US 3468132 A
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Description (OCR text may contain errors)
p 1969 G. H. HARRIS 3,468,132
PLATFORM LEG PACKER Filed March 1, 1967 s Sheets-Sheet 1 INVENTOR Glen H. Harris ATTOR NEYJ FIG.I.
Sept. 23, 1969 G. H. HARRIS PLATFORM LEG PACKER 3 Sheets-Sheet 2 Filed March 1, 1967 INVENTOR Glen H. Harris ATT! )RNInYS" Sept. 23, 1969 G. H. HARRIS 3,468,132
Filed March 1. 1967 3 Sheets-Sheet 3 FIG 5 mvewron Glen H. Horns 2 2.1%
T \\\v 8 An (ANNE 2 -N wmwwwwwwwmmmummnm"mu-M f w m u 1 D 0 8 b A ORNFJYS 3,468,132 PLATFORM LEG PACKER Glen H. Harris, Arlington, Tex assignor to Oil States Rubber (10., a corporation of Texas Filed Mar. 1, 1967, Ser. No. 619,749 Int. Cl. EOZb 17/00; B631; 21/50 US. Cl. til-63 7 Claims ABSTRACT OF THE DISCLGSURE A packer assembly for sealing the annulus between driven pilings and skirt guides through which they pass, the guides being located at the bottoms of marine drilling platforms secured by means of the pilings to the floor of the sea, and the annulus between the skirt guides and the pilings being poured full of grout above the packers when the latter are set after the pilings have been driven.
This invention relates to novel annular packer assemblies which are each secured to the lower inside periphery of a guide sleeve of large diameter through which a large-diameter steel piling is driven, for example, for the purpose of securing a stable platform structure to the bottom of the sea. When the pilings have been driven, the packers are inflated by compressed fluid to seal the sleeves to the pilings and support a column of concrete poured therebetween while it hardens. The concrete column is often quite high, perhaps eighty feet, and therefore the weight supported by the packer during hardening is very great.
It is a principal object of this invention to provide a rugged and highly reliable packer assembly to be fixed to and supoprted by the inner surface of a large diameter skirt guide sleeve, the proportions being rather different from ordinary packer assemblies because in the present structure the diameter of the packer is very much greater than its inflated thickness and than its axial length.
Another important object of the invention is to provide an assembly of the type described having means for protecting the resilient parts of the packer from physical damage while the piling is being inserted and driven through it into the floor of the sea.
A still further object of the invention is to provide means for anchoring the periphery of the inflatable bladder portion of the packer to the inner wall of the skirt sleeve in a way which will cause the bladder to lie flat thereagainst when deflated, but which will permit axial fore-shortening of the packer when it is inflated radially inwardly into contact with the driven piling.
Another important object of the invention is to provide anchor means for securing the bladder to the sleeve wall to provide continuous annular support for the bladder, when inflated, both from below and from above the inflated sealing engagement.
Another object of the invention is to provide a roughened engagement for the outer surface of the piling not only to increase the grip of the concrete thereon, but for the purpose of providing increased vertical support for the inner periphery of the inflated bladder where it contacts the piling, thereby increasing the capability of the packer to support the concrete column while it is hardenmg.
A further object of the invention is to provide a packer bladder especially designed and fabric-reinforced in an optimum way to support the column of cement while it is in the process of being poured and while setting.
Other objects and advantages of the invention will become apparent during the following discussion of the drawings, wherein:
FIG. 1 shows a typical marine drilling platform having legs extending to the floor of the sea, and having a plurality of skirt guides secured between the legs and housing pilings driven into the bottom of the sea to anchor the platform thereto;
FIG. 2 is an enlarged cross-section taken along line 2-2 of FIG. 1, the right-hand portion of FIG. 2 illustrating the piling in elevation and showing a column of concrete poured between the piling and skirt guide above a set packer, and the left-hand portion of FIG. 2 showing the piling in cross-section and the packer noninflated;
FIG. 3 is a partial section taken along line 33 of the left-hand side of FIG. 2;
FIG. 4 is an enlarged view corresponding with the left side of FIG. 2, and showing the packer enlarged enough to illustrate the fabric reinforcement contained therein; and
FIG. 5 is a view similar to FIG. 4 but showing the packer inflated into set condition.
Referring now to FIG. 1 this figure shows a drilling platform 1 supported on a plurality of legs 2 between which reinforcing truss work is provided including horizontal members 3 and 4. These members also support skirt guides 5 which are disposed between the legs 2 of the platform near the bottom thereof. The water level is shown at W in FIG. 1 and the floor of the ocean is designated by the letter F. The skirt guides 5 and the legs 2 extend somewhat below the floor level P and are embedded in the mud at the bottom of the sea. The skirt guides 5 are transfixed by pilings 6 which are generally in the form of steel cylinders, for instance about three feet in diameter. The pilings 6 are introduced through upper flared openings 7 in the skirt guides 5, and are driven as far as possible into the bottom of the sea. When the pile driving operation has been completed the annulus between each piling and skirt guide is poured full of concrete which is then allowed to harden and thereby make a unitary structure of the skirt guides 5 and pilings 6.
Each of the skirt guides is provided at its lower end with a packer 8 which packs off the space between the internal periphery of the skirt guide 5 and the outer surface of the piling 6 so that when the cement is poured into the annulus between the pilings 6 and the skirt guide 5 the cement will not escape through the lower end of the skirt guide, but will be retained therein while it hardens. The cross-section shown in FIG. 2 illustrates on the left side the packer in unset condition, and the right side of FIG. 2 illustrates the packer inflated into set condition. The piling 6 is preferably provided with bands, or with a helix, of steel wire 10 which is welded to the outer surface of the piling to further toughen it and improve the grip both of the packer 8 and of the cement C against the surface of the piling.
As shown in FIGS. 2, 3, 4, and 5, the packer assembly includes an upper ring 12 and a lower ring 14, both of which are rigidly fixed, as by welding, to the interior surface of the skirt guide 5. The upper ring includes tapered lugs 16, which may also be in the form of a continuous ring, welded to the inner surface of the skirt guide at spaced intervals therearound and serving to deflect the piling 6 toward and through the center of the packer assembly to prevent it from snagging thereupon as it is being lowered through the skirt guide, preparatory to driving the piling. The upper ring 12 contacts the skirt guide 5 at 12a, but is spaced therefrom at 12b. The ring is also provided with a recess 12 which serves to anchor the rubber portion to be hereinafter explained. The lower ring 14 is also arranged to contact the skirt guide at 14a, to be spaced from it at 14b and to have a recess at 14c to receive an anchor the lower end of the rubber member as will be described hereinafter.
The rubber packer 8 can best be seen in FIGS. 4 and 5 which show that it comprises a somewhat distorted toroidal bladder 2t) having a spud 22 extending through its outer surface and connecting to tubing T as can be seen in FIG. 2, which tubing extends to a source of fluid pressure (not shown). The tubing T is protected by a shield 5a which is attached to the outer surface of the sleeve 5. The tubing and spud serve to inflate the bladder when the packer is to be set, and the latter is embedded and bonded into the rubber bladder in a manner well-known per se in the clutch tube art.
Referring again to FIG. 4, the bladder includes upper and lower annular strips 24 and 26 respectively, each of which has an enlarged bead, respectively labeled 28 and 30. The bead is preferably reinforced with a wire band, and the fabric 32 extends around the bead for reinforcement purposes and runs the full length of the outer periphery of the rubber member. After the fabric 32 passes around the metal rings in the beads 28 and 30, it extends around the inner surface of the bladder so that the entire rubber member is peripherally enclosed by this fabric. An additional fabric reinforcement 34 is located inside of the bladder and encompasses the latter without going around the beads or through the strips 24 or 26. Thus, the inner-fabric 34 reinforces the bladder in such a way as to prevent tearing apart of the two fabric layers 32 in the strip portions 24 and 26 as the result of high inflation pressures necessary to set the bladder during pouring of the cement between the skirt sleeve 5 and the piling 6. About 75 pounds pressure above the ambient hydrostatic pressure at the packer depth is typical.
It should be noted that the recess 120 in the upper ring member 12 is elongated in the axial direction of the skirt guide so that the strip portion 24 and bead 28 can slide vertically up and down within the ring 12 and thereby permit fore-shortening of the rubber assembly in the vertical direction when the bladder is inflated into the position shown in FIG. 5 against the piling 6. The present drawings do not show the bead 28 actually reaching the shoulder 12s, but it is to be understood that this shoulder provides a positive stop against which the head can rest in the event that a maximum weight of concrete is supported from above, the concrete C being shown at the right in FIG. 2. In other words, the weight of the concrete never permits the entire strip portion 24 to withdraw from the anchor ring 12 which supports it. The lower bead is supported in the recess 14c of the lower ring 14 without being permitted to slide therein. This lower ring assembly serves to anchor the bottom of the rubber member in place in such a way as to prevent the weight on the rubber packer from being supported by the spud 22 which comprises a relatively small tube extending through a hole 5b in the skirt guide 5, and is not intended to support substantial weight. Thus, the tube is firmly anchored at its lower end, but is slidably anchored at its upper end in the manner shown in FIGS. 4 and 5. When the packer is set, the rubber tube portion 20a overlies the annular wires 10 which are welded to the surface of the piling 6, and engagement with these wires tends to discourage vertical slumping of the inner periphery 26a of the bladder.
It should be noted that when the bladder is deflated, FIG. 4, the inner periphery 20a lies radially recessed with respect to the inner surfaces of the lugs 16 so that there is no tendency for the piling 6 or the wires 10 to snag upon, or perhaps damage, the inner periphery 20a of the packer rubber. In general, it is not intended that the packer be recovered for reuse, but rather that it remain with the cemented piling and skirt guide after the cement has hardened.
The present invention is not to be limited to the exact form shown in the drawings, for obviously changes may be made within the scope of the following claims.
1. A packer assembly for sealing the annulus between a piling and a surrounding guide sleeve having an inner surface to which the assembly is fixed, comprising:
(a) upper and lower ring members fixed within the sleeve and spaced axially thereof, and having anchor means;
(b) an inflatable annular bladder normally disposed substantially flat against said surface between said ring members, the latter members extending radially inwardly of the surface at least as far as the bladder when the latter is deflated;
(c) upper and lower peripheral extensions fixed to the bladder, and extending respectively above and below the bladder and being respectively secured in said anchor means, the upper extensions slidably engaging the anchor means of the upper ring member to permit limited withdrawal therefrom as the bladder is inflated toward the piling; and
(d) means for inflating the bladder against the piling.
2. In an assembly as set forth in claim 1, said upper and lower extensions of the bladder each comprising a strip attached at one edge to an axial end of the bladder and having an enlarged head around the other edge, and the beads extending into and being captivated by the respective anchor means.
3. In an assembly as set forth in claim 2, the anchor means on each ring member comprising a ring of lesser outside diameter attached to said member and spaced from the sleeve surface by about the thickness of the strip, and the ring having an annular recess in its diameter at a position adjacent to the supporting member and receiving the bead and preventing withdrawal of the strip from the anchor.
4. In an assembly as set forth in claim 3, the upper anchor ring and the associated strip being wide as measured axially of the sleeve, and the associated recess being wider in said axial direction than the bead, the bead being located high in the recess when the bladder is deflated and approaching the bottom of the recess as the bladder is inflated.
5. In an assembly as set forth in claim 1, said bladder comprising an annular approximately toroidal tube of resilient material, and in its deflated condition having inner and outer working faces lying substantially against said sleeve surface, said working faces being joined by arcuate end walls; said strips in the relaxed condition of the bladder lying flush with a cylindrical surface including the outer working face and said beads lying around the edges of the strips remote from the tube and extending radially inwardly beyond the inner surfaces of the strips; and reinforcing fabric embedded in the resilient material of the tube, in the strips and in the heads.
6. In an assembly as set forth in claim 1, the upper edge of the upper ring member being tapered upwardly and outwardly from the inner surface of the member toward the surface of the guide sleeve to deflect piling inwardly when being lowered through the assembly.
7. In an assembly as set forth in claim 1, said inflating means comprising a spud embedded in the bladder and extending through its outer surface, the sleeve having an opening to pass the spud, means attached to the 5 6 spud outside of the sleeve for introducing compressed 3,314,240 4/1967 Bardgette 6153.5 fluid thereinto, and shield means attached to the sleeve 3,315,473 4/ 1967 Hauber et a1. 6156.5 X
and overlying and protecting said introducing means.
DAVID J. WILLIAMOWSKY, Primary Examiner References Cited 5 J. KARL BELL, Assistant Examiner UNITED STATES PATENTS 1,875,835 9/1932 Watt 61-56 X 3,213,629 10/1965 Manning 6163 X 56