-section in which the main protector pipe extends downwardly between the inner and the outer leg members l1 and 12 in order to achieve excellent mechanical protection of the protector pipe 60, and at the exit level 64 it branches in the manner generally shown in FIG. 10 into four

branch protector pipes

65, 66, 67, and 68, and these branch protector pipes are also further protected by being housed for most oftheir lengths within the annulus space between the

leg members

11 and 12. Although this structure provides optimum protection of the protector pipes themselves, it is also relatively difficult and expensive to build, and therefore, FIG. 12 is proposed as a less expensive alternative which on a practical basis will probably prove quite satisfactory. In the construction illustrated in FIG. 12 the protector pipe 60 exits from within the leg 12 in a manner generally illustrated by FIG. 8 at the level 63 as shown in FIG. 1 and travels downwardly on the outside of the member 12 to the level 64 at which it branches into the four

branch protector pipes

65, 66, 67, and 68 which extend around the outside of the leg member 12 and then enters the respective sleeves, such as the

sleeves

24 and 25, in the manner illustrated in FIG. 11.

As illustrated in FIG. 11, a semi-circular pipe housing 70 is welded to the outer surface of the guide member 25 and supports the pressure fitting 39 as an initially fabricated part of the piling guide sleeve construction. The housing 70 is provided with a threaded entrance 71 into which a length of the protector pipe 66 can be screwed after the flexible pressure line 72 has been screwed at its coupling 73 into the mounted pressure fitting 39. Thus, the illustrated flexible pressure line 72 in FIG. 11, as well as all other flexible lines such as the

lines

50 and 51 shown in FIG. 5, are fully enclosed in protective rigid pipe all the way from the packer to the uppermost pressure fittings F which can be pressurized selectively by pressure from the pump P using appro priate coupling hoses such as the hose H as shown in FIG. 2.

In connection with the pressure lines extending from the manifold 75 to the packers which are contained within the piling

sleeves

26 and 27 at the lower end of the leg 20, this pressure system includes a main protector pipe 76 which travels downwardly along the leg 12, inside the leg in this illustrative example, and then extends outside as shown at the reference numeral 77 over to the leg 20 and downwardly as illustrated at 78 within that leg, since the leg does not extend up to the surface. It is to be understood that the

protector pipes

76 and 78 can be run down the outside of the legs. The illustrations in FIGS. 8 and 9 are of course also typical of the manner in which the protector pipes change from a main protector pipe 78 to branch protector pipes at the exit levels 79 and 80. In this type of construction, it is desirable to weld the pipe 77 to the brace member 22 appearing just below it in order to prevent the pipe from being accidentally displaced.

This invention is not to be limited to the exact embodiments illustrated in the drawings, for obviously changes may be made therein within the scope of the following claims.

I claim:

1. In an off-shore marine structure of the type having a platform supported by one or more legs extending beneath the surface of the water and resting on the bottom of the sea and said legs having piling guide sleeves shaped to receive piles driven therethrough into the bottom, and said platform having fluid pressure supply means for selectively inflating the individual packer means in the sleeves to seal the annulus between each sleeve and its pile, improved means for coupling said pressure supply means with each of said packer means, comprising:

a. rigid main protector pipes extending down each platform leg to branching points at levels where packer means are located beneath the surface in the sleeves;

b. rigid branch protector pipes branching out at said branching point levels from each main protector pipe and extending therefrom to the inflatable packer means in the sleeves at that level;

c. manifold means in the vicinity of said pressure supply means and coupled to each main protector pipe at a level above the water surface; and

d. a flexible pressure line attached to each packer means and extending through a branch protector pipe and through a main protector pipe and to said manifold means, and each flexible line including means for coupling said pressure supply means to it.

2. In a structure as set forth in claim 1, wherein the sleeves on each leg each have plural packer means respectively located at different branching points for sealing the annulus between the sleeve and the pile at spaced different levels, said improvement further comprising said main protector pipes extending down to said several packer levels, and said branch protector pipes branching out from the main protector pipes at said different levels and extending to the packer means located thereat, and said flexible pressure lines being routed in said protector pipes and said manifold means.

3. In a structure as set forth in claim 1, wherein said protector pipe comprising rigid pipes welded to said platform for support and extending inside each leg to exit at a branching point level and then emerging from the leg and extending to the respective packers at that level.

4. In a structure as set forth in claim 1, wherein said platform having some legs made with double concentric walls, and said main protector pipes extending downwardly in the legs between the concentric walls and joining branch protector pipes at the levels where packers are located, and the branch protector pipes at each level extending circumferentially of the leg between the concentric walls to exit points adjacent the respective packers to which they are attached.

5. In a structure as set forth in claim 1, wherein said flexible pressure lines comprising flexible tubing with coupling fittings at each end respectively coupled to one of said packer means and to one of said manifold means.

6. In a structure as set forth in claim 1, wherein each manifold means being located near the top of the platform in the vicinity of the pressure supply means, and having means for accessibly supporting the coupling means of all of the flexible lines which enter the manifold means, and means for covering the manifold means to protect the pressure line couplings located therewithin.

Claims

1. In an off-shore marine structure of the type having a platform supported by one or more legs extending beneath the surface of the water and resting on the bottom of the sea and said legs having piling guide sleeves shaped to receive piles driven therethrough into the bottom, and said platform having fluid pressure supply means for selectively inflating the individual packer means in the sleeves to seal the annulus between each sleeve and its pile, improved means for coupling said pressure supply means with each of said packer means, comprising: a. rigid main protector pipes extending down each platform leg to branching points at levels where packer means are located beneath the surface in the sleeves; b. rigid branch protector pipes branching out at said branching point levels from each main protector pipe and extending therefrom to the inflatable packer means in the sleeves at that level; c. manifold means in the vicinity of said pressure supply means and coupled to each main protector pipe at a level above the water surface; and d. a flexible pressure line attached to each packer means and extending through a branch protector pipe and through a main protector pipe and to said manifold means, and each flexible line including means for coupling said pressure supply means to it.