US2690320A - Dual type blowout preventer - Google Patents

Description

Sept. 28, 1954 Filed April 28, 1952 D. u. SHAFFER ET AL 2,690,320

DUAL TYPE BLOWOUT PREVENTER 2 Sheets-Sheet l )V f4 ml FL' II'j array/7M3:

p 2. 1954 D. u. SHAFFER ET AL 2,690,320

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Patented Sept. 28, 1954 UNITED STATES PATENT OFFICE DUAL TYPE BLOWOUT PREVENTER Donald U. Shaffer and Arthur E. Wilde, Brea,

Caliii, assignors to Shaffer Tool Works, a corporation of California Application April 28, 1952, Serial No. 284,832

9 Claims.

This invention is a novel packer assembly and relates to packers used in blow-out preventers of the class, for instance, as shown in Schweitzer Patent No. 2,592,197 wherein shut off packer rams are inserted or removed by way of side windows in the valve shell.

Commonly, each ram has embedded in it a rubber or equivalent mass for engaging and making a fluid shut off through a pipe hole in the shell, or on the other hand is provided with a packer mass to make a complete shut off by diametrically abutting a like and opposed ram in a valve gate, as when there is no well working apparatus element in the shell. It is the broad intent of this invention to provide a packercarrying ram, for such valves, having embedded therein packing means having the double capacity of making a shut off when such an apparatus element is installed in the valve shell, or the other instance to make a complet shut oil when no such element is in place.

It is additionally an aim to provide a dual capacity ram packer involving packing means constructed of relatively movable packers one of which has a diametrical face to meet an opposed like face for making the complete shut ofi in the valve and the other of which has a concave area to abut and seal on an interposed work element (which is not here inventionally concerned) The invention resides in certain advancements in this art as set forth in the ensuing disclosure, and having, with the above, additional objects and advantages as herein developed, and whose constructions, combinations and details of means and manner of operation will be made manifest in the following description of the herewith illustrative embodiment; it being understood that modifications, variations, adaptations and equivalents may be resorted to within the scope, principle and spirit of the concluding claims.

Figure 1 is a top plan of a partly broken-away shell showing the shut olT rams in mutually meeting (closed) position in the absence of well working apparatus. Figure 2 is a central longitudinal section from top to bottom of a ram assembly with the packers in normal, idle position of the disclosed embodiment. Figure 3 is a top plan of a diametrical face (closing) ram packer. Figure 4 is a vertical, inside packer face elevation of the ram. Figure 5 is a central, longitudinal section of a modified form of ram embodying a fiuid-pressure-set diametrical face packer.

The depicted gate valve embodies a substantial, cuboidal shell 2 having top and bottom faces for attachment of desired well head fittings not shown. Large pipe holes 5 pass through the top and bottom, respectively, of the shell for passage of working apparatus, pipe or tool elements, for example. The holes communicate with a transverse chamber 6 in which is reciprocably guided a pair of opposed and cooperative closure or gate assemblies of which the left side gate assembly is shown in full and in diametrical shut off, or closed position, the right side gate being broken back for clarity.

Extending from the opposite ends of the shell are suitably motivated rods l having at their inner ends block heads Eh which slidably interhook into respective ram assemblies, now to be described. The right and left assemblies are substantially identical and the description of one will suffice, and it can be here stated that the assemblies move concurrently and oppositely.

The ram assembly includes a generally cuboidal block or body i6 slidable on the inner bottom face of the shell and having at its outer end a T-socket tilt and when the block It is thrust into its end of the shell by way of a window 2w, Fig. l, the rod head Th is embraced in the socket lllt with the consequence that the block is reciprocated by the activated rod; inwardly to close the rams and vice versa.

In the upper face of the block there is provided a suitably deep semicircular pocket lilo wholly open transversely on its center. On the top face of the pocket there is loosely supported a floating filler member ll of semicircular form in plan and concentric with the outer wall of the pocket and suitably spaced therefrom, Fig. 2. The inner face of the filler is suitably concaved at lie for conformable closure onto a more or less complementary apparatus element, as pipe or tool string, passing through the shell holes 5.

The bottom of the pocket i to is in the form of a shelf l 05. A feature of the invention resides in an upper body of suitable elastic packing material (rubber or a substantial equivalent) forming a packer unit consisting of a half-ring I2 interlocked in the space between the wall lflw of the ram block and the adjacent outer face of the interposed filler I I which is a half-ring in plan. This packer further includes a semicircular bumper portion lZb shown in Fig. 4 in inner end elevation and as integral with and depending from the half ring 52 down to the ram part lflp'. Therefore, the inner end faces I27, Figs. 1 and 4, reach from the inner shell surface engaging the upper lip of the half ring K? (Fig. 2) to the bottom part [021. Fig. 2 shows the bumper portion [22) extending straight back from the inner end face of the half ring [2 and integral therewith. The inner end faces I2 of this packer are substantially diametrical and are inwardly fulled as to the inner or radial ends of the filler ll so that rubber and not metal will land on the interposed apparatus element when in the shell hole 5. And this packer has the additional operation of pressing all around its lip-like part of the half ring 12 up against and sealing on the inner contiguous face of the top of the shellthat is, it seals its ram against leakage to the chamber 6. Fig. 2 shows the lip fulled slightly above the top of the ram and its filler II. The bumper portion 12b is interembedded with the near surface of the filler and with the shelf its as at 102' by which means the packer I2i2b is positively retracted with and by the ram as it opens. And still the lip part of the half ring 12 can be and is extruded by relative movement of the filler on the shelf.

Thus the packer 12-! 2b is the means for making a shut off if 'a tool or pipe element is in the pipe holes but cooperative with this there is provided a packer means which functions to make a complete shut off when there is no working element in said holes.

Therefore, between the shelf His and the bottom platform lap of the ram Hi there is provided a longitudinally extended recess 101" in which there is slidably fitted a diametrical bar 13 shown in Fig. 4 as meeting the near end faces of the upper packer i2, {2b. This bar has a frontal channel 30 from end to end in which is interlocked a complementary diametrical packer l4 which is fulled slightly inward from the front face of the bar for th purpose of insuring a good shut off contact with a like packer of the opposite ram packer in the valve shell-when the rams are closed, with no intervening work element in the shell.

The lower surface of the packer part [211 has sealing engagement with the bar 13 to prevent top leakage.

It is understood that various means may be employed for forcing the slidable bar in its closing direction or for yieldingly sustaining it in a normal, innermost, ready position. Fig. 2 discloses a substantial spring 55 expansively compressed between the back wall of the ram and the near face of the bar; a latch it serves to limit inthrust by the spring. Or, if preferred, the bar may have a packer piston 11 working in a fluid pressure chamber 18 in the ram body which may be supplied with pressure fluid by a suitable supply means (not shown) all as shown in Fig. 5.

What is claimed is:

1. A gate valve assembly including a pair of companion rams and a shell in which they are guided for relative reciprocation transversely of aligned, central top and bottom holes in the shell;

said rams each haVing relatively movable, independent dual purpose packers including parts of yieldable elastic material, one packer of each ram having a flat sealing face to meet and close against a like face of the opposing ram packer, and the other packer of each ram having a concave face to seal against interposed apparatus incidently in said shell holes for well hole work; one packer of each ram having a lip to seal on the shell and having engagement with the other packer of the same ram.

2. The assembly of claim 1; each said flat face packer being bodily retracted within a recess in its ram if arrested in the closing movement of said ram.

3. The assembly of claim 1; each said flat face packer part having means operative in its ram by motive pressure to engage and seal on an opposing corresponding ram part.

4. The assembly of claim 1; said flat face packers each having a piston operative in its ram, and means for forcing the pistons and their packers toward sealing position.

5. The assembly of claim 4; said means including a pressure fluid supply device.

6. The assembly of claim 4; said means including an expansion spring in each ram reacting to close its packer.

'7. The assembly of claim 1; each of said flat face packers including a transverse bar movably mounted in its ram and in the inner face of which said elastic material part is mounted to engage the corresponding part of the opposite ram.

8. The assembly of claim 7 and means in each ram for thrusting its packer bar bodily inward to sealing position.

9. A gate valve ram having independent packers movably mounted therein and relatively movable, a sealing medium interposed between said packers; one packer having a flat, transverse sealing face from side to side to make a complete shut off against a like packer, and the other packer having a concave face area for sealing on an interposed, axial object of corresponding contour and the sealing faces of the said packers having elastic packing material, and one of the packers having a sealing lip of elastic material for sealing on a shell in which the ram may be installed and having engagement with the other packer.

References Cited in the file of this patent Allen Mar. 19, 1940

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