US3139932A

US3139932A - Wellhead with tool diverter

Info

Publication number: US3139932A
Application number: US155434A
Authority: US
Inventors: Glenn D Johnson
Original assignee: Shell Oil Co
Current assignee: Shell USA Inc
Priority date: 1961-11-28
Filing date: 1961-11-28
Publication date: 1964-07-07
Anticipated expiration: 1981-07-07

Description

July 7, 1964 G. D. JOHNSON 3,139,932

WELLHEAD WITH TOOL DIVERTER Filed Nov. 28. 1961 BY: zqfm" HIS AGENT FIG. 5

United States Patent 3,139,932 WELLHEAD WITH TOOL DIVERTER Glenn D. Johnson, Downey, Calif., assignor to Shell Oil Company, New York, N.Y., a corporation of Delaware Filed Nov. 28, 1961, Ser. No. 155,434 Claims. (Cl. 166-95) This invention relates to equipment used at the top of an oil or gas well and pertains more particularly to a wellhead assembly adapted to be secured to the top of a well casinghead for controlling the flow of fluid from the well while providing apparatus by which the wellhead assembly can be entered vertically for work-over operations, while at the same time a side entry into the wellhead assembly is provided so that various tools, instruments and other devices can be circulated into the well. This invention is especially concerned with a device of simple design and positive action which is positioned in a wellhead assembly for selectively diverting a circulating object into one of two conduits in the wellhead assembly.

A recent development in the drilling and completion of oil and gas wells has been the drilling and completion of underwater wells wherein the wellhead assembly and the casinghead may be both positioned hundreds of feet below the surface of the Water at an oifshore location. In order to carry out maintenance and other operations on the well wherein the Wellhead assembly is positioned a considerable distance below the surface of the water, methods for carrying out these operations have been developed. One of these methods has been classified as a through-the-flow-line well maintenance technique. For performing the required operations involved in maintaining a well in this manner, certain tools and other devices which are capable of being pumped into and out of the well bore through the production flow line have been developed. Since these maintenance tools must be pumped into the well bore, and since they are not able to pass around the right angle bend in a normal wellhead assembly, new types of wellhead fittings are required to carry out the proposed operations.

One form of a wellhead assembly particularly adapted for this purpose is adapted to be secured to the top of a well casinghead for controlling the fluid flow from a well while providing, in communication with the production string, dual entry ports orconduits which selectively permit the vertical entry of devices into the well. The wellhead assembly includes a casinghead closure connected to the casing which includes a spool member having at least one vertical conduit therethrough in register with a tubing string within the well, and a smoothlycurved side conduit branching upwardly and outwardly from the side wall of the spool member and from the vertical conduit therein. A closure device is provided for closing the vertical conduit through the spool member when it is not in use. The smoothly-curved side conduit is normally connected to a production flow line leading from the well and runningalong the'ocean floor.

It is a primary object of the present invention to provide a wellhead assembly with an apparatus for selectively diverting a circulating object being pumped through the tubing string of the well into one of two discharge cconduits of the wellhead assembly.

Another object of the present invention is to provide an underwater wellhead assembly with apparatus for diverting an object leaving the wellhead assembly through the same conduit that it entered the wellhead assembly.

A further object of thepresent invention is to provide a wellhead assembly, having a Y-branched tubing string therein, with a tool diverter apparatus at the junction of the Y which is automatically positioned to close one 3,139,932 Patented July 7., 1964 branch of the Y by a tool entering the well through the other branch of the Y, with the tool diverter remaining in its set position so as to divert the object or tool leaving the well out the same conduit that it entered the well.

Still another object of the present invention is to provide a tool diverter apparatus for a wellhead assembly having a smoothly curving side conduit as well as a ver tical conduit, the tool diverter apparatus being adapted substantially to close the vertical conduit while having a portion thereof shaped so as to form a continuation of the inner wall of the smoothly curved side conduit.

These and other objects of the present invention will be understood from the following description taken with regard to the drawing, wherein:

FIGURE 1 is a longitudinal view taken in partial cross section of a wellhead spool member together with the tool diverter assembly in accordance with the present invention;

FIGURE 2 is a longitudinal view taken in partial cross section along the line 22 of FIGURE 1;

FIGURES 3 and 4 are enlarged detail views of facing portions of one form of a positioning device for the tool diverter assembly of FIGURES 1 and 2;

FIGURE 5 is a fragmental view taken in cross-section of the spool piece of FIGURE 1 wherein the tool diverter is provided with another form of positioning device; and

FIGURE 6 is a schematic view illustrating an arrangement of an underwater wellhead assembly positioned on the ocean floor in accordance with the present invention.

While the wellhead assembly of the present invention is described hereinbelow with regard to a well having a single production tubing string suspended therein, it will be readily apparent that the present wellhead assembly can be modified so as to be employed on wells having two concentric strings of tubing or on wells having two or more parallel strings of tubing suspended within the well.

Referring to FIGURE 6 of the drawing, a Wellhead assembly 11 is shown as comprising one or more strings of concentric pipe or well casing 12 in which one or more production strings 13 are suspended. The wellhead assembly 11 comprises any suitable casinghead together with the necessary valves and other fixtures to form a production head or a Christmas tree. The production head would include a master valve 14 for closing ofl flow through the production tubing 13, and a side discharge conduit 15, having a valve 16 therein, may be provided for controlling flow of fluid from the well casing 12 outside the tubing string 13. Positioned above the master valve 14 is a Y-branched spool piece 17 having a vertical discharge port 18 through the top thereof and a smoothly curved side conduit or port 19. The vertical run of the spool piece 17 may be closed by a valve 21 and a removable cap or plug 22 while the side outlet 19 is preferably provided with a flow control valve 23 prior to being connected to a flow line 24 from the well which would bend downwardly to the ocean floor 25 and run along the ocean floor to shore or to an offshore production handling installation. In the present installation, the

valves

14, 21 and 23 are necessarily of the fully opened type so that tools, instruments or other devices can be circulated through the flow line 24 and the side conduit 19 into the well, or alternatively, after cap 22 has been removed and valve 21 opened, could be inserted through the vertical run of the spool piece 17 and thence downwardly into the production tubing string 13 in the well.

In FIGURE 1 the spool piece 17 is shown as being provided with a tool diverter assembly of the present invention which comprises a depending elongated arm member 27 which is pivotally mounted at its upper end by a pivot pin 28 located at the junction 29 between the vertical conduit 18 and the side conduit 19. The arm member 27 is fixedly secured to the pin 28 in any suitable manner, as by a key 29a. The end 28a of the pin 28 is preferably provided with a wrench head so the arm may be positioned from outside the spool piece, if desired. The lower end of the arm member 27 is tapered as at 31 so that its lower edge fits relatively tightly against the inner wall of the spool piece so as not to cause a tool or other device to hang up on the lower edge of the arm as it is being circulated or withdrawn upwardly through the spool piece 17. Additionally, one wall of the arm member 27 is slightly curved, as at 32, so as to form a continuation of the natural curve of the side conduit 19. If desired, the same face 32 of the arm member 27 may also have a concave shape to match the wall of the conduit.

As shown in FIGURE 1, the arm element 32 is in a vertical position indicating that the last tool to be passed through the spool piece 17, either by circulating it therethrough or by lowering it on the end of a pipe string or a wire line, was passed through the vertical run 18 of the spool piece. The arm member maintained the position illustrated as the tool was withdrawn from the spool piece and will remain in that position until a tool enters the side conduit 19 and contacts the arm 27 to force it over to its alternate position illustrated at 27a.

If the arm element were positioned for free movement about the pivot pin 28, the arm 27 would move back to its vertical position after a tool had passed downwardly through the side conduit 19 and into the production tubing of the well. Upon being circulated up the well again, the arm 27 being in its vertical position would prevent a tool from being discharged out the side conduit, the conduit it had entered. It is therefore necessary to provide suitable positioning means whereby the arm element 27 will maintain the same position to which it is forced when a tool or object passes into the well, at least until the time that it has passed out of the well again.

One form of a positioning device is shown in FIGURE 2. The pivot pin extends between one wall 17b of the housing and a closure cap 33 secured to the spool piece, as by bolts 34, and being provided with a seal 35 for closing a horizontal drilled hole 36 in a fluidtight manner. Slidably mounted for axial movement along the pivot pin 28, within the hole 36, is a bushing 37 having a key 38 mounted in a keyway 39 to prevent the bushing 37 from rotating. A compression spring 40, mounted between the bushing 37 and the closure cap 33, constantly urges bushing 37 tightly against the adjacent face of the hub 41 at the end of the arm element 27.

The face of the bushing 37, in contact with the hub 41 of the arm member 27, is shown in FIGURE 3 as being provided with a V-shaped bar element or indexing wedge extending outwardly from the face of the bushing. The adjacent face of the hub 41, as shown in FIGURE 4, is provided with a pair of indexing

notches

45 and 46 similar in shape to the indexing wedge 43 carried on the adjacent face of the bushing 37, and at least as long as the wedge 43. The indexing

notches

45 and 46 are at designed angles to each other so that the indexing wedge 43 is in one notch, say 46, when the arm element 27 (FIGURE 1) is in its vertical position, with the wedge element 43 being movable to the indexing notch 45 when the arm element 27 is moved to position illustrated by 27a (FIGURE 1).

When a tool or other device is pumped through the flowline 24 (FIGURE 6) and into the side conduit 19 of the spool piece 17 with the arm element 27 in its vertical position, the tool would force the arm member 27 to position 2711. During this operation, movement of the wedge 43 oue of the indexing notch 46 would cause the bushing 37 to be forced away from the hub 41 of the arm member 27 until the arm element had assumed position 27a (FIG- URE l) at which time the compression spring 40 (FIG- URE 2) would force the indexing wedge 43 in the face of the bushing 37 into the other indexing notch 45 on the face of the hub with sufficient pressure to maintain the arm element in position 27a (FIGURE 1). Thus the arm element would maintain this position so that when the tool was circulated up the well and through the spool piece 17, it would be discharged out the side conduit 19 rather than getting trapped in the vertical run 18 of the spool piece 17.

While the arm element 27 in FIGURE 2 is shown as being substantially as wide as the bore of the conduit in which it is positioned, it is to be understood that it could be considerably narrower and still effectively divert tools into the proper conduit since most tools being circulated through the flow line and production tubing string are normally just a little smaller than the flow line or tubing string 13. At the same time a narrow arm member would permit circulation of well fluid by the arm whether the arm member was in its vertical or deflected position, thus obviating the need of sending a tool or other device into the well to deflect the arm member to its side conduit position prior to producing fluid from the well.

It is also to be understood that various types of positioning means may be employed for maintaining the arm member 27 in one of the two selected positions. Thus, as illustrated in FIGURE 5 of the drawing, the arm member 27 may be provided with one or a pair of

magnets

48 and 49 positioned in the lower tapered end thereof for contact with the side walls of the spool piece 17 with magnet 49 holding the arm 27 in the vertical position and magnet 48 holding the arm member 27 in its deflected or side conduit position.

While the arm positioning means described with regard to FIGURES 2, 3 and 4 illustrate a spring-loaded bushing 37 having an indexing wedge 43 designed for mating with either of cooperating indexing

notches

45 and 46 in the hub 41 of the arm element 27, it is to be understood that any suitable type of detent means may be employed as an arm-positioning device, such for example as springloaded balls or dogs. It is also understood that the toolswitching or deflecting arm member 27 of the present invention could be mounted in a spool piece having a second conduit smoothly curving to the side opposite the other smoothly curving side conduit 19 rather than having a vertical through bore 18.

I claim as my invention:

1. A wellhead assembly comprising a vertically-positioned pipe string, a Y-branched spool piece connected into said pipe string, said spool piece having a vertical through bore in coaxial alignment with said pipe string, a smoothly-curving branching side bore adapted to be connected to a pipe line, tool switching means pivotally mounted within and to said spool piece adjacent the intersection of said through bore and said side bore, said tool switching means including a depending arm element pivotally mounted at the top thereof to the wall of said spool piece at the intersection of said bore thereof, and impact-actuatable positioning means carried by said arm element, said positioning means including means engageable with said spool piece for positioning and retaining said arm element against the inner wall of said spool piece to block selectively one of said bores against the passage of a tool thereinto from said pipe string and to open the other of said bores, said positioning means adapted to be actuated by a tool striking said arm element as it passes through one of said bores into said pipe string.

2. The apparatus of claim 1 wherein said positioning means comprises a first portion carried on one side of said arm element on the pivotally-mounted end thereof said first portion being movable with said arm element, a second portion carried on the inner wall of said spool piece adjacent said first portion, spring means mounted in contact with said second portion for urging it against said first portion, said second portion being fixedly mounted against movement in the plane of said movable arm element, detent means carried by one of said portions on the surface adjacent said other portion, and detent-receiving means being carried by said other portion of said positioning means.

3. The apparatus of claim 1 wherein said positioning means comprises magnet means carried by the end of said arm element opposite the pivoted end.

4. The apparatus of claim 1 wherein said positioning means comprises detent means carried by said spool piece adjacent the pivoted end of said arm element, a pair of detent-receiving indexing means carried by the portion of the arm element adjacent said detent means of said housing whereby said detent means are selectively receivable in one of said detent-receiving means.

5. The apparatus of claim 4 wherein the detent means comprises a spring-loaded indexing element carried by said spool piece and bearing against the pivoted end of said arm element, and wherein said detent-receiving means comprises a pair of recess means formed in the pivoted 6 end of said arm element adjacent said indexing element, said pair of recess means positioned on different radial lines from the pivot point of said arm element, the angle between said radial lines being equal to the angular movement of said arm element within said spool piece.

References Cited in the file of this patent UNITED STATES PATENTS 393,700 Goebel Nov. 27, 1888 398,836 Lieb Mar. 5, 1889 599,557 Fordyce Feb. 22, 1898 904,414 Earl Nov. 17, 1908 1,733,026 McGuinness et a1 Oct. 22, 1929 2,225,840 Newton Dec. 24, 1940 3,055,429 Tausch et a1. Sept. 25, 1962 FOREIGN PATENTS 471,865 Germany Feb. 19, 1929

Claims

1. A WELLHEAD ASSEMBLY COMPRISING A VERTICALLY-POSITIONED PIPE STRING, A Y-BRANCHED SPOOL PIECE CONNECTED INTO SAID PIPE STRING, SAID SPOOL PIECE HAVING A VERTICAL THROUGH BORE IN COAXIAL ALIGNMENT WITH SAID PIPE STRING, A SMOOTHLY-CURVING BRANCHING SIDE BORE ADPATED TO BE CONNECTED TO A PIPE LINE, TOOL SWITCHING MEANS PIVOTALLY MOUNTED WITHIN AND TO SAID SPOOL PIECE ADJACENT THE INTERSECTION OF SAID THROUGH BORE AND SAID SIDE BORE, SAID TOOL SWITCHING MEANS INCLUDING A DEPENDING ARM ELEMENT PIVOTALLY MOUNTED AT THE TOP THEREOF TO THE WALL OF SAID SPOOL PIECE AT THE INTERSECTION OF SAID BORE THEREOF, AND IMPACT-ACTUATABLE POSITIONING MEANS CARRIED BY SAID ARM ELEMENT, SAID POSITIONING MEANS INCLUDING MEANS ENGAGEABLE WITH SAID SPOOL PIECE FOR POSITIONING AND RETAINING SAID ARM ELEMENT AGAINST THE INNER WALL OF SAID SPOOL PIECE TO BLOCK SELECTIVELY ONE OF SAID BORES AGAINST THE PASSAGE OF A TOOL THEREINTO FROM SAID PIPE STRING AND TO OPEN THE OTHER OF SAID BORES, SAID POSITIONING MEANS ADAPTED TO BE ACTUATED BY A TOOL STRIKING SAID ARM ELEMENT AS IT PASSES THROUGH ONE OF SAID BORES INTO SAID PIPE STRING.