US3050126A - Integral well head assembly - Google Patents

Description

Aug. 21, 1962 J. M. LEBEAUX ETAL 3,050,126

INTEGRAL WELL HEAD ASSEMBLY Filed Aug. 18, 1958 6 Sheets-Sheet 1 TIB 1 INVENTORS JACOB M. LEBEAUX PETER L. DE MARSH ATTO RN EY 1962 J. M. LEBEAUX ETAL 3,050,126

INTEGRAL WELL HEAD ASSEMBLY Filed Aug. 18, 1968 6 Sheets-Sheet 2 IO I2 3s 36 l6 l8 INVENTORS JACOB ILLEBEAUX PETER L.DE MARSH BY M ATTORNEY Aug. 21., 1962 J. M. LEBEAUX ETAL 3,050,126

INTEGRAL WELL. HEAD ASSEMBLY Filed Aug. 18, 1958 6 SheecsSheet 3 0 INVENTORS F 15 5 Moon m. LEBEAUX PETER L. DE MARSH ATTORNEY Aug. 21, 1962 J. M. LEBEAUX ETAL 3,050,126

INTEGRAL WELL HEAD ASSEMBLY Filed Aug. 18, 1958 6 Sheets-Sheet 4 TIE E INVENTORS I7 JACOB u. LEBEAUX PETER 1.. as MARSH ATTORNEY 1962 J. M. LEBEAUX ETAL 3,050,126

INTEGRAL WELL HEAD ASSEMBLY Filed Aug. 18, 1958 6 Sheets-Sheet 5 F'Il3 '7 35 -l8 26 b 20 b C mi D 26 b INVENTORS JACOB M. LEBEAUX PETER L. DE MARSH ATTORNEY 1962 J. M. LEBEAUX ETAL 3,050,126

INTEGRAL WELL HEAD ASSEMBLY Filed Aug. 18, 1958 6 Sheets-Sheet 6 F'IE... IEI

INVENTORS JACOB M. LEBEAUX PETER L. DE MARSH ATTORNEY United States Patent M 3,050,126 INTEGRAL WELL HEAD ASSEMBLY Jacob M. Lebeaux and Peter L. De Marsh, Houston, Tex.,

assignors to FMC Corporation, a corporation of Delaware Filed Aug. 18, 1958, Ser. No. 755,470 Claims. Cl. 166-97) This invention pertains to flow controlling apparatus for producing wells, and more particularly to an integrated well head or Christmas tree structure.

Commonly known well head structures comprise a complicated collection of valves and various other assemblies bolted together by means of flange connections to form the flow control assembly, commonly referred to as a Christmas tree, at the upper end of a well. It is not uncommon for a Christmas tree assembly to reach eighteen or twenty feet in height thus requiring additional substructure to afford .access to the wing valves and to the top of the tree. Further, such an excessively high Christmas tree often requires the dismantling of the entire assembly to permit movement of a barge or portable drilling platform because it will not clear the tree after the well completion.

It is therefore an object of this invention to provide an improved well head assembly.

Another object is to provide an integrated Christmas tree structure which is greatly reduced in heightand overall weight but which is capable of efficiently performing the necessary functions of flow control.

Another object of the invention is to provide a well head structure wherein the variousvalves can be operatively installed simply by being plugged into valve receiving openings provided for that purpose in the well head.

Another object is to provide an improved method of making a well head structure.

Another object is to provide a method of making a well head structure whereby the structure is so strengthened that it can be made to greatly reduced dimensions without reducing its resistance to internal pressure.

A further object of the invention is to provide a method of forming .a well head structure which contemplates shrinking a hardened steel liner into the longitudinal bore therethrough to increase the overall strength of the well head structure.

A still further object of the present invention is to provide a method of forming a well head structure which contemplates subjecting the bore through said structure to hydraulic pressure sufiicient to cause some stretching of the inner wall of said structure, whereby, when said pressure is released the inner wall of said structure will be under compression while the outer wall is under tension, and thereby increase the overall strength of said structure.

These and other objects and advantages of the instant invention will become apparent from the following description, taken with the accompanying drawings, in

which:

FIG. 1 is an elevation of a well head structure incorporating the principles of the invention.

FIG. 2 is a vertical section of the device shown in FIG. 1 with the valves removed.

FIG. 3 is a section taken on line 3-3 of FIG. 1 and particularly illustrates the manner of inserting the several control valves. 1

FIG. 4 is a fragmentary section of a portion of FIG. 3 drawn to an enlarged scale to illustrate the details of the valve installation.

FIG. 5 is similar to FEG. 4 and illustrates an alternate sealing arrangement between the body of the well head assembly and thevbody of the valve assembly.

3,050,126 Patented Aug. 21, 1962 FIG. 6 is a sectional view similar to FIG. 2 and illustrates a modified well head assembly having a strengthening liner installed therein.

FIG. 7 is a section of a well head assembly modified for use with a dual tubing string well installation.

FIG. 8 is a sectional view of a combined tubing hanger and control valve assembly incorporating the same inventive concepts as the devices illustrated in FIGS. 1-7.

Referring now to the drawings, and particularly to FIGS. 1-4 thereof, the well head assembly generally indicated 10 comprises a cruciform body 12 having a central longitudinally extending bore 14 extending therethrough. The body 12 is provided at its lower end with a flange 13 adapted to be connected to a similar flange 15 at the upper end of a tubing head 17 in the manner well known in the art. Two laterally extending branch bores 16 and 18 connect with the central bore 14 and extend laterally on the axes of the two arm portions 20 and 22, respectively, of the cruciform body 12.

Three laterally extending tapered valve receiving bores or openings 24, 26 .and 28 extend through the body 12 and intersect the longitudinal bore 14 therethrough. The tapered openings 24, 26 and 28 are adapted to receive integrated valve assemblies 30, 32 and 34, respectively, in the manner described hereinbelow. Similarly, tapered bores or openings 36 and 38 extend laterally through the arm portions 24 and 22 of the body 12 and intersect the lateral bores 16 and 18, respectively. The tapered openings 36 and 38 are adapted to receive valve assemblies 41 and 42, respectively.

The valve assemblies 30, 32, 34, 40 and 42 are all identical in construction and installation, therefore only the structure and installation of the valve assembly 30 will be described in detail. The valve assembly 30 comprises a valve body or housing 50 having a tapered outer surface 52 complementary to the tapered opening 24 into which it fits. Two ports 54 and 56 extend transversely through the valve body or housing 50 and provide communication between the central bore-14 of the body 12 of the well head assembly 10 both above and below the valve body 50 and a cylindrical cavity 58 (FIG. 4) formed in the valve body 50.

A movable valve member in the form of a cylindrical valve plug 60 (FIG. 3) having a transverse bore 62 therethrough is rotatably received within the cavity 58 and is retained therein by a screw plug 64 threaded into the valve body 50. A stem 66 is fixed to one end of the valve plug 60 and extends through a suitable bore 67, whereby the plug 60 may be rotated to bring the bore 62 into or out of register with the ports 54 and 56 in the valve body 50 by rotating the stem 66. The outer end '68 of the stem 66 is square in cross section to permit the use of a wrench for turning the valve plug 60. An indicator plate 70 is fixed to the square portion 68 of the stem 66. As can best be seen in FiG. 1, the plate 70 has a portion of its periphery cut away as at 71, and a pin 72 fixed to the valve body 50 projects into the cutout 71. The valve assembly 30 can be closed by turning the valve stem 66 clockwise until one end of the cutout 71 engages the pin 72 and can be opened by turning the valve stem counterclockwise until the other end of the cutout portion 71 contacts the pin 72.

The internal valve structure described briefly above forms no part of the instant invention which contemplates the use of valves other than plug valves e.g., gate valves, globe valves, etc. The important feature in this connection is that whatever type of internal valve structure is used, the outer surface of the valve body is shaped to fit within any one of the valve receiving openings provided in the body 12 of the well head assembly 10, and that ports in the valve body establish communication with f 3 the parts of the bore 14 of the body 12 above and below the valve body when the valve is open.

After the valve body has been inserted into the opening 24 in the well head assembly body 12, a retaining ring (FIGS. 3 and 4) is threaded onto suitable threads 82 on the reduced end of the body 50 which extends beyond the smaller end of the opening 24. As can best be seen in FIG. 1 the ring 86 is provided with suitable notches 84 to permit the use of a spanner wrench to tighten the ring 80 and draw the valve body 50 tightly into the tapered opening 24. Proper registration of the ports 54 and 56 with the bore 14 in the Well head assembly 10 is insured by the use of a key 86 which fits into suitable keyways 88 and 90 formed in the valve body 50 and the body 12 of the well head assembly 10, respectively.

The seal structure for sealing between the valve body 50 and the body 12 of the well head assembly 10 comprises a pair of grooves 106' and 102 formed in the outer surface of the valve body 50 encircling the port 54. A pair of O- rings 104 and 106 are received within the grooves and 102, respectively. It will be noted that the outer groove 1% is wider than the O-ring 104 received therewithin, and that the O-ring 1114 is of such size that it lies adjacent the outermost wall of the groove 100. A drilled passageway 108 provides communication between the groove 1% adjacent the inner portion thereof and a second drilled passageway 110 which connects with a suitable tapped opening 112 at the outer face of the valve body 50'. A suitable fitting (not shown) can be threaded into the opening 112 and can be used for injecting suitable plastic sealing material through the passageways 108 and 110 to energize the O-ring 104. The sealing assembly between the valve body 50 and the body 12 of the well head assembly 10 is completed by similar grooves and O-rings encircling the port 56, and a similar arrangement for injecting plastic sealing material into one of the grooves.

In the modified sealing structure shown in FIG. 5, the valve body 50' is adapted to be inserted into a suitable opening 24' in the body 12 of the well head assembly 10'. In this modification the opening 24" is not a smoothly tapered bore as is the opening 24 described above. The opening 24' comprises a large bore connected by a tapered surface 122 with a slightly smaller bore 124. The bore 124 is connected by a tapered surface 126 with a radial abutment surface 128 formed at the inner end of a still further reduced diameter bore 130.

The outer surface of the valve body 50' comprises a cylindrical portion 132 slidably fitted to the small diameter portion 130 of the opening 24. The cylindrical surface 132 is connected to a tapered surface 134 by a radial abutment surface 136 that is slidably fitted to the tapered surface 126. The tapered surface 134 is connected by a cylindrical surface 135, slidably fitted to the bore 124, with a tapered surface 137 complementary to the tapered surface 122 in the opening 24'.

-A groove 140 is formed in the tapered surface 122 in the opening 24' and is adapted to receive a tapered metal sealing ring 142 adapted to abut the tapered surface 137 on the valve body 50'. A second tapered metal sealing ring 144 is received within the tapered portion 126 of the opening 24 and is adapted to seal against the cylindrical surface 132 on the valve body 50'. When the valve bbdy 50 is inserted into the opening 24, and is seated therein by tightening the locking ring 80' thereof, the tapered surfaces 126 and 137 energize the metal sealing rings 144 and 142, respectively.

The modification of FIG. 5 is provided with a groove encircling the port 54' in the valve body 50, and a suitable O-ring 152 is received within the groove 150. A similar groove and O-ring is provided concentric with the port 56. Additional sealing is provided by an annular groove 154 extending around the outer surface of the valve body 50' inwardly from the sealing ring 142. A longitudinally extending groove 156 connects the groove 154 with the space between the abutment surface 136 and the sealing ring 144. A suitable drilled passageway 158 in the body 12' of the well head assembly 10' connects the groove 154 with a second drilled passageway 160 which in turn is connected to an opening 162 in the outer surface of the body 12 of the well head assembly 10'. The opening 162 is tapped to receive a suitable fitting (not shown) whereby plastic sealing material can be pumped through the passageways 160 and 158 into the groove 154 and through the groove 156 into the space between the sealing ring 144 and the abutment surface 136.

In the fabrication of the body 12 or 12 of the well head assembly 10 or 10', respectively, contemplated by the instant invention, the device is first cast or forged to the general configuration illustrated in FIG. 2. The entire unit is then annealed by heating to 2200 F. and subsequent cooling to ambient condition. The strengthening process is then carried out by again heating the entire unit to approximately 1750 F. and quenching the bore through the unit by inserting a perforated tube therein and spraying with water for approximately two and onehalf minutes. The entire unit is then immersed for a period of approximately seven minutes. After the unit is removed from the immersion bath, the casting or forging will be at a temperature of approximately 180 F. The surface hardness will be in the order of 64 Rockwell C and the thermal midwall will be located approximately at the geometric midwall of the unit. The residual stress wall interfaces will be located approximately one-third of the thickness of the wall from the outer and inner faces of the unit, respectively. The entire unit is then tempered to the required hardness by heating it to approximately 750 F. and holding it at that temperature for a period of from three to five hours.

A second method of fabricating the body 12 or 12 of the unit 10 or 10', respectively, contemplates the forging or casting of the general configuration desired and then strengthening the walls thereof by sealing the opposite ends of the longitudinal bore extending therethrough and applying hydraulic pressure within said longitudinal bore at sufficiently high pressure to exceed the yield point of the material from which the unit is cast or forged. Under this condition the inner wall will be stretched beyond its yield point and enlarged about 6% and the transverse outside dimensions enlarged about 1% so that when the hydraulic pressure is released the inner wall of the unit will be under compression while the outer wall of the unit is under tension. The interface between these compression and tension stresses will be located at a point within the wall of the unit between the inner and outer faces thereof. The interplay between these compression and tension stresses produces a resulting structure which has a higher overall tensile strength than the unit had prior to the hydraulic treatment thereof.

A third method of fabricating the well head assembly can best be understood by reference to FIG. 6. This method contemplates the forging or casting of the body 12a of the well head assembly 10a, the subsequent heating thereof, the insertion of a pre-chilled steel liner into the central bore 14a of the body 12a, and allowing the assembly thus created to return to the ambient temperature. The steel liner then will be under compression and the body 12a Will be under tension. After the unit has been fabricated, and the liner 170 installed in the manner described above, suitable openings 24a, 26a and 28a are formed therein to receive valve assemblies in the same manner as above described.

FIG. 7 discloses a well head assembly 10b comprising a 'body 12b having twin longitudinal bores 14b and 14c extending therethrou-gh and adapted to connect with dual tubing strings (not shown). The bore 141) is intersected by suitable valve receiving openings 24b, 26b and 28b. Similarly, the bore 140 is intersected by suitable valve receiving openings 24c, 26c and 280. A laterally extending bore 16]) connects with the bore 14b and extends laterally through the arm 20b of the body 12b and is intersected by an opening 36b adapted to receive a valve for controlling flow therethrough. A similar bore 18b connects with the bore 140 and extends laterally through the arm 22b of the body 12b and is intersected by an opening 38b adapted to receive a valve assembly for controlling flow therethrough. It will be appreciated that either of the valve bodies 50 and 50 discussed above with respect to FIGS. 4 and 5, respectively, can be employed in the openings 24b, 24c, 26b, 26c, 28b, 28c, 36b and 38b. It should further be appreciated that the body 12b of the unit b can be fabricated in accordance with any of the three methods discussed above with respect to the fabrication of the body 12 of the unit 10.

The structure illustrated in FIG. 8 shows the application of the principals of the present invention to a combined integral tubing head and dual master valve assembly 200. The unit 200 is provided at its lower end with a flange 202 adapted to be connected by suitable bolts 204 to a similar flange 206 at the upper end of the casing head 208. A casing 210 is fixed to the casing head 208 and extends upwardly therefrom and is received within a longitudinal bore 212 formed in the unit 200. A tubing hanger 214 is provided with a suitable downwardly and inwardly tapered surface 216 adapted to be received within and rest on a complementary downwardly and inwardly tapered surface 218 in the bore 212. A tubing 220 is threaded into the lower end of the tubing hanger 214 and is suspended therefrom. The tubing hanger 214 is retained within its seat within the unit 200 by a plurality of radially extending retaining pins 222 having conical inner ends 224 which are adapted to abut a beveled surface 226 formed on the upper edge of the tubing hanger 214.

Suitable laterally extending bores 230 and 232 connect the bore 212 beneath the tubing hanger 214 and the outer surface of the unit 200. Suitable valve receiving openings 234 and 236 extend transversely through the unit 200 and intersect the bores 230 and 232, respectively. The openings 234 and 236 are adapted to receive valves in the manner described hereinabove to control the flow through the bores 230 and 232. Tapered openings 240 and 242 extend transversely through the upper portion of the unit 200 and are adapted to receive dual master valves in the manner described hereinabove to control the flow of fluid through the longitudinal bore 212 in the unit 200. The upper end of the unit 200 is provided with a flange 250 adapted to provide connection with whatever flow handling units (not shown) might be required by any particular installation.

While preferred embodiments of the present invention are described herein, it should be noted that various changes may be made therein without departing from the spirit of the invention as defined in the appended claims.

Having thus described the invention, what is claimed as new and is desired to be secured by Letters Patent is:

1. A well head Christmas tree assembly comprising a one piece body having a lower flange portion for connection to a well tubing head, a straight vertical through bore extending through said body with the lower end of the bore being formed to communicate with the tubing head, a laterally extending branch bore in said body communicating with said through bore, said body having substantially planar front and rear face portions, horizontally extending tapered openings extending through said body at said face portions, one of said openings intersecting the axis of said through bore and another of said openings intersecting the axis of said branch bore, said branch bore being downstream from said opening that intersects said through bore, a one piece tapered valve housing fitting in each of said tapered openings and extending at least from one face portion to the cal other face portion of said body, retainer means for each of said valve housings at one of said body face portions, ports extending through said valve housings and allgned with the associated bores in the body, key means be-.

tween said valve housings and said body for maintaining port alignment, fluid sealing means between said valve housings and said valve body and surrounding said ports, and valve members movably mounted in said valve housings, said valve members having ports alignable with the ports in said valve housings.

2. A well head Christmas tree assembly comprising a one piece body having a lower flange portion for connection to a well tubing head, a straight vertical through valve housing fitting in each of said tapered openings and extending at least from one faceportion to the other face portion of said Christmas tree body, threads on the smaller end of each valve housing, retainer nuts on said threads engaging the associated body 'face portion, ports extending through said valve housings and aligned with the associated bores in the body, key means between said valve housings and said body for maintaining port alignment, fluid sealing means between said valve housings and said valve body and surrounding said ports, and valve members movably mounted in said valve housings, said valve members having ports alignable with the ports in said valve housings.

3. A well head Christmas tree assembly comprising a one piece body having a lower flange portion for connection to a well tubing head, a straight vertical through bore formed in and extending through said body with the lower end of the bore being formed to communicate with the tubing head, a laterally extending branch bore in said body communicating with said through bore, said body having substantially planar front and rear face portions at said bores, a plurality of horizontally extending tapered openings extending through said body at said face portions, at least two of said openings intersecting the axis of said through bore and another of said openings intersecting the axis of said branch bore, said branch bore being downstream from the openings that intersect said through bore, a one piece tapered valve housing fitting in each of said tapered openings and extending at least from one face portion to the other face portion of said body, retainer means for each of said valve housings at one of said body face portions, ports extending through said valve housings and aligned with the associated bores in the body, key means between said valve housings and said body for maintaining port alignment, fluid sealing means between said valve housings and said valve body and surrounding said ports, and valve members movably mounted in said valve housings, said valv members having ports alignable with the ports in said valve housings.

4. A well head Christmas tree assembly comprising a one piece body having a lower flange portion for connection to a well tubing head, a straight vertical through bore extending through said body with the lower end of the bore being formed to communicate with the tubing head, a laterally extending branch bore in said body communicating with said through bore, said body having substantially planar front and rear face portions, a plurality of horizontally extending tapered openings extending through said body at said face portions, at least two of said openings intersecting the axis of said through bore and another of said openings intersecting the axis of said branch bore, said branch bore being downstream from an opening that intersects said through bore, adjacent ones of said tapered openings having their smaller ends at opposite face portions of said body, a one piece tapered valve housing fitting in each tapered opening and extending at least from face portion to face portion of said body, retainer means for the smaller ends of said valve housings at the respectively associated body face portions, ports extending transversely through said valve housings and aligned with the associated bores in the body, key means between said valve housings and said body for maintaining port alignment, fluid sealing means between said valve housings and said valve body and surrounding said ports, and valve members movably mounted in said valve housings, said valve members having ports alignable with the ports in said valve housings.

5. A Well head Christmas tree assembly comprising a one piece body having a lower flange portion for connection to a well tubing head, a straight vertical through bore extending through said body with the lower end of the bore being formed to communicate with the tubing head, a laterally extending branch bore in said body communicating with said vertical bore, said body having sub stantially planar front and rear face portions at said bores, horizontally extending tapered openings extending through said body at said face portions, a plurality of said openings intersecting the axis of said through bore, another of said openings intersecting the axis of said branch bore, said branch bore being downstream from 8. an opening that intersects said through bore, adjacent ones of said tapered openings having their smaller ends at opposite face portions of said body, a one piece tapered valve housing fitting in each tapered opening and extending at least from one face portion to the other face portion of said Christmas tree body, threads on the smaller end of each valve housing, retainer nuts on said threads engaging the respectively associated body face portions, ports extending through said valve housings and aligned with the associated bores in the 'body, key means between said valve housings and said body for maintaining port alignment, fluid sealing means between said valve housings and said valve body and surrounding said ports, and valve members movably mounted in said valve housings, said valve members having ports alignable with the ports in said valve housings.

References Cited in the file of this patent UNITED STATES PATENTS 1,323,660 Thrift Dec. 2, 1919 1,834,128 Langenberg Dec. 1, 1931 1,856,874- Langenberg May 3, 1932 1,971,381 Penick et al Aug. 28, 1934 2,094,812 Penick et al Oct. 5, 1937 2,327,129 Ronan Aug. 17, 1943 2,335,355 Penick et al Nov. 30, 1943 2,442,548 Mueller June 1, 1948 2,604,419 Her benar July 22, 1952 2,621,888 Allen Dec. 16, 1952 2,859,773 Wallace Nov. 11, 1958

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