US2746710A - Blowout preventer and ram therefor - Google Patents

Description

" May 22, 1956 M. R. JONES BLOWOUT PREVENTER AND RAM THEREFOR 5 Sheets-Sheet 1 Filed 001:. 29, 1952 Wm N mm N E mm Q Q w) w k 9v N i Kw mw I \\\\\\\\k w fi A d NW N r J MN N MW WW QW Y \o mm WW ATTOE/YEY y 1956 M. R. JONES 2,746,710

BLOWOUT FREVENTER AND RAM THEREFOR IN V EN TOR.

ATTORNEY y 1956 M. R. JONES BLOWOUT PREVENTER AND RAM THEREFOR Filed Oct. 29, 1952 5 Sheets-Sheet 3 IN VEN TOR.

ATTORNEY y 2, 1956 M. R. JONES BLOWOUT PREVENTER AND RAM THEREFOR 5 SheetsSheet 4 Filed Oct. 29, 1952 INVENTOR.

A TTORNEY y 1955 M. R. JONES BLOWOUT PREVENTER AND RAM THEREFOR 5 Sheets-Sheet 5 Filed 001:. 29, 1952 Q q u mll QQN MN W w QNW QN Qmm QN INVENTOR.

ATTORNEY United States Patent-"O BLOWOUT PREVENTER AND RAM THEREFOR Marvin R. Jones, Houston, Tex., assignor to Petroleum Mechanical Development Corporation, Houston, Tex., a corporation of Texas Application October 29, 1952, Serial No. 317,490

13 Claims. (or. 251-2 Thisinvention relates to a valve or blowout preventer construction and particularly to the ram members thereof which are employed to closethe passage through the preventer body.

Blowout preventers are conventionally employed in connection with the drilling and operation of wells, such as oil and gas wells, and are ordinarily mounted on the upper end of a well casing in position to close olf the well bore in the event sudden increases in pressure within the well occur which would tend to cause blowouts of the well.

Blowout preventers conventionally include a valve body having a tubular passage registering with the bore of the well and complementary segmental valve members, commonly called rams, which are radially movable across the passage in end-abutting relation to close the passage. Such rams are ordinarily provided with. complementary recesses in their abutting end faces which are shaped to complement the shape of the exterior of the drill pipe or other well tool which is being operated in the well bore, so that. upon the appearance of conditions likely to lead to a blowout, the. rams may be closed tightly about the inner string to thereby seal the well bore against such a blowout. Ordinarily, the recesses in the ram faces are semi-circular to correspond to the usual circular exterior of. drill pipe or other pipe string extending into the well'. In. some cases, they may have poly onal faces as when necessary to close about polygonal surfaces of the Kelly joints of rotary drill strings. In still other cases where it is desired to provide a closure in. the well bore when no. tools are in the well, the abutting end faces. of. the ram may be substantially flat so as to be directly engaged entirely across their end faces. The latter form of ram is commonly termed a blind ram.

It will be understood, that blowout. preventers must ordinarily be designed to withstand often enormous. pressures and to form efiective seals. between the rams and about the well tools irrespective. oftheir shape, as even very' small leaks under the. very high pressures often encountered may result in; cutting-out and destruction of the. preventer which may be. accompanied by destruction of the. well and surrounding property and equipment. as well as great. hazard to personnel in. the vicinity of the well.

Since. the occurrence of: a. blowout. cannot: ordinarily be anticipated and blowouts, may occur at anytime while operations. are. being conducted in. a well, there obviously will. not. be time or opportunity to change rams to match the. shape of the particular well tool which may be in the well at the particular time; or: to. install blind rams when there are no tools in the. well. This: means: that a series of blowout. preventers: having different: shaped rams. must be included: in the. well head installation if complete pro.- tection under all conditions: is to be assured, an arrangement which necessarily greatly increases the. cost and complexity of such installations. Moreover, in many in- 2,746,710 Patented May 22, 1956 2v stances the pipe or other well tools may not be perfectly centered in the well when it is sought to close the rams about the tool and the rams must, therefore be provided with special centering devices or shapes which increase the cost and complexity of design of such rams.

Accordingly, the primary object of the present invention is to provide blowout preventers having ram construction which are of universal character, in that they are adapted to close about and form effective seals with well tools irrespective of their particular external shape or position and which may also serve as blind rams in the absence of well tools in the well bore.

An important object is to provide a blowout preventer ram which is self-adjustable to the shape of a well tool to be engaged thereby.

Another object is to provide a blowout preventer ram constructed of deformable resilient material, such as rubber and the. like, having metallic reinforcing inserts molded therein so as to be automatically arranged in the ram body in accordance with the deformations of the ram body in order to provide eifective reinforcement therefor under all conditions.

A more specific object is to provide a ram body constructed of deformable resilient material having molded therein a plurality of vertically disposed, spaced apart, parallel metallic reinforcing plates which are free to move and adjust themselves in accordance with the deformation of the ram body to thereby provide effective reinforcement irrespective of the final shape of the ram body.

Other and more specific objects and advantages of this invention will become more readily apparent from the following detailed description when read in conjunction with the accompanying drawings which illustrate several useful embodiments in accordance with this invention.

In the drawings:

Fig. 1 is a vertical sectional view of blowout preventer employing a ram construction in accordance with one embodiment of this invention, the view being taken generally along line 1-1 of Fig. 2;

Fig. 2 is. a transverse sectional view taken generally alonglineZ-Z of Fig. 1;

Fig. 3 is a perspective view, partly in section, of one of the rams illustrated in Figs. 1 and 2;

Figs-4, 5 and 6 are fragmentary top plan views of the blowout preventer rams illustrating their accommodation to well tools of different shapes;

Fig. 7 is a perspective view of another embodiment of a. ram construction in accordance with the present invention';

Fig. 8 is afragmentary vertical section illustrating the form of. deformation occurring upon engagement of the end faces of a pair of rams of the kind illustrated in Fig. 3, particularly when employed. as blind rams;

Figs. 9 and 10 are views similar to Fig. 8 showing nonengaged and: engaged positions, respectively, of another ram embodiment. in accordance with the present invention;

Figs. 11, 12 and 13 arefragment'ary top plan views of another ram embodiment having end faces shaped to effect centering of an initially off-center pipe and showing the. rams at several stages during closing about the p p 1 Fig. 14 is. a view similar to Figs. 11,, 12 and 13 illustrating the ram embodimentof the latter figures employed as blind rams and. showing the rams in position just prior toattaining the fully closed. position;

Fig. 15 is. a fragmentary vertical sectional view of another modification of blowout preventer and ram in accordance with this. invention;

Fig 16 is a view similar to Fig. 15. of an additional modification of blowout preventer construction in accordance with this invention.

Referring to the drawings and initially to Figs. 1, 2 and 3 thereof, there is shown a blowout preventer casing 20 of generally rectangular shape having a circular passage 21 extending vertically through the center thereof and adapted to register axially with the bore of well (not shown) when mounted in any suitable and generally conventional manner on a Well casing. (Not shown.)

Generally rectangular ram chambers 22-22 extend from diametrically opposite sides of passage 23. through casing 20. The outer ends of the ram chambers are closed by means of suitably shaped bonnets 23-23 which may be removably connected to the respective ends of the casing by any suitable and conventional means, as by bolts 24 extending through suitably apertured mating flanges or cars 25-45 mounted on the adjacent ends of the casing and bonnets. Sealing gaskets 26-46 may be installed between the engaging ends of the casing and the respective bonnets. Each of the bonnets has a longitudinally extending central stern passage 27 in which a stem 28 is mounted and extends from the exterior of each bonnet into the related ram chamber 22. Stems 23 are arranged for reciprocation in passages 27 in any conventional and well known manner, which do not form any part of the present invention. For purposes merely of illustration, screw threads 29 are shown on the stems for engagement in the usual way with a correspondingly threaded member in the bonnets so that rotation of the stems will cause the stems to reciprocate through the bonnets. It will be understood that the stems may be reciprocated by any other conventional means, as by hydraulic or pneumatic means, all as Well understood in the art. Packing 30, of any suitable or conventional form, is arranged between stems 28 and the walls of stem passages 27 to provide fluid-tight seals therebetween.

A ram, designated generally by the numeral 31, is slidably mounted in each of the ram chambers 22 for reciprocation relative to passage 21 by means of stems 23.

Each of the rams 31, illustrated in enlarged detail particularly in Fig. 3, comprises a block or body 32 composed of a deformable resilient material, such as natural or artificial rubber or like composition, of generally rectangular shape conforming generally to the cross section of the ram chamber. The rear or outer end of the ram has secured thereto a metallic head 33 of the same shape and dimensions as the rear end of body 32 so as to be circumferentially flush therewith, and is provided with a socket 34 in its outer end to receive an enlargement 35 mounted on the inner end of stem 28 to form an actuating connection between the stem and the ram.

The inner or forward end of each ram is provided with a flat end face 36 which, as illustrated, may be inclined downwardly and outwardly with respect to the end of the ram, but may be vertical if desired. The height or vertical thickness of ram body 32 may be made slightly less than the corresponding dimension of the ram chamber for purposes which will appear hereinafter. The width of the ram body will ordinarily be made such as to provide a snug sliding fit between the opposite sides 37 of the ram body and the adjacent side walls of chambers 23. The overall length of ram body 32 will ordinarily be made such that it may be retracted into chamber 23 entirely out of passage 21, as illustrated in the left-hand portions of Figs. 1 and 2. The upper face 38 of ram body 32 may be cut away on its forward portion 39 to reduce the level of this portion slightly below that of face 38 Molded or otherwise securely bonded within the resillent material composing ram body 32 are a plurality of flat metallic inserts 40 which are vertically disposed and arranged in parallel spaced-apart relation and which extend longitudinally from points slightly rearwardly of forward end face 36 to approximately the rearward end 1 of portion 39. Generally speaking, the length of inserts 40 will'be made such that when the rams are in fully extended positions, at least a portion of the inserts will extend into chambers 23. The vertical dimension of inserts 40 are preferably made substantially equal to that of chambers 23 so that the generally parallel upper and lower edges of the inserts will have a snug sliding fit with the upper and lower walls of chambers 23. As noted previously, the vertical height or thickness of ram body 32 is made somewhat less than that of chamber 23 and this thickness is further reduced at its upper end at portion 39. The inserts 40 will ordinarily be positioned in ram body 32 so that their upper edges will extend slightly above the upper surface of portion 39 while their lower edges will extend below the lower face of the ram body, as may best be seen in Fig. 3. The lower edges of inserts 40 are provided with integral elongated extensions or tongues 41 which extend rearwardly beneath the lower faces of the ram body and of head 33 and are free to move relative to these faces. Since, as noted, the lower edges of inserts 40 and tongues 41 extend beneath the lower face of ram body 32, they may serve as vertical spacers between the lower face of ram body 32 and the adjacent bottom wall of chamber 23 and by their laterally spaced relation form a plurality of channels 42 providing communication between passage 21 and the portion of chamber 23 at the rear of head 33 for purposes to be described hereinafter. The forward edges 43 of inserts 40 may be downwardly and rearwardly sloped, as shown, to provide a nose section 44 on the inner end of the ram which is generally triangular in vertical section with its base along the lower face of the ram body and which provides a mass of plastic material which is relatively unreinforced and will, therefore, deform and flow more readily in response to pressure as will appear hereinafter It will be understood that the lateral spacing of inserts 40 will be variable and will depend upon a number of factors. Generally speaking, the lateral spacing of the inserts will be such as to provide intervening sections of plastic material which will be strong enough to resist extrusion or blowing-out between the inserts by the pressures encountered while undergoing the requisite deformation and plastic flow for accommodation to the shape of the object to be sealed. This will necessarily involve consideration of a number of factors well understood by those skilled in the art and will be determined generally by the physical properties of the particular resilient plastic material employed, the pressures involved, the height of the inserts, and the vertical thickness of the intervening sections of the plastic material.

By means of the above-described construction the forward portions of the rams when urged toward each other, will engage an intervening object and by reason of their deformable and resilient character will readily accommodate themselves to the external shape of the object, particularly since the top, bottom and sides of the ram bodies are confined by the corresponding walls of chambers 22 and the rearward ends of the rams are confined by the heads 33 which urge the ram bodies toward passage 21. The reinforcing inserts will be generally longitudinally displaced in accordance with the deformation of the forward portions of the ram bodies and their forward ends will assume positions about the object corresponding generally in configuration to that of the object about which the rams are compressed, as may be readily seen, particularly in Figs. 4, 5 and 6. At the same time the vertical position and lateral spacing of the inserts will be maintained so that the ram body will remain strongly reinforced internally andby engagement of the upper edges of the inserts with the upper walls of chambers 23 against upward displacement by pressure from the well. Tongues 41 are free to work beneath the ram bodies and heads 33 to accommodate the longitudinal displace ment of the inserts as the rams are urged toward each other about the object. Channels 42 beneath the rams permit pressure from the well to flow into chambers 23 behind heads 33 and thereby aid in closing the rams'as '5 soon as the) first sealingengagement is made.between the forward ends of the rams. Channels 42 willalso, permit; escape of fluid which'zrnay become; trapped in the. ram chambers, behind heads 3,3,so that the mats maybe readily retractedjwhen desired. Under the pressures, exerted'in closing the rams about an object, the deformable material comprising the ram body and particularly that'tin n s portions 44' will be deformed and. eng geinplastic flow which will readily permit. the end facesof-the; rams to accommodate themselves to .theexteriorconfigurat-ion of the interveningobject and form a strong fluid-tight seal about the object. When thepressure is relieved and the rams retracted, they will readily return totheir original shape; The excess material provided inilose. 44, also constitutes a reservoir, in effect,; of suchmaterial which will compensate for wearing of the end faces of the. ram.

Fig. 4 illustrates the positions. ofthe rams and reinforcing inserts when therams are closed about a pipe 45 whichis centered in passage 21.- 1 Fig. 5, is a view showing how the inserts accommodatethemselves when sealing about pipe 45 when it iseccentrically',positionedwith. re-

spect to the axis of passage 21.. Fig. 6 illustrates therams closed about a non-round object, such as a conventional square Kelly joint 46 commonly used in rotary well drill- 111g. F t o;

As illustrated in the several figures, the inserts 40 in one ram of each pair will usually .be off-set or staggered laterally with respect to. those: of, the. other ram vso that the adjacent forward ends of the inserts will be non-registering to thereby provide additional flexibility in the abutting end faces of the rams.

Fig. 8, illustratesthe character of. the deformation occurring in the nose portions 44 of the rams when the latter are strongly compressed, the excess material-being thereby caused to flow into thick downwardlyrprojecting lip portions from. which excess material. may, by plastic. flow under pressure, move to fill any interstices or "irregularities in and about an intervening object. and iinthe ram chambers. Such excess "material will also beavailable to compensate for wear of the end faces of the rams.

Fig. 7 illustrates another embodiment of ram in which the ram body 47 is made generally cylindrical rather than generally rectangular as in the previously described embodiment. The metallic head 33a will be of similar generally cylindrical shape. The metal inserts 40a will be varied in height and their upper and lower edges suitably shaped, as shown, so as to conform to the cylindrical periphery of the ram body. It will be understood that such cylindrical rams are adapted for use in conventional types of blowout preventers having cylindrical ram chambers. These cylindrical rams will function in the same manner as those previously described.

Figs. 9 and 10 illustrate a modificationof the farms illustrated in Figs. 1 to 6 and 8. The modification consists in making the forward faces 36a of the rams vertical rather than forwardly inclined and providing recesses 43a in the forward edges 43 of inserts 40. With this construction, when the rams are forced into abutting relation, recesses 43a cooperate to form a lateral channel for the deformable resilient material constituting ram bodies 32 .through which the material may move readily in response are shown engaging a pipe 52 which is initially off-center with respect to the axis of passage 21. As the rams are urged toward each other about pipe 52, sloping walls 50 coast with the. pipe; and with each other ref ree the pipe toward. the central recesses 49 to thereby center the pipe between the rams. Fig. 12 shows the. rams partially closed with the pipe urged to a position slightly inadvance of the fully centered positon. In Fig. 13. the rams are shown fully closed about pipe 52. It will be understood that side, sections 5151 of the rams will become engaged before closure is complete and as the closingpressure on the rams is increased, plastic flow of the material. composing the ram bodies will urge wall 49-49 toward each other and about pipe 52 until a tight seal is formed about the pipe, the inserts 40 moving with the plastic flowto assume the general pattern shown in Fig. 13.

Fig. 14 illustrates the closing action of rams in accordance with the embodiment of Figs. 11 to 13. when employed as blind rams. As the rams are. urged toward each other, the plastic How of the ram material, resulting from engagement of side sections 51-51 will fill recesses 49-49 until the forward faces of the rams. are. in. sealing contact, throughout their entire areas, Fig. 14 showing the. compressed end faces slightly in advance of the fully closed position.

-Fig;. 15 illustrates another blowout preventer. construction in which ram body 32b has a vertical thickness such as to provide a snug sliding fit between the upper and lower walls of chamber 22. Inserts 40bhave their upper and lower edges substantially flush with the upper and lower faces of the. ram body and tongues. 41 of the. previouslydescribed embodiments are. eliminated. In lieu of channels 42' formed in, the previously described embodimentsbetween the lower face of the ram body and the bottom wall of chamber 23, channels 42a may be pro; vided in casing 20 extending from passage 21 through the lower wall: of chamber 23. tov a. point behind: the ram.

, Channels 4211 will serve the same function as channels 42 as, set forth inconnection with the earlier-described embodiments.

Fig. 16 illustrates a ram of the same form as ram.- 32 in a blowout preventer casing having no, channels corresponding to channelsv 42a. This, modification; may be employed in cases where pressure-relief channels are not found necessary.

As will be evident from the foregoing, the present invention, in its several embodiments, provides improved blowout preventer rams possessing a high degree of plasticity and deformability which enables the rams to form strong fluid-tight seals in a well bore about objects, such as well tools, having varied peripheral shapes, and which are provided with strong internal reinforcement means which, in effect, float within the material composing the ram bodies and are freely movable therein in conformity with the deformation of the rams as they are compressed about such objects. The inserts will thereby maintain their reinforcement function in all positions in resisting pressures which might otherwise cause deleterious extrusion or destruction of the ram bodies. The rams in accordance with this invention are, therefore, of universal character in their self-adjustability for sealing about objects of varied external configurations.

It will be understood that various other changes and alterations may be made in the details of the several illustrative embodiments and modifications herein disclosed within the scope of the appended claims without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent 1s:

1. A blowout preventer ram, comprising, a body com posed of deformable resilient material having an objectengaging face on its forward end, and a plurality of freefloating fiat metal plate members embedded in said body, said plate members being disposed in closely spaced-apart parallel relation substantially throughout the transverse section of said body and extending vertically substantially from the upper to the lower surfaces of said body and longitudinally thereof from points adjacent said face to points intermediate the ends of said body, the arrangement of the plate members being such that when said face is engaged with an object the plate members will remain in substantially parallel relation.

2. A blowout preventer ram as defined in claim 1, wherein said body is substantially rectangular in transverse cross-section.

3. A blowout preventer ram as defined in claim 1, wherein said body is substantially circular in transverse cross-section.

4. A blowout preventer ram as defined in claim 1, wherein said object engaging face is a generally plane surface extending transversely across' said forward end.

5. A blowout preventer ram as defined in claim 1, wherein said object-engaging face is a generally plane surface extending transversely across said forward end and is inclined forwardly and downwardly with respect to said forward end.

6. A blowout preventer ram as defined in claim 1, wherein said object-engaging face has'a vertically extending medial recess therein having forwardly and laterally sloping side walls merging at their outer ends into flat end sections adjacent the opposite side edges of said face.

7. A blowout preventer ram as defined in claim 1, wherein the forward edges of said plate members are inclined downwardly and rearwardly.

8. A blowout preventer ram as defined in claim 1, wherein the forward edges of said plate members are provided with inwardly extending recesses.

9. A blowout preventer ram as defined in claim 1, having a rigid metal head secured to the rearward end of said body.

10. A blowout preventer ram as defined in claim 1, having a rigid metal head secured to the rearward end of said body, the configuration of said head conforming to the transverse cross-sectional configuration of said body.

l1.A blowout preventer ram as defined in claim 1, wherein the rearward end of each of said plate members has elongated tongue portion extending rearwardly beneath the lower face of said body and movable with respect thereto.

12. A blowout preventer including a casing, a circular passage extending vertically through said casing and a pair of ram'chambers extending from diametrically opposite sides of said passage, 21 pair of rams slidably mounted in said chambers for reciprocation therein relative to each other across said passage, each of said rams conforming in cross-sectional shape to that of said chambers and constructed of deformable resilient material having an object engaging face on its forward end, a plurality of free-floating flatmetal plate members embedded in said body, said plate members being vertically disposed in closely spaced-apart parallel relation substantially throughout the transverse section of said body, said members extending longitudinally of said body from points adjacent said face to points intermediate the ends of said body and having a vertical height such that their upper and lower edges slidably engage the upper and lower walls of said chamber, the arrangement of the plate members being such that when said face'is engaged with an object the plate members will remain in substantially parallel relation, a rigid metal head secured to the rearward end of said body, and means connected to said head and extending to the exterior of said casing for reciprocating said ram.

13. A blowout preventer as defined by claim 12 wherein said plate members in one, of said rams are transversely staggered with respect to the plate members in the other of said rams.

References Cited in the file of this patent UNITED STATES PATENTS 1,713,3 4 v Arbon May 14, 1929 1,922,225 Wickersham et a1 Aug. 15, 1933 2,060,252 Shaffer Nov. 10, 1936 2,194,258 Allen Mar. 19, 1940 2,345,815 Harroun Apr. 14, 1944 2,609,836 Knox Sept. 9, 1952

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