Adaptive Conduit Connection, Particularly For Bringing Blowing Petroleum Wells Under Control

Abstract

When a petroleum wellhead conduit part equipped with a clamp-receiving wedging flange and tapered sealing ring seat at one end, as shown in the U.S. Pat. of Watts et al., U.S. Pat. No. 2,766,829, issued Oct. 16, 1956, is to be connected with a part having a bolt-receiving flange, an adapter is provided which may be used for closing in a blowing well by allowing blowout control equipment such as a blowout preventer or master valve to be initially secured to the one part of the adapter, swung into place in an "open" condition and fully circumferentially secured to the adapter. The control equipment may then be closed to shut in the well. Additionally to this special use, the adapter may be used to interconnect parts whose end connectors differ in type from one another.

Description

BACKGROUND OF THE INVENTION

Gray Tool Company of Houston, Texas, and its licensees furnish process plant and petroleum wellhead equipment in which several of the conduit parts such as casing heads, tubing heads, bonnets, valve bodies and spools (parts of wellheads) are provided with ends especially adapted to be sealingly mated with parts having like ends, internally utilizing flexible lipped sealing rings and externally utilizing circumferential clamps as shown in the U.S. patent of Watts et al., U.S. Pat. No. 2,766,829, issued Oct. 16, 1956, for which connections and constituent parts the trademark Grayloc is used. Further examples of the use of Grayloc connections in wellheads are shown on pages 2,108, 2,114, 2,124, 2,126, 2,127 and 2,142 of the Composite Catalog of Oilfield Equipment and Services, 1968-69 Edition, Gulf Publishing Company, Houston, Texas.

Another more generally used connector used for coupling wellhead parts utilizes circumferential flanges on the parts, each being provided with a circle of bolt holes through which bolts are received and have nuts tightened thereon to establish joints. Various sealing elements may be provided between such ends, for instance, A.P.I. gasket rings or lens rings. Examples of the use of bolted flange end connections of wellhead conduit parts are shown in the same edition of the Composite Catalog of Oilfield Equipment and Services on pages 2,103, 2,109, 2,131 and 2,132. As should be apparent, some operators prefer to use the Grayloc connection exclusively, others prefer to use the bolted flange end connection. Many use both or what is available from supplier's inventory. There are occasions when interconnection of parts of both types on hand would save an operator from waiting on shipping of a part of one type or the other, or from waiting for a Grayloc end to be machined on the existing part having the bolted flange end.

One particular instance where there is a need to quickly convert a Grayloc hub for a bolted flange connection occurs when a petroleum well being drilled or completed (with wellhead parts shown on the first aforementioned group of Composite Catalog pages) blows out. When a well is blowing wild, for example through 7-inch casing and there is a flange to which a master valve or blowout preventer can be attached, it has been a normal practice to insert a long bolt through one of the bolt holes in the flange. Then a flanged master valve having a bore at least as large as the bore of the pipe through which the well is blowing and having a bolt circle the same as the flange to which it is to be attached, is also connected to the long bolt, but away from the well flow. The long bolt now serves as a swivel bolt. The master valve is then rotated on the swivel bolt over the well flow, and when it becomes aligned with its mating flange, is lowered to rest on the flange. Some flange bolts are installed and thoroughly tightened. The master valve is now ready to be closed, thereby shutting in the wild well.

In the past, although the excellent history of safe use of connections, as shown in the aforementioned Watts et al. patent, in wellheads has encouraged their utilization, there have been some who have held back on use because of the anticipated difficulty of shutting in a wild blowing well by the above outlined well-known procedure, when parts with Grayloc ends were involved, should it be necessary.

SUMMARY OF THE INVENTION

The present invention provides a connector adapter for quickly adapting conduit ends of the type shown in the U.S. patent of Watts et al., U.S. Pat. No. 2,766,829, to bolted flange connection, especially for instances when fluid is flowing at a rapid rate through the conduit, as occurs when a petroleum well is blowing wild.

When a petroleum wellhead conduit part equipped with a clamp-receiving wedging flange and tapered sealing ring seat at one end, as shown in the Watts et al. patent, is to be connected with a part having a bolt-receiving flange, an adapter is provided which may be used for closing in a blowing well by allowing blowout control equipment such as a blowout preventer or master valve to be initially secured to the one part of the adapter, swung into place in an "open" condition and fully circumferentially secured to the adapter. The control equipment may then be closed to shut in the well. Additionally to this special use, the adapter may be used to interconnect parts whose end connectors differ in type from one another.

The principles of the invention will be further hereinafter discussed with reference to the drawings wherein a preferred embodiment is shown. The specifics illustrated in the drawings are intended to exemplify, rather than limit, aspects of the invention as defined in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of the new clamp;

FIG. 2 is a side elevation view of the new clamp partly broken away and sectioned to expose interior detail;

FIG. 3 is a side elevation view of the new clamp installed on a conduit end of the kind shown in the aforementioned Watts et al. patent and further showing a piece of control equipment pivotally mounted thereon and about to be swung into position over the conduit through bore;

FIG. 4 shows a side elevation view of the same equipment as in FIG. 3 at a later stage wherein the control equipment has been pivoted over the conduit through bore, secured in place and closed to shut in the well.

DESCRIPTION OF THE PREFERRED EMBODIMENT IN CONJUNCTION WITH THE DRAWINGS

In FIGS. 1 and 2 there is shown a conduit connector clamp 10 comprising two arcuate segments 12 which are hinged to one another at 14 adjacent one end of each segment and removably securable to each other at 16 adjacent the opposite end of each segment. Each segment extends through slightly less than 180.degree.. When the clamp is assembled and secured as shown, it provides essentially circumferential annular clamping about the two parts to be secured to one another.

Internally, the annular clamp 10, beginning from its lower, axially downwardly facing end surface 17, is provided with a downwardly and inwardly facing, generally frustoconically curved surface 18 which acts as a centering guide to ease slipping the clamp over a conduit part end. At the upper, inner extent of the surface 18, the clamp segments are provided with a short cylindrically curved surface 20 sized to lie radially adjacent the reduced diameter neck of a conduit part having an end as illustrated in the aforementioned U.S. patent of Watts et al., U.S. Pat. No. 2,766,829.

At the upper extent of the surface 20, the clamp segments are provided with a generally frustoconically curved surface 22 which faces upwardly and radially inwardly and thus increases in diameter as it proceeds upwardly. The surface 22 complements the exterior, clamp-receiving wedging surface of the conduit ends illustrated in the aforementioned Watts et al. patent. At the upper, outer extent of the surface 22, the clamp segments are provided with a radially inwardly facing, axially upwardly extending cylindrical surface 24 sized and positioned to lie adjacent the radially outwardly facing surface on an end of a conduit of the kind shown in the aforementioned Watts et al. patent. At the upper extend of the surface 24, the clamp segments are provided with an annular, axially downwardly facing, radially inwardly extending surface 26 adapted to seat on the upper end surface of a conduit end of the kind shown in the aforementioned Watts et al. patent. At the radially inner extent of the surface 26, the clamp segments 12 are shown provided with a brief cylindrical surface 28 to provide axial spacing for a sealing ring centralizing guide surface 30 which flares upwardly therefrom. The surface 28 is preferably of such diameter as to lie radially closely adjacent the radially outer extent of the exterior rib of a flexible lip sealing ring of the type shown in the aforementioned Watts et al. patent.

The upper extent of the surface 30 merges with the axially upwardly facing annular upper end surface 32 of the clamp.

Referring to FIG. 1, the clamp 10 is provided with a plurality of bolt-receiving openings extending axially thereof between the clamp upper and lower end surfaces on a standard size bolt circle, 12 of such openings being shown with normal angular spacing from one another.

The hinging 14 is provided by ears 34 shown welded at 35 onto each segment. The three ears 34 shown are axially displaced from one another so that they overlap one another with the two ears on one segment receiving the single ear on the other segment between them. The ears could be integrally cast with the respective segments. Each ear 34 has an opening 36 formed axially therethrough. The three openings 36 are in axial alignment and receive an axle in the form of a swivel bolt 38. In the embodiment shown, the bolt 38 is inserted from below, with a washer 40 preassembled thereon so that the head of the bolt 38 lies at 42. At the level where the bolt emerges from the topmost ear opening 36, the bolt shank is shown circumferentially grooved at 44 to receive a snapring 46 which holds the swivel bolt in position as shown with a substantial length of bolt shank protruding above the ears 34. The upper end region of the shank 48 is threaded for a sufficient distance to threadably receive a nut 50.

At the opposite ends of the segments, a quick connect, quick disconnect type securement 16 is provided. By preference, but not of necessity, the securement is of the type shown and extensively discussed in the U.S. patent of Watts, U.S. Pat. No. 3,181,901, issued May 4, 1955. Suffice it to say here that with the securement unlatched and the clamp segments pivoted apart about the bolt 38, the clamp 10 may be slipped about the hub H of a conduit end of the described type in the aforementioned Watts et al. patent, the segments pivoted closed, and the securement 16 latched to secure the clamp 10 on the conduit C (as depicted in FIG. 3). It should be noted that this leaves the sealing ring seat S of the conduit free to receive a sealing ring R, as will be described below, and presents the bolt circle of the flange 54 of the clamp in condition to receive a set of bolts for mating the flange 54 to another part.

The special instance of controlling a wild well in which fluids under pressure from subterranean forces are blowing from a partly completed or damaged or completed well of which the conduit C constitutes a wellhead portion, is depicted in FIGS. 3 and 4. In FIG. 3, the clamp 10 has been secured about the hub through which the fluids are issuing. Out of the path of the fluids, an adapter spool 56 has been pivotally mounted on the swivel bolt 38.

The adapter spool 56 has an item of control equipment 58, particularly a master drilling valve or blowout preventer or the like, secured thereon. Examples of both typical master drilling valves and blowout preventers are illustrated in the aforementioned U.S. patent of Watts et al. Further examples of such items of control equipment abound in the Composite Catalog of Oilfield Equipment and Services, 1968-69 Edition, Gulf Publishing Company, Houston, Texas.

Basically, the purpose of the adapter spool 56 is to provide (a) a means for allowing an item of control equipment to be mounted on the clamp 10 out of the direct path of escaping fluid for pivotal movement into the path of the escaping fluid and (b) for sealed securement of the bolt flange of the clamp 10 with respect to the control equipment.

Accordingly, the adapter 56 is exemplary in form. Provided the item of control equipment 58 itself had a bolt flange of appropriate size on its lower end, and an ear welded thereto for pivotal mounting on the swivel bolt 38, the portion illustrated at 58' could actually be the lower part of the item of control equipment itself, a separate spool then being unnecessary.

However, in the equipment illustrated, it is assumed that the user would not wish to so modify an item of control equipment, and thus a separate adapter is shown provided.

In essence, the adapter 56 is an axially short tubular element 60 having a bolt flange 62 at its lower end, having bolt openings therethrough adapted to axially align with those of the clamp 10, and having at its upper end a flange and securement means 64 complementary to that 66 of the item of control equipment 58. In the instance depicted, the control equipment lower end flange and adapter 56 upper end flange are both of the bolt-receiving type and adapted to receive an unseen A.P.I. sealing ring between them. Alternately, they could be of the clamp-receiving type shown in the aforementioned U.S. patent of Watts et al., U.S. Pat. No. 2,766,829, or of the clamp-receiving type shown in the aforementioned Composite Catalog, on page 1,056, under the heading "AX" Gasket Hubs.

The ear 68 shown welded at 70 to the lower end flange of the adapter 56 projects laterally outwardly therefrom sufficiently to allow the adapter and item of control equipment, preassembled to one another as a control equipment assembly 71 to be mounted on the swivel bolt while out of the direct path of fluid issuing from the conduit C. In installing the control equipment assembly 71, the ear 68, via an opening 72 therethrough, is received on the swivel bolt shank from the upper end of the shank, after which the nut 50 is threaded onto the shank to pivotally mount the adapter.

It should now be noted that the adapter 56 bore 74 at its lower end 76 is provided with an internal, frustoconically curved sealing ring seat 78 which may be a mirror image of the seat S of the conduit hub H. In the instance depicted, the seat 78 tapers at the same cone angle as the seat S, but is of somewhat greater diameter at its lower end. Accordingly the sealing ring R (FIG. 4) sealing between the surfaces 78 and S, although it is of the type shown in the U.S. patent of Watts et al., U.S. Pat. No. 2,766,829, is of a transitional modification as described on page 32 of Gray Tool Company "GRAYLOC" Pipe Fittings Catalog 69. By preference, the sealing ring R is preassembled to the adapter 56 by bolting it to the adapter at 80. (Such preassembly is suggested in FIG. 1 of the U.S. patent of Quebe et al., U.S. Pat. No. 3,400,950, issued Sept. 10, 1968, at 36, and in FIG. 10 of the U.S. patent to Pitts et al., U.S. Pat. No. 3,405,763, issued Oct. 15, 1968, at 350, 352.)

The adapter 56 lower end flange, which extends circumferentially of the adapter, is shown provided with arcuate skirts 82 welded thereto at 84, which project below the lower extent of the sealing ring R so that as the control equipment assembly 71 is moved from its FIG. 3 orientation to its FIG. 4 orientation, the sealing ring lower lip will not be damaged by striking the clamp. When the assembly 71 is over the clamp 10 during movement from the FIG. 3 to the FIG. 4 orientation, the skirts (each of the two of which extend throughout a quadrant or somewhat more) prevent the assembly from dropping down from the level shown in FIG. 3 to the level shown in FIG. 4 until the bore of the assembly 71 is axially aligned with the bore of the conduit C. In this connection, note that the swivel bolt shank is long enough to permit the elevation of the assembly 71 to the position shown in FIG. 3, i.e. so the skirts 82 can clear and be supported upon the clamp 10 upper end. Also note that the radially inner surfaces of the skirts 82 are of just slightly greater diameter than the closed clamp 10 to provide the above-noted support until alignment.

When the control equipment assembly is at the stage depicted in FIG. 3, it is purposefully "open," i.e. if the control equipment consists of a blowout preventer with blind rams, the rams are separated so that the bore of the preventer is free to pass fluids therethrough.

Accordingly, the assembly 71 may be pivoted from its FIG. 3 position to its FIG. 4 position while the well fluids issue from the conduit C, then through the assembly 71 throughbore and to some extent between the clamp 10 and flange 62 of the control equipment assembly, until bolts 90 are installed through the bolt holes of the flange 62 and clamp 10 and tightened as depicted in FIG. 4. Then the control equipment may be closed, i.e. the blowout preventer blind rams forced together, to shut off flow from the well and thus bring it under control. The well may then be further completed, abandoned or repaired in accordance with known procedures.

To summarize the description above, when a petroleum wellhead conduit part equipped with a clamp-receiving wedging flange and tapered sealing ring seat at one end, as shown in the U.S. patent of Watts et al., U.S. Pat. No. 2,766,829, is to be connected with a part having a bolt-receiving flange, an adapter is provided which may be used for closing in a blowing well by allowing blowout control equipment such as a blowout preventer or master valve to be initially secured to the one part of the adapter, swung into place in an "open" condition and fully circumferentially secured to the adapter. The control equipment may then be closed to shut in the well. Additionally to this special use, the adapter may be used to interconnect parts whose end connectors differ in type from one another. To accomplish this when the wellhead part which can most conveniently be tied in to control the well is equipped with a "Grayloc" hub, i.e. a hub of the type illustrated in Watts et al., U.S. Pat. No. 2,766,829, the present invention provides an adapter clamp which is shown by itself in FIGS. 1 and 2. The adapter clamp is designed to wrap around and fully engage a "Grayloc" hub to convert the hub to a flange connection. The adapter clamp is provided with a swivel bolt which also acts as a hinge bolt sufficiently laterally displaced from well flow that an adapter and master valve or blowout preventer may be mounted thereon away from the well flow. The control equipment assembly has a lower flange with the same bolt circle as the adapter clamp. A seal ring is attached to the adapter clamp flange and skirts partly surrounding that flange protect the seal ring. These skirts extend through quadrants and are installed 180.degree. apart so that when the control equipment (in open condition) is swung over the well flow, the skirts drop down to between the hinge bolt and securement of the clamp. During the rotation operation, the skirts ride on top of the clamp, thus preventing the seal ring from being damaged. When the adapter is in proper position over the well flow, the inside arc of the skirts fit the outside arc of the clamp. The flange bolts may then be installed between the clamp and the adapter lower end flange and the control equipment closed to control the well and cut off flow therefrom.

The device of the invention, no doubt, has other additional uses than the use principally described above, and such should become apparent to those skilled in the art after reading the above description in association with the accompanying drawings. For instance, the device may be used under similar circumstances, to control flow from a petroleum, water or chemical pipeline having a damaged shutoff valve.

Familiar terms of spatial orientation such as "up" and "down" or similar ones used in this specification describe preferred, usual orientation of the devices under discussion. They are used to convey the relevant concepts most expeditiously and are not intended to exclude inversion, canting, recumbency or other varied spatial orientation of the devices described, unless the need for a particular orientation is evident.

It should now be apparent that the adaptive conduit connection as described herein above possesses each of the attributes set forth in the specification under the heading "Summary of the Invention" hereinbefore. Because the adaptive conduit connection of the invention can be modified to some extent without departing from the principles of the invention as they have been outlined and explained in this specification, the present invention should be understood as encompassing all such modifications as are within the spirit and scope of the following claims.

Claims

What is claimed is:

1. A clamp-type conduit connector comprising a clamp including means defining a plurality of arcuate clamp segments, each having two angularly opposite ends; means defining a radially inwardly opening arcuate recess on each segment, extending angularly on the inner side of each segment, each said recess being configured to receive a corresponding angular portion of a wedge-type conduit end flange; securement means on each of two adjacent ones of said ends of different ones of said segments cooperable for removably securing said clamp circumferentially about a conduit part end in clamped relation thereto; at least one ear mounted on each of two adjacent other ones of said ends of different ones of said segments, said ears lying in adjacency parallel to the longitudinal axis of said clamp; hinge pin means hinging said ears to one another about an axis parallel to the longitudinal axis of said clamp, said hinge pin means including an elongated shank extending axially beyond said ears in one direction; a control equipment assembly including a tubular body having a through bore and means for selectively permitting and obstructing fluid flow through said throughbore; means defining a circumferentially extending securement flange on said control equipment assembly adjacent the lower extent thereof; at least one ear mounted on said control equipment and extending laterally outwardly of said securement flange; said hinge pin means mounting the last-mentioned ear for providing pivoting of said control equipment assembly about the longitudinal axis of said hinge pin means between one extreme wherein said control equipment assembly is fully out of axial registry with the clamp and another extreme wherein said control equipment is fully in axial registry with the clamp; means defining a circumferential sealing surface on said control equipment assembly securement flange configured to accept a seal for sealing between the securement flange and the conduit part end; and cooperative securement means on said securement flange and said clamp for drawing said securement flange and said clamp securely together to connect the same axial alignment with one another to sealingly connect said control equipment assembly and the conduit part end bearing said clamp.

2. The clamp-type conduit connector of claim 1 wherein said control equipment assembly securement flange comprises a bolt flange having means defining a plurality of bolt openings axially therethrough, angularly spaced from one another about a bolt circle; and wherein said cooperative securement means comprises means defining a corresponding plurality of correspondingly located bolt openings axially through the segments of said clamp, and a plurality of bolt and nut assemblies, each secured through respective of said bolt flange and clamp bolt openings.

3. The clamp-type conduit connector of claim 1 wherein said control equipment assembly comprises a blowout preventer.

4. The clamp-type conduit connector of claim 1 wherein said control equipment assembly comprises a master drilling valve.

5. The clamp-type conduit connector of claim 2 wherein said circumferential sealing surface comprises a frustoconically curved internal sealing ring seat in said control equipment assembly through bore which enlarges in diameter toward an end of the through bore nearest said clamp; a sealing ring having two external, oppositely frustoconically curved, coaxial, circumferential sealing surfaces defined thereon at regions thereof which are axially displaced from one another; and securement means fastening said sealing ring to said control equipment assembly bolt flange with one sealing surface of said sealing ring positioned for sealing engagement with said sealing ring seat of said control equipment assembly through bore.

6. The clamp-type conduit connector of claim 5 further including seal ring protecting arcuate skirt means mounted on said control equipment assembly bolt flange and protruding therebelow to at least the lower extent of said sealing ring; said arcuate skirt means being positioned to partially circumferentially surround said clamp and to lie angularly between the clamp segment ears and the means for removably securing the clamp about a conduit part end, when said control equipment assembly is brought into axial alignment with said clamp.

7. Apparatus for effecting control of a petroleum well blowing wild through a wellhead conduit part having an external, clamp-receiving wedging flange extending circumferentially thereon and an internal, frustoconically curved sealing ring seat in the bore thereof, both at the upper end of said wellhead conduit part, said apparatus comprising: a segmental, contractile-expansible clamp having recess means defined thereon configured to receive and extensively engage said wellhead conduit part external, clamp-receiving wedging flange; a control equipment assembly including a body portion having a throughbore and means for selectively permitting and preventing fluid flow through said throughbore; hinge means pivotally securing said control equipment assembly to said clamp for pivoting said control equipment assembly from a first position fully laterally off set from the through bore of the wellhead conduit part to a second position in axial alignment with the throughbore of the wellhead conduit part; a bolt flange being circumferentially provided on said control equipment assembly adjacent the lower extent thereof, a plurality of corresponding bolt-receiving openings being defined through said bolt flange and in said clamp, and a corresponding plurality of bolt assemblies for securely bolting said bolt flange to said clamp, whereby once said clamp has been installed and contracted on the wellhead conduit part wedging flange with the control equipment assembly in the first position thereof and in condition to permit the flow of fluid therethrough, the control equipment assembly may be pivoted to said second position thereof, said bolt assemblies securely installed and said control equipment assembly selective means actuated to prevent flow of fluid therethrough to thus control blowing of fluids from the petroleum well.

8. The apparatus of claim 7 further including means defining an internal, frustoconically curved sealing ring seat in the throughbore of said control equipment assembly adjacent the lower extent thereof; and an annular sealing ring having two axially oppositely directed lips; means defining two oppositely tapering external frustoconically curved sealing surfaces on said sealing ring, one on each lip; said sealing ring sealingly engaging the sealing ring seat of said control equipment assembly throughbore and being configured to seal with the sealing ring seat in the bore of the wellhead conduit part upper end upon securement of said bolt assemblies between said bolt flange and said clamp.