US2883141A

US2883141A - Blowout preventer

Info

Publication number: US2883141A
Application number: US663721A
Authority: US
Inventors: John P Oliver
Original assignee: Cameron Iron Works Inc
Current assignee: Cooper Industries LLC
Priority date: 1957-06-05
Filing date: 1957-06-05
Publication date: 1959-04-21
Anticipated expiration: 1976-04-21

Description

April 21, 1959 J. P. OLIVER 2,833,141

BLOWOUT PREVENTER Filed June 5, 1957 3 Sheets-Sheet 1 /0/7/7 F. O// Ver INVENTOR.

A fro/WV: rs

April 21, 1959 J. P. OLIVER BLOWOUT PREVENTER r. E 2 em v N a YT m m hm (4. 7 A 0v 7 w m A e P s 4 d F jiled June 5, 1957 April 21 1959 R OLIVER 2,883,141 BLOWOUT PREYENTER Fil'ed June 5, 1957 3 Sheets-Sheet L3 JO/W? 1 O/n/er BYQ)WW Patented Apr. 21, 1959 l 2,883,141 BLowoU'r PREVENTER Oliver, Houston, Tex., assignor to Cameron Iron l Works, Iric., Houston, Tex.

Application Tune

5,1957, Serial No. 663,721

*8 Claims. (Cl. 251-1) This invention relates to blowout preventers for sealing about a pipe at the head of an oil or gas well. More particularly, it relates to improvements in rams for such 'preventers.

In a blowout preventer of the type contemplated by thepresent invention, a pair of rams are movable longitudinally within guideways of the body of the preventer which intersect opposite sides of a bore therethrough. These rams carry sealing strips at least a portion of which is fiowable material so arranged thereon as to seal about a pipewithinthe bore and with one another as well as Fig. 1 is a view, partly in section and partly in elevation, of a pipe disposed within the bore of a body of a blowout preventer having rams constructed in accordance with the present invention; Fig. 2 is a perspective view of one of such rams removed from its guideway within the body of the blowout preventer; Figs. 3 to 5 are partial plan views of the inside of the preventer, and showing sequentially the movement of the rams into fitted position about the pipe within the bore of the preventer body;

with respect to theguideways when each is moved into I extended position across the bore. For this purpose, the inner end of each rarn body is conventionally provided witli 'arecess extendinglaterally thereacross and a groove extending transversely of the recess for fitting about a pipe,and the sealing strip carried thereby includes a portion received within such recess and having a groove therein substantially aligned with the groove in the inner end of the ram.

The pipe which is to be sealed may be of small diameter in comparison to the bore of the preventer body. As' 'a result, the pipe may be considerably out of line with the axis of the grooves in the rams for fitting thereabout. It has heretofore been proposed to provide the rams with interfitting partsfor guiding the pipe into alignment with the grooves as the rams are extended into the bore.

Fig. 6 is a perspective view, similar to Fig. 2, of another embodiment of a ram constructed in accordance with the present invention; and

Fig. 7 is a top plan view, on a smaller scale, of the ram of Fig. 6

Referring now in detail to the above-described drawings, the blowout preventer illustrated in Fig. 1, and designated in its entirety by reference character 10, comprises a body 11 having a bore 12 therethrough and a pair of cylindrical guideways 13 intersecting opposite sides of the bore.

Fittings

14 and 15 may be sealably connected above and below the preventer body 11 by means of bolts 16 and seal rings 17. These fittings may comprise suitable parts of a well head, as well known in the art. It will be noted, however, that each of these fittings is provided with a bore therethrough in substantial alignment with the bore of the blowout preventer body for receiving a pipe 18. A A ram 19 of cylindrical cross-section is mounted. in each of the guideways 13 for movement between the re tracted position of Fig. 1 outwardly across the bore for These parts have comprised tapered wings and corre- CiThiso'bject, as well as other objects, advantages and features of the invention, which will be more apparent upon/a consideration of the written specification, the attached claims and the annexed drawings, are accomplished by means of a ram having flat faces on its inner end and a sealing strip portion carried in the ram recess and having a' face so formed as to cooperate with a similar face on thezsealing strip of the opposite ram in guiding the pipe into the pipe grooves in each ram. Thus, the upper and lower edges of the face of each sealing strip at each side of the groove therein are fiat and parallel to the upper and lower edges of the corresponding face of the other sealing strip and form oppositely disposed acute angles with respect to a plane perpendicular to the longitudinal axis of the ram body. The portions of the face of the sealing strip portion on opposite sides of the groove thereused throughout to designate like parts:

fitting about the pipe When the rams are so extended, in a manner to be described more fully hereinafter, the annular space between the pipe and the well beneath the rams will be sealed off.

Each of the rams is moved inwardly and outwardly of the bore by suitable means which may include a stem 20 threadedly connected to the outer end of the ram and having an actuating part 21 extending outwardly of a bonnet 22 connected by bolts 23 across the outer end of the guideway for the ram. This stem 20 is journaled for rotation within an outwardly extending boss on the bonnet and is held against longitudinal movement by a collar 24 disposed between an internal shoulder 25 on an opening 26 through the bonnet and a thrust ring 27 fixedly disposed within an enlarged diameter portion at the inner end of said opening. The lower end of each ram is provided with a groove 31 slidable over a pin 32 in the guide way to prevent rotation of the ram within its guideway and thereby cause it to be moved longitudinally of said guideway upon rotation of the stem 20. Of course, rotation of the ram within its guideway may be prevented by a ram and guideway of other than cylindrical shape.

As shown in the sectional portion of Fig. 1, the stem may be sealed by a packing 28 which is held in place within the opening 26 through the boss portion of the bonnet by a gland 29 and a cap 30 disposed over the gland and threadedly connected to the outer end of the bonnet.

With reference now to the novel construction of the blowout preventer ram 19, it will be seen from Fig. 2 to comprise an elongate, cylindrical body 33 of relatively rigid material connected to the stem 20 and having a recess 34 extending laterally across the inner end thereof. Grooves 35 are formed in the inner ends of the body transversely of the body recess. A sealing strip 36 at least a major portion of which is fiowable material, such as rubber, is carried by the ram body and includes a portion 37 received within the recess 34. The upper and lower edges of this sealing strip portion areformed by retainer plates of relatively rigid material mamas ate the body and flowable material of such portion. Grooves 35a in each of the retainer plates and a groove 38 in the flowable material of the sealing strip portion 37 are substantially aligned with the grooves in the ram body 33 These .groovesv are of such radius as to fit closely about approximately one-half the circumference of the pipe 18 so that the pipeis adapted tobe surrounded by the opposed rams.

As is conventional in the prior art, this sealing strip 36 also includes portions 39 extending longitudinally from .the laterally extending portion 37 along both sides of the ram body 33, as indicated in Fig. 1, and another portion 40 extending transversely across the ram body between the outer ends of portions 39. More particularly, the last-mentioned laterallyextending portion 40 is so spaced from the inner end of the ram that it seals with the upper side of the guideway 13 of the preventer when the ram is fitted about the pipe. Thus, the sealing strip 36 forms a complete seal with the preventer body so that with the portion 37 of the sealing strip of each ram engageable with said portion of the other ram and fitted about the'pipe, the annular space about the pipe and below the rams will be sealed oif, as previously men tioned. When the rams are so extended, well pressure beneath the sealing strips 36 will find access to the outer end of the rams for aiding in holding them in tight sealing engagement with the pipe and with one another.

As shown at 41 and 42, in Fig. 2, the faces of the inner ends of the ram body 33, at opposite sides of grooves 35 and respectively above and below the recess 34 and the faces 41a and 42a of the adjacent retainer plates, are fiat and form oppositely disposed acute angles with respect to a plane perpendicular to the longitudinal axis of the ram body. That is, with reference to the rightmost ram of Figs. 3 to 5, it will be understood that the faces 41 and 41a transcribe acute angles with respect to such a plane in a counterclockwise direction, while the

faces

42 and 42a transcribe acute angles with respect to such a plane in a clockwise direction. As can also be understood from Figs. 3 to 5, the faces of the leftmost ram are also flat and parallel to corresponding

faces

41 and 41a and 42 and 42a on the rightmost ram for cooperation in guiding the pipe 18 into fitted position between the grooves in the ram body and sealing strip. Preferably, the aforementioned faces lie in planes parallel to the axis of the grooves in such body. In this manner, the rams are identical and interchangeable with respect to one another. 7

With reference to Fig. 2 as well as Figs. 3 to 5, the flat faces of the ram bodies extend parallel to the adjacent edges of retainer plate faces 41a and 42a, respectively. As best shown in Fig. 2, the flowable material portions of the face of the sealing strip portion 37 on opposite sides of the groove 33 are contoured for uniform sloping outwardly from the groove in oppositely disposed and increasing angularity with respect to the axisof the groove. Thus, these faces of the sealing strip 37 will conform to one another as the interfitting faces on the inner end of the ram bodies are moved toward one another.

More particularly, in the open position of the rams, the flowable material of the sealing strip of each ram projects slightly outwardly from the

faces

41 and 42 of the ram body so as to provide an excess of flowable material for initial engagement with the flowable material of the sealing strip of the other ram and deformation into sealing engagement with the pipe and the guideway of the preventer. This outwardly projecting portion of the sealing strip is confined above and below by the retainer plates 43 whose fiat faces 41a and 42a terminate at their inner ends substantially adjacent the upper and lower edges of the face of the flowable material of the sealing strip portion 37. As well known in the art, this arrangement prevents flowing of the flowable material betweenthe faces '41 and 42 of the carrier as it is dis- 4 torted. Although such an arrangement is preferred, it is contemplated that the retainer plates maybe eliminated.

The manner in which the pipe 18 is guided into position between the grooves in the rams is illustrated in Figs. 3 and 4. As indicated in Fig. 3, one of such rams (the leftmost) may be first moved inwardly across the bore 12 through the blowoutpreventer body, and the other ram (the rightmost) then moved into such position. Alternatively, of course, both rams may be moved inwardly simultaneously. At any rate, the flat faces of the retainer plates of the sealing strip portion on each ram body cooperate with one another, as best shown in Fig. 4, so as to guide the pipe 18, which m'ay-b'eout of alignment with the bore, as indicated in Fig. 3, into a position in which said pipe is substantially axially aligned with such bore.

As in the ram embodiment above-described, the ram 44 shown in Figs. 6 and 7 includes a ram body having a recess 51 extending laterally across the inner end thereof. A'sealing strip 36 at least aportion of which is flowable material is carried by the ram body and includes a .portion 37 received within the recess 51. A groove 52 is formed in the inner end of each of the retainer plates transversely of the recess 51. This sealing strip portion includes a pair of retainer plates 46 of relatively rigid material. This portion of the strip is also .provided with a groove 38 in the flowable material thereof substantially aligned with the groove 52 in the retainer plates. These grooves are, of course, curved to a radius for fitting about a pipe within the bore of the blowout preventer.

Flat faces 47 and 48 on the inner ends of the retainer plates at opposite sides of groove 52 form oppositely disposed acute angles with respect to a plane perpendicular to the longitudinal axis of said body. Thus, in this respect at least, the retainer plates 46 correspond to the retainer plates 43 of the Figs. 1 to 5 embodiment. On the other hand, the faces 50 on the inner end of the ram body 45, above and below laterally extending recess 51, are disposed parallel to such plane and thus differ from faces 41 and 42 on the body of the otherem bodiment.

As can be seen from Fig. 6, thesealing strip -36, and especially portion 37, is substantially identical to the strip of the previously described ram embodiment. Obviously, the ram 44 could be used in a blowout'pre'venter construction such as shown in Fig. 1. Also, it will be understood that oppositely disposed rams of this construction would function to guide a pipe into position in substantially the same manner as above described in connection with Figs. 3 to 5, except, of course, that the body would play no part in the guiding operation.

The ram body is provided with an "enlarged groove 53 on its inner end transversely of the recess S'Lth'ere'in to receive an annular boss 54 on each retainer plate 46. As can best be seen from Fig. 7, the inner portion :of each boss forms a continuation of groove 52, while the outer portion thereof, which is curved concentrically of groove 53, is normally disposed "inwardly of such groove. Thus, as the retainer .plates of the ram are moved 'into abutment with similar parts on an oppositely disposed ram, the plates are permitted to move inwardly a limited amount.

It is contemplated that the assembly comprising sealing

strip portions

37 and 39 and retainer plates may be replaced by another assembly differing only in the size of

grooves

38 and 52, whereby various sizes *of pipe may be sealed about without the necessityof changing the body. The large groove 53 in the carrier enables a wide range ofpipes to be accommodated by the interchangeable assemblies.

From the foregoing it will be seen "that this invention is one well adapted to attain allof "the 'ends -andobjec'ts hereinabove set forth, together with otherrad;

vantages which are obvious and which are inherent to the apparatus.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The invention having been described, what is claimed is:

l. A blowout preventer, comprising a body having a bore therethrough and a pair of guideways therein intersecting opposite sides of the bore, a ram mounted in each of said guideways for movement inwardly and outwardly of the bore, the inner ends of said rams having a recess formed laterally thereacross, a sealing strip at least a major portion of which is flowable material carried by each ram including a portion received in the recess thereof, and grooves extending transversely of the recess in each ram and the sealing strip portion received therein for fitting about a pipe within the bore, the faces of each ram on the inner end thereof above and below said recess and on opposite sides of the grooves therein being flat, and the upper and lower edges of the face of each of said sealing strip portion at each side of the groove therein being flat and parallel to the upper and lower edges of the corresponding face of said other sealing strip and forming oppositely disposed acute angles with respect to a plane perpendicular to the longitudinal axis of the ram so as to guide said pipe into said grooves as said rams are moved inwardly and seal about the pipe and with respect to one another.

2. A blowout preventer ram, comprising a body of relatively rigid material having a recess extending laterally across one end thereof and grooves in said one end of the body disposed transversely of the recess, the faces of the body on said one end thereof above and below said recess and on opposite sides of the grooves therein being flat, and a sealing strip at least a major portion of which is flowable material carried by said ram and including a portion received in said recess and having a groove formed in the face thereof in substantial alignment with said grooves in the body, the upper and lower edges of said face of the sealing strip portion on opposite sides of the groove therein being flat and forming oppositely disposed acute angles with respect to a plane perpendicular to the longitudinal axis of the body.

3. A blowout preventer ram of the character defined in claim 2, wherein the flat faces of the body extend parallel to the upper and lower edges of the sealing strip faces.

4. A blowout preventer ram of the character defined in claim 2, wherein the upper and lower edges of the sealing strip faces are formed by retainer plates of relatively rigid material intermediate the body and the flowable material of the strip portion.

5. A blowout preventer ram of the character defined in claim 4, wherein the flat faces of the body extend parallel to adjacent edges of the retainer plates.

6. A blowout preventer ram, comprising a body of relatively rigid material having a recess extending la'terally across one end thereof and grooves in said one end disposed transversely of the recess, the end faces of said body above and below said recess and on opposite sides of the grooves lying in planes perpendicular to the longitudinal axis of the carrier, and a sealing strip carried by the body, said strip including retainer plates of relatively rigid material received in spaced apant relation within the recess of the body adjacent the top and bottom thereof, and a portion of flowable material received between the retainer plates and having an end face with its upper and lower edges being confined by the adjacent edges of the end faces of the retainer plates, said sealing strip being removable from the body recess and having a groove therein inwardly of the grooves in the body, and the faces on the inner end of each retainer plate being flat and forming oppositely disposed acute angles with respect to a plane perpendicular to the longitudinal axis of the body for extension outwardly beyond the end faces of the carrier on opposite sides of the grooves therein.

7. A blowout preventer of the character defined in claim 6, wherein each retainer plate has an annular boss received within and having an outer surface formed concentrically of a groove in the body, said bosses being normally spaced outwardly of the groove to permit limited inward movement of the retainer plates.

8. For use in a blowout preventer ram, a sealing strip of flowable material including a laterally extending portion having a transverse groove formed in the face thereof, the portions of said face on opposite sides of the groove being contoured for uniform sloping outwardly from the groove in oppositely disposed and increasing angularity with respect to the axis of the groove.

References Cited in the file of this patent UNITED STATES PATENTS 2,090,206 King Aug. 17, 1937 2,188,141 Abercrombie Ian. 23, 1940 2,194,255 Allen Mar. 19, 1940 2,194,256 Allen Mar. 19, 1940 2,322,269 Allen "a June 22, 1943 2,527,068 Murray Oct. 24, 1950