US2237709A

US2237709A - Blowout preventer

Info

Publication number: US2237709A
Application number: US317229A
Authority: US
Inventors: Elmo O Lowe
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-02-05
Filing date: 1940-02-05
Publication date: 1941-04-08
Anticipated expiration: 1958-04-08

Description

April 8, 1941. 0 ow 2.237.709

' BLOWOUT PREVENTER Filed 1940 2 Sheets-Sheet 1 A WM Patented Apr. 8, 1941 UNITED STATES PATENT OFFICE 2,237,709 BLOWOUT PREVEN' IER Elmo 0. Lowe. Los Angeles, Calif.

Application February 5, 1940, Serial No. 317,229

16 Claims.

This invention relates to a device for use on oil and gas wells and relates more particularly to a control head or blowout preventer. A general object of this invention is to provide a simple, practical, blowout preventer that is positive and dependable in operation.

in drilling deep wells such as oil wells and gas wells, very high pressures are sometimes encountered in the earth formations penetrated by the well. This pressure often develops very rapidly and sometimes blows out aroundthe drilling tools, causing consider-able damage. Control devices lrnown as blowout preventers are provided at the upper ends of the well casings to control the high pressures that may suddenly develop during drilling operations. Ram type blowout preventers have gone into extensive use but considerable dililculty is encountered in providing eliective fluid-tight seals between the surfaces of the rains and the bodies of the devices. it has been the general practice to employ packing oi rubber, or the like, to seal between'the rams and the bodies. This rubber packing is not dependable and soon wears or cuts out, necessitating difilcult, time consuming repaciring operations.

Another object of this invention is to provide an effective blowout preventer in which dependable, iluid-tight seals are provided at the upper and lower surfaces of the rains without resorting to the use of rubber paclring, or the like.

another object of this invention is to provide a blowout preventer of the ram type, embodying novel means for providing effective, dependable seals at both the upper and lower sides oi" the rains.

iinother object of this invention is to provide a blowout preventer in which-the rams are tightiy brought against seats on the upper and lower walls of the body when they reach their sealing positions about the pipe to provide seals at the upper and lower sides of the rams.

Another object of the invention is to provide a blowout preventer of the character mentioned embodying novel expansible packing means on the rams inflated by fluid pressure to assure fluidtight seals about the pipe or object.

Another object of this invention is to provide a blowout preventer of the character mentioned that is simple and inexpensive to manufacture and that is compact and light in weight.

The various objects and features of my invention will be fully understood from the following detailed description of atypical preferred form and application of the invention, throughout which description reference is made to the accompanying drawings, in which:

Fig. 1 is a side elevation of the blowout preventer of this invention. Fig. 2 is .a top or plan view taken as indicated by line 2-2 on Fig. 1 with certain parts in horizontal cross section. Fig. 3 is an enlarged, fragmentary vertical detailed sectional View of the device showing the rams in the closed positions with the drill pipe removed. Fig. 4 is a horizontal detailed sectional view taken as indicated by line 4-4 on Fig. 3 showing the rams in open positions with the drill pipe removed. Fig. 5 is a fragmentary vertical detailed sectional view taken as indicated by line o -J on Fig. 3. Fig. 6 is an enlarged fragmentary vertical detailed sectional view taken as indicated by line t-B on Fig. i. Fig. 7 is a fragmentary vertical detailed sectional view taken as indicated by line 'l--l on Fig. 6, and Fig. 8 is an enlarged sectional view of one of the packing parts.

The blowout preventer of this invention may be said to comprise, generally, a body it to be conected with the well casing or other well equip-- went, a pair oi closure gates or rams ll oper able in the body iii, means it for moving the rams ii between their open and closed positions, and means ill for moving the rains laterally to seal with the interior of the body ill when the rams reach the closed positions.

The body it is a hollow structure adapted to be connected with the upper end of the well casing and serves to contain the closures or rams ii. The body it may be varied considerably in design and construction without departing from the invention. in the construction illustra'ted the body it has a central depending part it provided at its. lower end with a flange it for connection with the casing U, a head, or a valve on the casing. .iin internally threaded part it projects from the upper end of the body it to receive a casing section S. A central vertical opening ill extends through the body it and its proiectingparts it and it, and communicates with the well casing. The major portion of the body it has a transverse chamber or opening it intersecting the vertical opening H.

An access window or opening i9 is provided in a side wall of the body it to communicate with the opening it. The access opening I9 is closed by a cover or plate 2|]. The plate 20 may be removably secured to the body i I] by screws or bolts 2|. The inner side of the plate 20 is complementary to the opposing wall of the body Ill. The inner side of the plate 20 and the said opways 2| providedwith fiat upper and lower walls.

Raised annular seats 22 are provided on the upper and lower walls of the opening l8 in surrounding relation to the vertical opening l1. As best illustrated in Fig. of the drawinBs the seats 22 are finished and flat and are pitched to be in converging relation. The surfaces of the seats 22 are pitched laterally and in the case illustrated converge toward the closed wall 01' the body ||l having the guide way 2 I.

The closure gates or rams operate in the opening l8 between .the open positions illustrated in Fig. 4 where they are clear of the opening l1 and the closed position illustrated in Figs. 2, 3 and 5 where they may engage about a drill pipe P or other object extending into the well. The.

rams II are alike and are arranged in theopening |8 in opposing relation. In the case illustrated where the rams II are intended to seal about the pipe P the rams are semi-annular, having opposed vertical notches 23 in their inner sides for receiving or cooperating with the pipe P. The rams II are designed to move in the opening I8 with freedom and have flat, generally horizontal upper and lower sides. In accordance with the invention the rams II are supported to move toward and away from one another and to move laterally relative to the direction of the first named movement. Pairs of lugs 24 project laterally from the opposite sides of the rams adjacent the inner ends of the rams and have fiat upper and lower faces 25 which ride on the walls of the guideways 2|, The lugs 24 may have clearance with the side walls of the guideways 2| to permit free movement of the rams. Substantially central tail lugs 26 are provided on the upper and lower sides of the rams II to posing wall of the body l0 have horizontal guidethe like, some compressible and resilient. Dovetailed grooves 3| are formed in the inner faces of the rams H and in the walls of the notches 23 to receive the packing members 30, Themem-' bers 30 are spaced one above the other and extend from'adiacent the opposite sides of the rams. As illustrated in Fig. 5 of the drawings the packing members 38 have vertical branches 32 extending to the upper and lower sides of the rams When the rams II are in their closed positions the packing members of one ram tightly seal against the packing members of the other ram and the portions of the packing members in the notches 23 tightly pack about the pipe P. The packing members 38 may be solid or may be inflatable as illustrated. The means for inflating the packing members 30 will be hereinafter deride in grooves 21 in the upper and lower walls of the opening I8. The lugs 26 may project from the rear sides of the rams H, as best illustrated in Fig. 4 of the drawings and are free to move laterally in the grooves 21. The engagement of the lugs 28 in the grooves 21 stabilizes the rams and prevents tipping of the rams.

The upper and lower sides of the rams H are surfaces of the sealing ridges 28 are formed and finished to evenly bear against and seal with the converging surfaces of the body seats 22. As best illustrated in Fig. 5 of the drawings the sealing ridges 28 are pitched or convergent so that the rams may be said to be wedge-shaped in edge or face elevation. The sealing ridges 28 converge in the same direction as the body seats 22 and their surfaces are at substantially the same angle as the surfaces of the seats to evenly and efiectively seal with the seats when the rams are moved laterally. If desired, the upper and lower sides of the rams may be provided with packing instead of or in addition to the ridges 28.

The faces or inner sides of the rams II are preferably provided with packing to seal one with the other and to pack about the pipe P. In the form of the invention illustrated there are two spaced sealing members. 30 provided on the inner side of each ram The sealing members 30 may be formed of rubber, synthetic rubber, or

scribed. The inflatable members 30 illustrated have continuous grooves 3|) in their inner sides and longitudinal cavities or chambers 38 in their outer parts connected with the grooves 30" by ports 30.

The means l2 for operating or moving the rams II is operable to simultaneously move the two rams between the open and closed positions. The means I2 is a screw means including two spaced horizontal screws 33, The screws 33 extend longitudinally through the guideways 2| with clearance and the opposite ends of the screws are rotatably supported. One screw 33 has an end portion rotatably received in an opening 34 in the body wall and the other screw 33 has its inner end received in a similar opening 35 in the plate 20. Plugs 38 are removably threaded in the

openings

34 and 35 and are socketed'to rotatably receive the end portions of the screws 33. The other ends of the screws 33 are releasably coupled with stems 31.

Bosses

38 and 39 are provided on the body l0 and the plate 28 respectively and have openings 40 and 4| rotatably receiving the stems 31. vided with polygonal sockets 42 that receive correspondingly shaped end parts 43 of the screws 33 so that the screws turn with the stems 31. The stems 31 extend outwardly through suitable packing glands 44 on the

bosses

38 and 39 to project at the exterior of the device.

Collars 9 are fixed to the stems 31 to engage the adjacent ends of guideways 2| to hold the stems against displacement and endwise movement.

The screws 2 may be rotated or operated by an available or selected power means. In the construction illustrated sprockets 45 are fixed to the projecting parts of the stems 31 and a chain 46 operates over the sprockets so that the screws 33 may be simultaneously rotated. A second sprocket 41 is fixed to one of the stems 31 and a drive chain 48 operates over the sprocket 41. The drive chain 48 may extend to a remote drive means or power means for operating the blowout preventer.

Each screw 33 has a right-hand thread 49 and a lefthand thread 50 and internally threaded nuts 5| cooperate with the threads 49 'and 58. The nuts 5| are shaped and proportioned to be received between the lugs 24 on the sides of the rams The nuts 5| may be received in the guideways 2| with suitable clearance. It will be seen that rotation of the screws 33 causes cooperation between the threads of the screws 33 and the threads of the nuts 5| so that the nuts react against the lugs 24 to move the rams li toward or away from one another.

The means |3 for moving the rams laterally The stems 31 are prov racks 52 may be in the nature of webs connecting or joining the lower portions of the adjacent lugs 24. The upper sides of the racks 52 carry series of gear teeth 53.

The means I3 further include series of gear teeth 54 on the peripheries of the traveling nuts 5| engaging the adjacent rack teeth 53. The teeth 54 of the nuts 5| mesh with the rack teeth 53 at all times. Continued rotation of the screws 33 following the full closing of the rams II results in turning of the nuts H and the teeth 54 meshing with the teeth 53 shift the rams II laterally so that the sealing ridges 28 are wedged against the body seats 22 to provide seals at the upper and lower sides of the rams. The side wall of the guideway H in the body I8 is notched or relieved at 59 to receive the adjacent lugs 24 when the rams II are moved laterally. As best illustrated in Fig. 4 of the drawings the rams II are initially eccentric with respect to the vertical opening II, that is, the common horizontal center line of the rams II is offset from the vertical axis of the opening I1. During the above described lateral movement of the rams II the rams move toward positions where their notches 23 are concentric with the vertical axis of the opening ll. The eccentricity of the rams It and the pitch or inclination of the body seats 22 and the sealin ridges 28 are exaggerated in the drawings to better illustrate the invention.

The invention preferably includes means for lubricating the sealing surfaces of the rams II and the body III. The sealing ridges 28 of the rams II are provided with arcuate lubricant rooves 55. The grooves 55 preferably extend throughout the major portions of the ridges 28. Lubricant ports 58 extend vertically through the alls of the body and extend into the body parts I4 and I 6. The inner ends of the ports 58 are located so that they communicate -with the rooves 55 when the rams II are in the closed positions. Tubes or pipes 51 communicate with the outer ends of the ports 56 and extend to a common manifold 58. see Fig. 2. The manifold 58 may extend to a remote source of lubricant under pressure or to a' remote means for placing the lubricant in.the system under a high pressure. The lubricant supplied to the'arooves effectively lubricates the sealing surfaces of the bearing ridges 28 and the surfaces of the body seats 22 and aids in providing fluid tight seals.

Where the above described inflatable packing members 30 are employed the lubricating means may be employed to expand or inflate the members. As illustrated in Fig. 4 the ends of the lubricant grooves 55 join the ends of the grooves 30. Lubricant under pressure supplied to the grooves 55 as above described passes into the grooves 3ll and chambers 38* to actuate or expand the packing members; The-lubricant under pressure in the grooves 30 expands the memberscant under pressure in the chambers 38 expands the members 30 to have tight sealing engage-.

ment with one another and with the pipe P to positively prevent the leakage of well fluid and pressure.

' During the normal drilling operations the rams II are in their open or retracted positions where they do not interfere with the free passage of tools and equipment through the opening I'I. When high fluid pressures suddenly develop in the well the chain 48 is driven or operated by a con vient or available power means to rotate the screws 33. Rotation of the' screws 33 causes movement of the rams II toward'their closed positions. The rams l I move together until their sealing members 30 cooperate at the faces of the rams and until the sealing members engage about the pipe? or other object extending into the well. In practice the rotation of the screws 33 causes the nuts 5i to travel along the screws to bring the sealing members 30 into tight cooperation and into tight engagement with the pipe 1?. This tight cooperation of the rams I I and the engagement of the rams with the pipe P stops the inward movement of the rams. Continued rotation of the screws 33 when the inward movement of the rams is stopped results in turning of the nuts 51,; the nuts being unable to continue their travel along the screws. Upon turningoi. the nuts II. the teeth 54 meshing with the teeth 53 shift the rams II laterally or toward the notch 59. This shifting of the rams may be slight. However, it is suflicient to bring the faces of the sealing ridges 23 into tight sealing engagement with the sur faces of the body seats 22. 'Sufllclent power may be applied in turning the screws 33 to assure the even and tight sealing engagement of the sealing ridges 28 with the body seats 22. This engage-e ment of the ridges 28 with the seats 22 provides complete annular seals between the rams and the body 10 above and below the rams to positively prevent the leakage of fluid around the rams.

When the well has beeh killed or the pressure condition relieved, the screws 33 are rotated in a reverse direction to retract the rams II. At the start of this reverse rotation of the screws 33 the wedging engagementof the ridges 28 with the seats 22 resists movement of the nuts 5I along the screws 33 and the nuts turn so that the teeth 54- cooperate with the teeth. 53 to move the rams laterally toward their initial eccentric positions, thus freeing the sealing ridges 28 from the body seats 22. Continued reverse rotation of the screws 33 causes the nuts 5| to travel along the screws 50 and the nuts move the rams II back to their retracted positions.

When it becomes desirable or necessary to clean out the body I0 the plugs 36 may be removed and steam or water discharged into the body through the openings 35. If it is desired to replace, repack ,or service the rams II, the plate 28 is removed and moved laterally from the body III to disengage the nuts 5I from the adjacent sides of the rarris 'I I. The rams II may then be moved out through the opening IS. The rams I I may be easily and quickly removed and replaced. The improved blowout preventer of the present invention is small and compact and is light in weight and may be easily mounted in any selected posi tion, for'example. it may be mounted in the cellar of the derrick, at the derrick floor, or above the derrick floor, as desired. Having described only a typical preferred form and application ofmy invention, I do not wish to be limited or restricted to the specific details herein set forth, but wish to reserve to myself any variations or modifications that may appear to those skilled in the art or fall within the scope of the following claims.

I claim:

1. A blowout preventer for controlling a well comprising a body having an opening for communicating with the well, spaced converging seats in the body, closure members movable in the body between retracted positions and active positions where they engage one another in the opening between the seats, means for moving the closure members from the retracted positions to the active positions in engagement with one another, and means made operative by said engagement of the'members with one another for moving the closure members laterally when they reach the active positions to wedge the members between the converging seats.

2. A blowout preventer for controlling a well comprising a body having a substantially vertical opening for communicating with the well, vertically spaced sealing seats in the body around the opening, two closure members movable toward one another in the body in a substantially horizontal line between retracted positions and active positions in the opening where they engage one against the other between the seats,

means for moving the closure members to said active positions, convergent sealing faces on the upper and lower sides of the members, and means for moving the members horizontally in a direction lateral with respect to said line after they have reached said active positions to bring said sealing faces against the seats.

3. A blowout preventer for controlling a well comprising a body having a substantially vertical opening for communicating with the well, vertically spaced seats in the body at the opening, closure members in the body movable between re tracted positions and active positions between said seats where they engage one against the other, said seats converging in a generally horizontal direction lateral of the direction of said movement of the members, convergent sealing surfaces on opposite sides of the members, and means made operative by the engagement of the members one with the other for moving the members laterally to bring said surfaces into sealing cooperation with the seats.

4. A blowout preventer for controlling a well comprising a body having a substantially vertical opening for communicating with the well, seats on the upper and lower walls of the body around the opening, closure members in the body movable toward one another from inactive positions to active positions in engagement with one another between the seats, sealing means on the members cooperating when the members are in said active positions, means for moving the members to said active positions, sealing surfaces on the upper and lower sides of the members, said seats and surfaces being correspondingly convergent in a generally horizontal direction transverse of said movement of the closure members, and means conditioned by said engagement of the members with one another for moving the members in a generally horizontal direction transerse of said movement to bring said surfaces into wedging and sealing cooperation with the seats.

5. A blowout preventer for controlling a well comprising a body having a, substantially vertical opening for communicating with the well, seats on the upper and lower walls of the body around the opening, closure members in the body movable along a substantially horizontal line toward one another from inactive positions to active positions in engagement with one another between the seats. sealing means on the members cooperating when the members are in said active positions, means for moving the'members to said active positions, sealing surfaces on the upper and lower sides of the members, said seats and surfaces being correspondingly convergent in a generally horizontal direction transverse of said horizontal line of movement of the closure members, and gear means automatically made operative by said engagement of the members when the members reach their active positions 'to move the members in a generally horizontal direction transverse of said line of movement so that the surfaces seal with the seats.

6. A. blowout preventer for controlling a well comprising a body having a substantially vertical opening for communicating with the well, seats on the upper and lower walls of the body around the opening, closure members in the body movable along a substantially horizontal line toward one another from inactive positions to active positions in engagement with one another between the seats, sealing means on the members coopcrating when the members are in said active positions, screw means for simultaneously moving the members to their active positions, sealing surfaces on the upper and lower sides of the members, said seats and surfaces converging in a generally horizontal direction transverse of said line of movement of the members, and means operated by the screw means and made operative by the engagement of the members upon reaching their active positions for moving the members in a generally horizontal directiontransverse of said line of movement to bring said surfaces into sealing cooperation with the seats.

7. A blowout preventer for controlling a well comprising a body having an opening for communicating with the well, seats on theupper and lower walls of the body around the opening. closure members in the body movable along a generally horizontal line toward one another from inactive positions to active positions in engagement with one another between the seats, sealing gagement of the members with one another for moving the members in a generally horizontal direction transverse of said line of movement from their active positions to wedge said surfaces against the seats to seal with the same.

8. A blowout preventer for controlling a well comprising a body having an opening for communicating with the well, seats on the upper and lower walls of the body around the opening, 010- sure members in the body movable along a generally horizontal axis toward one another from inactive positions to active positions in engagement with one another between the seats, sealing means on the members cooperating when the members are in said active positions, means for moving the members to said active positions including rotatable screws and turnable traveling nuts on the screws engaging the members, sealing surfaces on the upper and lower sides of the members, the seats and sealing surfaces being convergent in a generally horizontal direction transverse of said axis of movement of the members. and means for moving the" members ina generally horizontal direction transverse of said line of movement from their active positions to wedge said surfaces against the seats to seal with the same, the last named means including meshing gear teeth on the closure members and nuts.

9.. A blowoutpreventer for controlling a well comprising a body having an opening for communicating with the well, seats on the upper and lower walls of the body around the opening, closure members in the body movable toward one another from inactive positions to active positions in engagement with one another between the seats, sealing means on the members cooperating when the members are in said active positions, means for moving the members to said active positions including rotatable screws and tnrnable traveling nuts on the screws engaging the members, sealing surfaces on the upper and lower sides of the members, the seats and sealing surlaces being convergent in a direction transverse oi' said movement of the members, and means for moving the members transversely from their active positions to wedge said surfaces against the seats to seal with the same, the last named means comprising transverse toothed raclrs on the members and series of teeth on the nuts cooperating with the racks to move the members transversely.

iii. A blowout preventer for controlling a well comprising a body having an opening for communicating with the well, seats on the upper and lower walls of the body around the opening, closure members in the body movable along a generally horizontal axis toward one another irom. inactive positions to active positions in engagement with one another between the seats, sealing means on the members co operating when the members are in said active positions, means for moving the members to said active positions, sealing surfaces on the upper and lower sides of the members, said seats and surfaces being correspondingly convergent in a generally horizontal direction transverse of said axis of movement of the closure members, means made operative by the cooperation of the members in their active positions for moving the members substantially horizontally in a direction transverse of said axis of movement to bring said sealing surfaces into sealing cooperation with the seats, and means for lubricating the sealing surlaces.

ii. A blowout preventer for controlling a well comprising a body having an opening for communicating with the welLseats on the upper and lower walls of the body around the opening, closure members in the body movable along a generally horizontal axis toward one another irom'inactive positions to active positions in engagement with one another between the seats, sealing means on the members cooperating when the members are in said active positions, means tor moving the members to said active positions, sealing surfaces on the upper and lower sides of the members, said seats and surfaces being correspondingly convergent in a generally horizontal direction transverse of said axis of .movement of the closure members, means made operative by said engagement of the members with one another for moving the members in a generally horizontal direction transverse of said axis of movement when the members are in cooperation in their active positions to bring said sealing surfaces into sealing cooperation with the seats, and

means for supplying lubricant under pressure to the cooperating seats and surfaces.

12. A blow out preventer for controlling a well comprising a body having an opening for communicating with the well, seats on the upper and lower walls of the body around the opening, closure members in the body movable along a generally horizontal axis toward one another from inactive positions to active positions in engagement with one another between the seats, sealing means on the members cooperating when the members are in said active positions, means for moving the members to said active positions, sealing surfaces on the upper and lower sides of the members, said seats and surfaces being correspondingly convergent in a generally horizontal direction transverse of said movement of the closure members, said seats and surfaces being metallic, and means made operative by the engagement of the members with one another for moving the members horizontally in .a direction transverse of said axis of movement when the members reach their active positions to bring said surfaces into wedging and sealing cooperation with the seats.

13. A blowout preventer for controlling a well comprising a body having an opening for communicating with the well, seats on the upper and lower walls of the body around the opening, closure members in the body movable toward one another from inactive positions to active positions in engagement with one another between the seats, sealing means on the members cooperating when the members are in said active positions, means for moving the members to said active positions including rotatable screws at opposite sides of the pair of members, lugs on the sides of the members, traveling nuts on the screws cooperating withthe lugs to move the members upon rotation of the screws, and means for simultaneously rotating the screws, and means for shifting the members laterally when in their active positions to bring said suriaces'into sealing cooperation with the seats including transverse series of gear teeth on the members, and gear teeth on the nuts meshing with the teeth on the members to shift the members transversely when the nuts turn. 7 I

it. A blowout preventer for controlling a well comprising a body having an opening for communicating with the well, seatson the upper and lower walls of the body around the opening, closure members in the body movable along a generally horizontal axis toward one another from inactive positions to active positions in engagement with one another between the seats, sealing means on the members cooperating when the members are in said active positions, means for moving the members to said active positions, sealing surfaces on the upper and lower sides of the members, said seats and surfaces being correspondlngly convergent in a horizontal direc tion transverse of said axis of movement oi the closure members, means idle during the movement of the members toward one another and made operative by the engagement of the members with one another for moving the members horizontally in a direction transverse of said axis when the members are in cooperation in their active positions to bring said sealing surfaces into sealing cooperation with the seats, inflatable packing dn the inner sides of the members, and means for conducting fluid under pressure to the packing to inflate the same.

15. A blowout preventer for controlling'a well comprising a body having an opening for communicating with the well, seats on the upper and lower walls of the body around the opening, closure members in the body movable toward one another from inactive positions to active positions in engagement with one another between the seats, sealing means on the members cooperating when the members are in said active positions, means for moving the members to said active positions, sealing surfaces on the upper and lower sides of the members, saidseats and surfaces being correspondingly convergent in a direction transverse of said movement 01 the closure members, means for moving the members transversely when they are in cooperation in their active positions to bring said sealing surfaces into sealing cooperation with the seats, said sealing surfaces having grooves, expansible inflatable packing arts on the inner sides 01' the members having their interiors in communication with the grooves,

and means for supplying lubricant under pres the rams along said line toward one another tosaid active positions, and means idle during said movement of the rams for moving the rams in a direction substantially normal to said line to seal with the body after they have reached their active positions.

ELMO 0. LOWE.