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Publication numberUS3086590 A
Publication typeGrant
Publication dateApr 23, 1963
Filing dateJun 23, 1958
Priority dateJun 23, 1958
Publication numberUS 3086590 A, US 3086590A, US-A-3086590, US3086590 A, US3086590A
InventorsJr John G Jackson, Allen F Rhodes
Original AssigneeMcevoy Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Apparatus for drilling and completion of inaccessible wells
US 3086590 A
Abstract  available in
Images(6)
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Claims  available in
Description  (OCR text may contain errors)

A ril 23, 1963 J. G. JACKSON, JR, ETAL 3, APPARATUS FOR DRILLING AND COMPLETION OF INACCESS iBLE WELLS Filed June 23, 1958 6 Sheets-Sheet. 1

23 Z4 Z2 WK I //0 ATTORNEY April 1963 J. G. JACKSON, JR., ETAL 3,086,590

APPARATUS FOR DRILLING AND COMPLETION OF INACCESSIBLE WELLS Filed June 25, 1958 6 Sheets-Sheet 2 r 5 V Mm fl w WW wm A N c A nl 23, 1963 J. a. JACKSON, JR., ETAL 3, 0

APPARATUS FOR DRILLING AND COMPLETION OF INACCESSIBLE WELLS Filed June 25, 1958 6 Sheets-Sheet 3 ATTORNEY April 23, 1963 J. G. JACKSON, JR., ETAL APPARATUS FOR DRILLING AND COMPLETION OF INACCESSIBLE WELLS Filed June 23, 1958 6 Sheets-Sheet 4 HVVENTORS abzw yz.

A TTORWE Y April 23, 1963 .1. G. JACKSON, JR., ETAL 3,086,590

APPARATUS FOR DRILLING AND COMPLETION OF INACCESSIBLE WELLS Filed June 23, 1958 6 Sheets-Sheet 5 0 2 m \m x m/m\ a a -i I 1 x: a Z

Mar 7n 6. Jackson, (/f. /4//ex7 F. 5 /700450 INVENTORS ATTORNEY April 23, 1963 J. G. JACKSON, JR., ETAL APPARATUS FOR DRILLING AND COMPLETION INACCESSIBLE WELLS Filed June 23, 1958 WX 207 yaw/1 6? 6 Sheets-Sheet 6 John 6. Z/OCAJOI? dz".

A//e/7 F. Rhodes INVENTORS ATTORNEY United States Patent 3,036,590 AIPARATUS FOR DRILLING AND COMPLETION OF INACCESSIBLE WELLS John G. Jackson, Jr., Angleton, and-Allen. F. Rhodes,

Houston, Tex., assignors to McEvoy Company, Houston, Tex., a corporation of Texas.

Filed June 23, 1958; Ser. No. 743,622 4 Claims. (Cl. 166-665) This invention pertains to underwater wells and to equipment for use in drilling and completing underwater wells. In particular, the invention pertains to casing and tubing hanger equipment for underwater wells, to auxiliary equipment for use with such wells, and to equipment for use in operating and reworking such wells after they have,

been completed.

A principal object of the invention isto provide apparatus solving problems occurring during drilling and completion of underwater wells.

Another object of the invention is to provide casing or tubing such as when the casing or tubing has become stuck.

Another object of the invention is to provide such equipment having connections whereby pressures and/or fluids within the well hanger or suspension equipment and within the well completion equipment are accessible at the surface of the water beneath which said submarine land surface lies.

An additional object of the invention is to provide in such. equipment releasable joint means which can be operated or controlled remote from the equipment, same permitting.disconnection and reconnection of the equipment parts remotely.

Briefly, the invention consists of a lower outer tubular member, within whichthere are arrangeda plurality of concentric hanger or suspension means, each for supporting a casing, tubing or other device in the well. The hanger means are arranged one above the other and progressively support progressively smaller diameter casings or tubings. Several modifications of this equipment are available which can be used alone or in conjunction with the remainder of the equipment.

The casing hangers are such that they can selectively be located in the tubular member surrounding the hanger equipment as the equipment is assembled in stages. The casing and tubing suspending part of the equipment is surmounted by a releasable joint which can connect the tubular member with upper equipment of any type. Usually the connection is made with blowout prevention equipment necessary during drilling operations. At times an auxiliary hydraulic casing hanger capable of hanging a casing or tubing anywhere along its length is provided between said connection and said blowout prevention equipment. Guide meansare provided where necessary to guide equipment to be connected into its proper position.

The blowout prevention equipment is ordinarily used only while the well is-being drilled and tested. Equipment for retaining Well pressures is included below the connection so that the blowout prevention equipment may be removed and a Christmas tree assembly connected at the top of the well. The previously described connection joint at the upper end of the outer tubular member is also used for connection of the Christmas tree to the apparatus:

3,086,590 Patented Apr. 23, 1963 Other objects and advantages of the invention will appear fromzthe following description ofpreferred embodiments, referencebeing made to theaccompanying drawings, of which:

FIGURE 1 isan overall schematic elevation of the equipment, according to the preferred embodiment, shown as disposed in a well. located upon a land surface beneath a bodyof water;

FIGURES=2A through 2D are partial elevations, partlyin verticalsection, of the preferred embodiment, each showinga portion thereof from the upper end tothe lower end of the equipment;

FIGURE 2E is similar to FIGURES 2A-2D, showing a lateral portion of'the equipment;

FIGURE 3 is. an elevation, partlyin verticalsection, showing a part of the equipment asshownin FIGURE 20, some elements beingin moved positions;

FIGURES 4A through 40 are partial elevations of the equipment equipped with an auxiliary casing hanger, each figure showing .a port-ion. of the equipment from the upper end to the lower end;

FIGURES is similar toFIGURES 2C and 3, showing an auxiliaryv element inplace; and,

FIGURE 6 is a partial elevation similar to FIGURE 2B showing a retrieving toolin place.

Referring now to the drawings in detail, and first to FIGURE 1, there is shown a floating vessel 10 at-the-surface of body. of water 11. A well apparatus 12Ih'aving horizontal plate 13 affixed thereto rests at plate 13 upon submarine land surface 14, or bottom, about awell hole' 15. A Christmas'tree 18 surmounts the well apparatus. Two guide lines '19, 20 are wound on powered drums 21,

22 aboard vessel :10 and extend fromthe drums over pulleys 23, 24 to connections 25; 26'of plate'13. Acasing 27 is connected into the lower end of well apparatus 12 and-extends therefrom into the well 15.

Referring now, especially to FIGURES 2A-2E of the drawings, the preferred embodiment of well apparatus 12 includes outer casinghead body 30'at the upper end of which is attached a latched connection receptacle. 31. At the upper end of the receptacle 31 is a guide funnel 32, secured thereto such as by weld 33. The outer casing head body is of elongate tubular form having at its lower end an internal threadformation 34. Thread formation 34 is secured onto threaded upper end 35 of a conductor casing 36. Generally, the conductor casing is lowered into the well, after the initial hole is drilled, with the-outer casing head body andreceptacle 31screwed onto its upper end as described." To handle these elements, an internal annular groove 38 within the receptacle receives a lock' mechanism, not shown, attached at the lower end'of a drill string. A series of radially drilled sets of ports 42-46 have outer threaded ends, into which are screwed pipe connections 50-54 for flow or pressure communication from within the body, are longitudinally spaced along the body at locations to provide access to desirable points after casing and. tubing have been suspended in the body. Each of the longitudinally spaced sets of ports comprise three or'four ports arranged circularly around the body and usually-evenly spaced-therearound.

Above ports 42body 30 has internal annular shoulders 56, 57 disposed to support vertical loads. Above shoulder 57 there is an annular internal recess 58 having-upper and lower conical sides. Above recess 58 there is another annular internal recess 60 also having'upper andlower conical sidesandthereabove an annularinternal: recess 61 having a lower horizoutal'side and an upper conical side.

Above. recess 61, the second ofsaid sets of'ports 43 is disposed. Above. ports 43 there is an annular internal recess 62 having upper and lower conically tapered sides.

Proceeding further up the outer casing head body, there is still another annular. internal recess 63' having upper and lower conical sides, and associated therewith, and thereabove, another annular internal recess 64 having a lower horizontal side and an upper conical side.

Above recess 64 the third set of radial ports 44 is disposed, and above these ports there is another annular internal recess 65 having upper and lower conical sides.

Above recess 65 ports 45 are disposed and thereabove is a further annular internal recess 66 having upper and lower conical sides. Above recess 66 is recess 67 having a lower horizontal side and an upper conical side, and thereabove is another set of ports 46, above which is a recess 68 having upper and lower conical sides.

Recesses 60, 61, recesses 63, 64, and recesses 66, 67 comprise coacting recesses, which cooperate in supporting a separate hanger mechanism. The recesses 58, 62, 65, and 68 each serves to position and lock a holddown means within the outer casing head body.

Above the outer casing head body 30 and within receptacle 31 is a tapered shoulder 70 disposed to receive and support the inserted mandrel portion 71 of the connection at receptacle 31. Above this tapered shoulder is the internal annular recess 38', the lower side of which is conical and the upper side of which is horizontal. A hardened insert ring 72 provides the upper side of said internal annular recess, the ring extending outwardly of the recess in order to enlarge the bearing surface of the upper side of the ring. Above the said hardened ring is another tapered shoulder 73. The guide funnel 32 attached about the uppermost end of the receptacle 31 is provided to guide the mandrel portion of said latch joint into the receptacle. At the outer edge of the guide funnel are two oppositely disposed extension arms 75. 76, which extend outwardly to terminate in vertical sleeves 77 through each of which a vertical guide, such as cable 20, is freely received. The arms 75, 76 are welded to a ring 78 welded around the outer edge of funnel 32, and vertical triangular webs 79, 80 strengthen the arms.

A casing hanger 84 is disposed opposite recesses 60, 61 and 62 within the outer casing head body 30. Hanger 84 is screwed at lower thread formation 85 to the upper end of a string of casing 86. Beginning at the upper end of hanger 84, there is first, an upper formation 87 onto which is screwed a ring 88 of tubular shape and having an inner upper chamfered entrance 89. The upper tubular part 90 of the hanger is of smaller diameter than the internal diameter of body 30.

Below this upper tubular part 90 of the hanger, the hanger enlarges to be closely fitted within body 30 at 91. A packing or sealing recess 92 has a ring 93 of resilient elastomeric material disposed therein, the lower surface of which is beveled to fit conical upwardly facing shoulder 95, the ring 93, when uncompressed, extending below the shoulder to provide a part to be compressed when a seal is to be formed.

Below shoulder 95 there is an outwardly reduced hanger portion 97 around which a tubular sleeve 98 is received. Portion 97 terminates downwardly at a downwardly converging conical surface 100 below which is a tubular hanger portion 101 of thin walled form. Portion 101 terminates downwardly at a thickened wall portion 102, the lower end of which has threaded socket 85 engaging casing 86. A ring-shaped nut 103 is beveled at its lower edge. The lower part of the nut is inwardly recessed to permit the nut to move over hanger portion 102, A shear pin 105 (shown sheared) is received through nut 103 and into a tapped opening in hanger portion 102 to hold nut 103 in that position while the equipment is lowered into the well.

Sleeve 98 has therearound a plurality of window openings 106, only one of which is shown, through each of which is disposed a latch 107. The latches are spring biased radially outwardly by helical compression springs 108 disposed in recesses at their inner sides. Upper and lower annular protruding portions 110, 111 of the latches correspond in shape and dimensions with recesses 60 and 61, respectively, but are of such proportions that they will not enter any recesses thereabove.

The upper end of sleeve 98 acts to compress the part of ring 93 extending below shoulder when ring 93 is not compressed to form a seal around the hanger within body 30. Around the reduced upper portion 90 of hanger 84 there is a ring shaped member 114 having an L-shaped vertical section. The vertical part thereof has a plurality of window openings, 115 therearound, only one of which is shown, through which are disposed a plurality of pins 116 having outer dimensions and shape corresponding to recess 62. A stepped sleeve member 117 is of relatively large diameter at its upper part 118 and of smaller diameter at its lower part 119, and the lower part acts to move pins 116 outwardly through their windows 115 when sleeve 117 is moved downwardly thereagainst. The lower end of sleeve part 119 is conically tapered to provide a guide surface to engage the bevel of pins 116. Near its upper end sleeve 117 has internal annular recess 121 having upper and lower conical sides. The upper end of sleeve 117 is internally beveled. The lower end of element 114 is sealed outwardly and inwardly by O-rings 122, 123 to body 30 and to hanger 84.

In using this device to suspend a string of casing 86, the casing is screwed into the lower threads 85 of the hanger. The inner sleeve like portion of hanger 84 is in such a position that lower portion 102 is received within the interior recess of nut 103. In this position intact shear pin engages both the nut and the lower portion of the casing hanger. With the hanger so arranged, the latches 107 are permitted to move freely to a retracted position within the window openings 106 of sleeve 98. The helical springs 108 behind the latches tend to force them in an outward direction through the window openings, but at the same time permits the latches to be forced back into retracted positions within the window openings when the casing hanger is lowered through a restricted opening. The latches on being lowered through the body 30 pass the upper recesses as will be described, because of the particular selected shape of the latches and the upper recesses. After latches 107 have entered recesses 60, 61 further lowering of casing 86 and hanger 84 shears pin 105, because of the casing weight, and hanger 84 moves downwardly relative to latches 107 until sleeve '98 is in a position surrounding recess 97 of the hanger. In this position of the hanger the latches 107 are fully backed up by the hanger so that they can not be moved out of the recesses. At the same time, sleeve 98 compresses packing ring 93 to form a seal around the hanger.

The combined hanger and easing string assembly is lowered into the well bore and easing head body 30 with an auxiliary string of pipe, not shown, which connects to the hanger by engaging recess 121 of sleeve 117. As the apparatus is lowered the weight of the casing is transmitted by the lower shoulder of upper ring 88 onto the shoulder formed by the step portion of sleeve 117. Once the hanger latch mechanism has received the entire weight of the casing string, further downward motion of the casing string is stopped. Further downward motion of the auxiliary string then forces sleeve 117 downwardly causing holddown pins 116 to be urged radially out wardly into recess 62 by lower portion 119 of sleeve 117. Toward the end of the downward travel of sleeve 117 the engaging mechanism which connects the sleeve to the auxiliary string of pipe is automatically disengaged as will be described later. This completes the casing suspending procedure and permits retrieving the auxiliary string and engaging mechanism.

Recesses '66, 67, 68 receive latches 125, 126 of hanger 127. Hanger @127 is very similar to hanger S4. The thickened lower tubular portion 102 of hanger 84 is absent from hanger 127. The sleeve 128, corresponding to sleeve 98 and not 103 of the lower hanger are integral in form and there is no lower recess for engaging the lower part of the hanger. The elastomeric sealing ring 130 corresponding to ring 93 of hanger 84 is 'not'inwardly' of the holddown latch sleeve 133 is somewhat like the lower end of sleeve '117, having; lower offset portion 135 of smaller diameter inwardly and outwardly than the upper part 136 of the sleeve. A ring '137 of L-shaped vertica-lsection has a plurality of window openings 138 to receive the ends-of pins 126 of outward-shape corresponde ing with recess68. The sleeve portion 135 serves to drive pins 126 outwardly when the sleeve is lowered relative to ring 137. The beveled. surfacesa-re provided as before. The upper part 136 of sleeve 133 is of'elongate tubular form and terminates" upwardly at a pair of inwardly protruding annular rings 14-1, 142 between which is formed a recess 143 having. upper and lower conical si-des,.this latter'recess being. for receiving. the latching mechanism of the auxiliary string. heretofore mentioned and used for running equipmentinto the well. Screwed to the upper threaded portion 145 of hanger 127 is an elongate tubular element 146. At the lower end of this element is a set 147 of radially drilled holes providing communication between the inner portion of the tube #146 and a similar space formed by the outer portion of the tube 146 and an outer tubular sealelement 148 which is welded to the outer portion of said tube. A tapered shoulder 1'50' disposed to support the weight of a string of tubing 151 is positioned above the radially drilled holes. Above the tapered shoulder is an internal annular recess 153, both sides of which are conical in shape.- Further up the elongate tubular element 146 are two sets of radially drilled holes 155, 156. The lower set of'holes 155 provide communication between the inner portion of the elongate tubular element and the annular space therearound previously described. The upper set of holes 156 provides communication between the inner portion of the tube and the outer portion outside of element148. A tapered shoulder 157, an internal recess 158 with a lower conical side and an upper horizontal side, and tapered sealing shoulder 159, all located on the upper portion of tubular element 146, form a latch joint connection receptacle similar to receptacle 31, previously described, but smaller in diameter.

A body 170 for suspending an auxiliary casing hanger is supported within outer casing head body 30 at recesses 63, 64, 65. This body is similar to hangers 84 and 127, the lower portions being like hanger 127 and the upper portions being like hanger 84. Internally, body 170' has annular recess 171 having upper and lower conical sides, upwardly facing downwardly converging conical seat surface 172 and thereabove seat recess 173 having a lower conical surface. The upper end of bodyv 170 is internally chamfered to provide for entrance thereinto. An O-ring 174 around the upper end ofbody 179 provides a seal between body 170 and body 30 to supplement the resilient seal of the hanger latching assembly. A holddown body 176latched in recess @Sfunctions the same as the holddown assembly of hanger 84. Body 176 has a cylindrical vertical axial opening therethrough. The upper outer part 1177 of body 176 is recessed, providing a thin walled upper tubular portion of the body, a lower uprwardly facingrecess 178, and-a plurality of window openings 179 in the outer side of the recess. Openings 179 are positioned to register with recess 65, so that the pins 180 may be urged into the recess. 'A sleeve 182 has lower skirt portion 183 tapered at its lower end for engaging the upper tapered surfaces of the pins. Pins 180'are urged radially outwardly when sleeve 182 is moved downwardly relativ-e'to recess 178. Aninternal recess 184 is provided for engagern'entby a suitable toolfor lowering the sleeve.

Apparatus for-supporting and holding in place the string:

of production tubing 151 is attached to the top of the production tubing by means of a threaded connection of usual form. Support is provided by tapered ring 188 restingon tapered shoulder 1500f the tubular tubing hanger head 146. The weight of the tubing string rests partially upon the tapered ring and partially-upon the resilient elastorneric sealing ring 189, which axially compresses. ring 189 and effects a pressure tight seal around the tubing hanger 146. The axial compression of the sealing'ring is limited by the vertical height of its recess. T he tubing hanger apparatus includes a sleeve I191'in which -are'-window openings 192. Holddown latch lugs 193 are arranged to project through the window openings and en gage in annular recess 153 within the tubing hangerbody- 1%. Lugs 1593 are moved through the window'openingsand into the recess by the axial travel of inner sleeve 1% within the tubing hanger;

Downward motion of'said tool shears pin 198-and moves sleeve 195 in a downward direction, thus forcing. the

latching lugs into an engaged position. The tubing string hanging apparatus is lowered into position in the hole by means'of an auxiliary, tubing string of usual form which engages the hanger in the left-hand threaded connection 2910f an upper sleeve 202 which is threadedly' connectedto sleeve 191 at 203. After thetubing hanger'mechanism has beenlowered into position and the holddown latch lugs engaged, the auxiliary string: of tubing is disengaged from the left-handed threaded'connection and removed:

Controlled communication to the annular space between production tubiug 1-51 and production casing .131

is provided by a spring actuated sliding valve mechanism attached to the upper portion of the tubing hanger sleeve 202. The sliding valve mechanism is comprised of sliding cylindrical sleeve 205 which has a tgroove 206 around its outer surface together with threev smaller grooves 207, 208 and 209 in each of which-is'disposed anO-ring seal. When the mandrel portion'of a latch joint (to be described) at the upper end of the tubing hanger set is not engaged within the receptacle, the" slide valve is held in its closed position (not shown) by helical spring 210: When the mandrel 21 1 is engaged within the receptacle it urges sleeve 205 downwardly to compress spring 210 and'thereby bring recess 2% into register with both ports and 156 to open the valve as shown) and permit communication between said tubing-casing annular space and the annular space between outer. body 30 and sleeve 146. Therefore, a valve means isprovidedwhich is automatically opened when means for receiving or controlling flow from the well is in place thereabove, butwh-ich is automatically closed when such flow receiving'or controlling means is removed, so that the well is under control at all times.

As mentioned earlier, a connection or joint (including receptacle 3 1) which can 'be controlled from a remote point is disposed above the outer casing. head body 30. Asmaller joint also connects the upperendiof the tubing hanger assembly to means for receiving flow from the tubing. These two connections :are verysimilar but differ in. some respects because of'their size, it usually being the case that the tubing joint is of sufliciently smaller size that it can be made of ste'el'of suflicient hardness topertor-m1 the necessary function, while the largercasing joint is of such size that it mustbe madeof cast steel which lacks the necessary hardness. The receptacle 31 Downward travel "of the inner sleeve forces the lugs outward by tapered engagement having internal recess 38 and hardened steel ring 72 has already been partially described. The joint connection is made by engagement of the latch lugs 220 within the receptacle recess 38. The mandrel 71 consists of an outer sleeve 221 in which are a plurality of circularly spaced window openings 222. A plurality of latching lugs 220 each rest in one of these openings and are held in position by cantilever type finger springs 225. These springs exert a force tending to push the latching lugs into an extended position through the window openings. Springs 225 are integrally formed as downwardly extending members from a ring 226 which is bolted in place against shoulder 227. The finger springs extend downwardly therefrom to alignment with the window openings. Each latching lug comprises a central body portion freely moveable through a Window opening and opposite side car parts 228, or flanges, which extend to either side of a window opening to prevent the lugs from being pushed completely through the opening. Bars 228 have lower tapered surfaces 230 which are positioned, when the lug is engaged in recess 33, to be engaged by upper tapered surface 231 of a releasing sleeve 232 which is initially held fixed with respect to sleeve 221 by frangible pin 233 which extends through sleeve 221 into a suitable hole in sleeve 232. v

A seal is provided around the upper end of sleeve 221 by the sealing ring 235 disposed between a support ring 236 and a compression ring 237. Compression ring 237 is screwed onto thread formation 238 at the upper end of sleeve 221 and support ring 236 is held in place by a shoulder. The receptacle 31 has the upwardly facing conical shoulder 73 to engage a corresponding conical shoulder of support ring 236 and the form of sleeve 221 and its seal assembly are such that ring 236 engages surface 73 to cause the support ring to be moved toward the compression ring when sleeve 221 is in place. An O-ring 240 in a suitable recess around sleeve 221 provides an auxiliary seal therearound.

An inner sleeve 24 2 is attached to the outer sleeve at threaded connection 243. The inner sleeve serves the function of protecting the latching lugs and finger springs from damage by tools and equipment which pass through the bore of the mandrel. A retaining nut 244 with a downward tapering lower end attaches to the lower portion of the outer sleeve of the mandrel and seats on the tapered shoulder 70 of the latch joint receptacle 31 when the two are connected.

The smaller latch joint is the same as the larger one except that in the arrangement shown with the double wellhead connection, a releasing ring 245 is installed within the retrieving sleeve 232 of the larger latch joint. Ring 245 engages in a recess 246 of the releasing sleeve 232 of the larger joint mandrel and surrounds the tubing connection 247 and rests on ring 248 which is held in position on the smaller latch joint mandrel by a set screw and by a compression ring 250. Ring 245 is held clamped in recess 246 by the upper surface of retaining nut 244 until such time as pin 233 is sheared to release the connection. Connection of the smaller latch joint is effected in the same manner was that of the larger joint. The double connection, including both latch joint connection assemblies, is lowered into position with a Christmas tree assembly 251 bolted to the upper flange 252 atop the double wellhead connection. The side outlet 265 of the double connection usually provides access to the an nular space between tubing and easing. A seal between the inner and outer tubular sections of the double wellhead connection, is provided by a chevron packing 255 compressed by a compression ring 256 screwed into an adapter 257 screwed into the upper portion of the outer sleeve 258. When the double wellhead connection 1s lowered into position the outer latch joint is held in a relative position slightly lower than normal by the Belleville or washer spring 260 between compression ring 256 and a spacer ring 261 surrounding tube 262 below flange 252. The outer, or larger, latch joint mandrel is, therefore, fitted in its respective receptacle 31 first and is latched into position and sealed. Further downward motion of the Christmas tree assembly compresses spring 260 and brings the inner latch joint mandrel into lateral position at recess 158, a seal being provided by seal 264 corresponding to seal 235 of the larger joint. With double connection thus thaving been made, production of the well through the tubing is controlled and sealed by the smaller latch joint connection and is routed directly to the Christmas tree valve assembly. The access to measure pressure and control of fluids within the annular space between production tubing and casing is further provided by means of the automatic slide valve provided at ports 155, 156 and the valved side outlet connection 265 on the outer sleeve of the double wellhead connection.

Latches 158, 220 are remotely operable, as has been stated. By this it is meant that through use of a handling string connected at one end to the latches as described, suitable operation of the handling string at its end remote from the latches will cause latching or unlatching of the latches, as desired.

Release of the double wellhead connection is accomplished by lowering a retrieving tool into the inner bore of the latch joint mandrel. The retrieving tool engages the releasing sleeve 266 of the smaller latch joint mandrel at annular latching groove 267 thereof. Upward motion of the retrieving tool raises the releasing sleeve of the smaller latch joint connection which engages the tapered surfaces of the latching lugs and causes them to be retracted out of recess 158. With the latches thus in a retracted position, further upward motion of the retrieving tool causes the mandrel to be removed from the receptacle. As this takes place the upward motion of the mandrel exerts a force through ring 245 upon the releasing sleeve 232 of the larger latch joint. Upward force exerted on the latter releasing sleeve shears pin 233 and retracts latching lugs 220 so that the entire double wellhead connection can be removed. These remote-controlled latched connections or joints are more fully disclosed in our copending application for United States Letters Patent S.N. 743,741, filed June 23, I958, and entitled Pipe Connection, which also discloses the retrieving tool mentioned above.

As has been described, the outer casing head body 30 is threadedly connected to the receptacle 31, the connections being at threads 271. These parts may be made integral if desired. At the lower end of receptacle 31 the horizontal plate 13, in a plane perpendicular to the axes of body 30 and receptacle 31, is affixed to the receptacle such as by welding. The plate 13 is usually circular but may be otherwise as desired. Plate 13 has a central circular opening 270 through which the lower end of the receptacle is received. Plate 13 serves to provide a bearing surface to rest upon the submarine land surface 14 to provide support for the equipment. However, the equipment is, of course, primarily supported by the cementing of the casing 36 in place in the well.

Spaced from the receptacle and mounted upon the plate 13 there is a cylindrical valve body 275 (FIGURE 2E) having its axis vertically disposed. Body 275 has a concentric opening 276 within which is disposed a ported plug element 277. A funnel 278 forms the upper end of body 275. Body 275 and the internal elements thereof are disclosed in full in our co-pending application for United States Letters Patent S.N. 743,907, filed June 23, 1958, and entitled Multiple Valve and Connection, now United States Patent Number 2,990,851, issued July 4, 1961. Opening 276 may be plugged by a blank plug replacing element 277, the details of all of which are shown in said patent. Body 275 and its other elements serve to control fluid flow between pipes 5054, any number of which may be provided, and the pipes or hoses such as hoses 280-284,

which extend from body 275 to a control point at the water surface or. elsewhere. Flow through pipes 50-54, and through any other such pipes, is controlled by the hydraulically operated valves 286-290 to which hydraulic fluid. for their operation is supplied through manifold pipe 292,v the hydraulic fluid beingsupplied thereto through pipe or hose 293.

As. has been stated hereinabove, ports 42-46 and pipe connections 50-54 screwed thereinto, are provided for flow or pressure-communication from within body 30. Also as has been explained, fluid in pipes 50-54 is controlled'byvalves'2'86-290,- the latter 'being hydraulically operated by hydraulic fluid supplied through manifold pipe 292. and conduit 293. Pipe connection 50' leads from ports 42v communicating through the lower end ofbody 30=with the interior of conductor casing 36. Pipe connection 51. leads from ports 43 communicating with the interior opening of body 30 at a location bounded by O- ring seals 122, 123 and packing'ring 93, whereby leaking of any of these seals may be determined. Pipe connection.52 leads from ports 44 communicating with the interior of body 30 between seal 174 and the hanger packing ring therebelow, thereby enabling detection of. leaks of either of these seals; Pipe connection 53-leads from ports 45 communicating with the interior ofbody 30 for detection of leaks of sealsabove and below ports 45. Pipe. connection 54 leads from ports 46 for detection of leaks at the O-rings above the. ports and the packing ring therebelow. It will be noted that leak detection means are provided between adjacent casings-and tubings in the well.

. It will be noted that valves 286-290 must be operated simultaneously by pressure offiuid delivered from pipe 292 unless valves 286-290 are operated by distinct pressures which may be appliedstepwise.

Referring particularly to FIGURES 4A-4C of the drawings, there is shownalternative or supplementary means by which casing 86" maybe supported within casing head body 30* should the casing become wedged or stuck in the hole before it has reached bottom during assembly of the apparatus. The means used to' provide the casing support is similar to a Wrap-arounds lip type casing hanger and is fully disclosed in our copending application for United States Letters Patent S.N. 743,784, filed June 23, 1958, and entitled Pipe Hanger. The body 300 of the hanger is split into two halves having a small latch mechanism-which acts to hold the halves together as is customary in the case of wrap around type hangers having a hingeat one hanger joint and a latch at the other hangerjoint. However, a latch is provided at each side of the division of the hanger body into halves and. no hinge between the hanger halves is provided. The two halves .of the split type casing hanger are inserted into a hydraulic hanger setting mechanism 302. This mechanism holds and supports each hanger half bya pin 303 extending through a perforation of a bracket 304 attached to the upper side of the hanger half; Pin 303 is in aplane perpendicular to the diametric split of the hanger such that each hangerhalf may be pulled therefrom by movement in a direction along the pin axis. A secondpin 307 holds the slip elements 308ofeach hanger half in position until the hanger halves are latched around the casing to be supported. 'When it becomesde= sirable to support'a string of easing, or tubing, extending through the hanger setting means and into the well bore, the hanger setting means is actuatedby hydraulic pressurerapplied from a remote source through pipe 310. This pressure acts on piston 311 within cylinder '312 to cause the hanger-support body315 to be forced inwardly toward the pipe. The two casinghanger. halves'are forced around the pipeand become joined to one another by meansof latches. 301. Pressure is then released from behind piston 31 1 andpressure is applied to the other side of the piston through pipe 316 which causes hanger support body 315 to be retracted. With the hanger halves latched together'around the pipe and'no longersupported bystheihanger. support body, the hanger assembly is then free to. slide down-the outer surface of the pipe until it seats ruponia shoulders:suchrasushoulders 56 and 57. With 1 the hanger assembly thus supported, casing weight is apslip type hangers may be used-or any-non-wrap around hanger. may be adapted and shoulders 56 and 57 may be adaptedcorresponding, to. the hanger which is used.

With a casing, or tubing supported in this manner, its upper. portion above the hanger can then be removed by means of any suitable internal milling or cutting devices:similar to those used in conjunction with fishing tools;. Casing string 86 shown in FIG. 4C illustrates this means of support. After suspension and cutting have beencompleted and the upper portion of the casing has been removed, at holddown. means 320 is installed and latchedin position. Means 320 is substantially identical with:.holddown latch means '116, and associated parts, previously. described. Seats or shoulders 172, 173 of sleeve may be similarly used to support a slip type casing hanger'for suspendinga' stuck casing, such as casing2131.

Thehydraulic casing hanger setting means is a device usedto'ilatch conventional slip type casing hangers around a' stringof pipe extending through the wellhead assembly. It is:attached to the casing head body by means of the latch joint connection as shown in FIGURES 2A-2B. ltisa separate unit with flanged or threaded connections at its upper andlower ends. In use, it is usually attached to the man'drel. portion-2580f the latch joint connection at-its lower. end and to the bottom portion of a blowout preventer assembly (not shown) at its upper end.

To provide controlover pressures and fluids within the well; a sealingplug 322is used when it becomes necessary or desirable to remove the blowout preventer assembly from the casing.head body, either before drilling is completed or when the. Christmas tree 18 is to be installed. The seal plug is illustrated'in FIGURE 4B together with a-seali ng plug and/or casinghanger retrieving tool 323-. The sealing .plug 322'is comprised of a sleeve 324 having a plura-lity of circumferentially spaced window openings 325 throughlwhich extend a plurality, of latches 326, only one of-which is shown. These latches engage in annular recesses 6(, 67, each being forced outwardly through the window openings by the action of a helical spring 327. Theengagement'of these latches in the recesses positions the sealing plug and gives it support in this position. A' second sleeve 328'having a plurality of circumferentially spaced-window openings is positioned above a seal ring 329 and providesmeans for holding the sealing plug in place. With the weight of the sealing plug being supportedby-latches 326, the latch sleeve 330 'is forced downward, forinstallation, by a setting tool (not shown) which engages the latch .sleeve at recess.331. Downward motion-of latcliinggsleeve 330'forces lugs 333 through the window openings of sleeve 328" and'causes them'toengage in annular recess 68. Engagement of'these lugs within recess 68 forces sleeve 328 in a downward direction by action of the tapered upper surfaces of the lugs and causes sleeve 328 to exert an axial compression force on seal ring 329 which is of a resilient elastomeric material such as synthetic rubber. With sealing plug 322 thus latched into position, further downward travel of the setting string releases the setting tool from engagement with the latching sleeve at recess 331. The setting string and tool can then be removed from the well. Aback pressure valve 334 is providedwithin the sealing-plug-.- The valve stem 336 extends beyond theupper end of an adapter 337 screwed into the upper end of the sealing plug body 338'such that when a solid object such as the retrieving 1 1 tool 323 is lowered into position the valve 334 is forced in a downward direction against the action of helical spring 340 and allows fluid or pressure below the sealing plug to pass through the valve and be released to the surface.

Operation of the sealing plug and/or casing hanger retrieving tool 323 provides a means of releasing and retrieving the sealing plug 322 or casing hanger 84 or 127. The retrieving tool 323 includes an outer sleeve 342 in which there are a plurality of circumferentially spaced window openings 343. Freely disposed within these window openings are latching pins 344. An inner sleeve 346 is threaded at its upper end into a spring retaining adapter sub 347 which in turn is screwed onto the lower end of a pipe string (not shown). The adapter sub has a lower shoulder engaging the upper end of helical compression spring 348, the lower end of which engages the upper surface of an inwardly protruding flange 349 at the upper end of sleeve 342. Flange 349 can slide along the upper part of inner sleeve 346 above shoulder 350 thereof. Between shoulder 350 and the lower end of inner sleeve 346, there is a recess 352 for receiving the inner parts of the latching pins when sleeve 342 is up relative to the inner sleeve 346.

In operation, the retrieving tool 323 is lowered into position on a pipe string. Pins 344 come to rest on the upper conical surface 353 of latching sleeve 330. Downward force exerted by the pipe string causes inner sleeve 346 to move down relative to the outer sleeve 342 compressing spring 348 and registering recess 352 behind latching pins 344. At this point, the downward force applied to the latching pins against tapered surface 353, of the latching sleeve forces the latching pins back into recess 352. When this occurs outer sleeve 342 is forced down until it is supported at its tapered shoulder 354. In this position the latching pins of the retrieving tool register with and enter recess 331. Release of the downward force exerted by the pipe string upon the retrieving tool permits inner sleeve 346 to rise to its normal position, thereby forcing latching pins 344 into recess 331. With the retrieving tool thus latched in position downward force can be exerted by the pipe string which will open back pressure valve 334, the force exerted by the lower end of inner sleeve 346 acting in a downward direction on the valve stem 336 of the back pressure valve. Any pressure or fluid built up below the sealing plug is allowed to drain into the pipe string through passages 355 in the lower end of sleeve 346.

To remove the valved plug 322 or a casing hanger from within body 30, the handling pipe string is raised, which through engagement between the retrieving tool and plug latching sleeve 330 raises the latching sleeve and upward travel of the latching sleeve brings offset shoulder 356 on the sleeve into contact with shoulder 357 of the plug body 338. This upward force is then transmitted through the body and into sleeves 324 and 328. Upward force exerted against these sleeves is a retracting force on latching lugs 326 and 333, retracting them into the window openings and thus permitting the sealing plug to be removed from within the casing head body.

The casing hanger setting tool 360 is illustrated in FIGURE 6. It can be used to set the casing hangers 84 and 127, sealing plug 322, plugs set in body 275 for controlling flow through annular access connections 50-54, and inserts and other devices within the casing head body 30. Since its other uses will be obvious, it will be described only in connection with setting of the string of casing 131 and the casing hanger 127 therefor. The tool 360 consists of an outer sleeve 361 attached to a handling pipe string 362 at its upper ened by means of a threaded pin and socket connection 363. The lower end 364 of this sleeve is relatively thin walled and has a plurality of circumferentially spaced window openings .365. In operation, latching pins 366 each extend through one of these openings to engage the hanger latching sleeve 12 136 at recess 143. The latching pins are held in the engaged position by a latching pin sleeve 370 held in position by shear pin 371 (shown sheared). An inner sleeve 372 is attached to outer sleeve 361 by means of a threaded connection 373. The casing string and hanger (screwed together as shown in FIGURE 2D) are lowered into position by the setting tool and pipe string pin 371 being intact and sleeve 370 slightly down from its position in FIGURE 6. When the selective latches of the casing hanger 127 engage their corresponding recesses 66, 67 within the casing head body, support of the casing and hanger is transferred from the setting tool and pipe string to the latches which are in turn supported by the casing head body. Further downward motion of the pipe string and setting tool forces latching sleeve 133 (see also FIGURE 2C) in a downward direction which in turn extends latching pins 126 into engagement with recess 68. Near the end of the downward motion of latching sleeve 133 the latching pin sleeve 370 of the setting tool comes to rest upon a shoulder 374 of the inner casing hanger body 146. Further downward motion causes pin 371 to shear and the outer and inner sleeves 361, 372 of the setting tool to move in a downward direction relative to the shear pin sleeve 370 of the setting tool. At the end of this downward motion the recessed outer diameter 376 of the latching pin sleeve 37 0 is registered with the window openings 365 of the outer sleeve and the ring snap spring 377 in a groove around the inner sleeve is brought into position below the bottom end of the latching pin sleeve. The snap spring is permitted to extend to outside its recess and thus supports and prevents the latching pin sleeve from returning to its relative down position. With the latch pin sleeve in this relative up position, the latching pins 366 can then be forced back into the recess allowed by reduced diameter 376, and upward motion of the pipe string 362, therefore, disengages the tool from the latching sleeve 133 of the casing hanger pipe string and the setting tool can then be removed from the well.

The Christmas tree 18 consists of a flanged master valve 380 connected to the upper flange 252 of the wellhead by a bolted flange connection. Above the master valve is connected a flanged sweep T 381 to the side outlet 382 of which is connected the wing valve 253 by a bolted flange connection. Both master valve 380 and wing valve 253 are operated hydraulically by remote means. From the wing valve, a production flow line 384 is laid, connection being made by a section of flexible conduit means such as hose included in the line to wing valve 253 while the equipment is above the water surface. Flow line 384 extends from the wing valve along the floor of the body of water to a point of accumulation or storage such as a tank battery (not shown), which can be on shore, on a platform, in the water, or submerged below the water surface. If so desired, a remote operated valve can also be connected to annular connection 265 and a pressure line can be connected to this valve and extended to the tank battery along with the flow line. Such line would provide means of investigating the annular pressure between tubing 151 and casing 131 for bleeding off as necessary.

Connected to the top outlet 386 of the flanged sweep T is a tubular extension 387 of sufficient length to permit insertion of wire line tools of various design. At the top of this tubular extension (not shown) is connected a latch joint receptacle (not shown) similar to latch joint receptacle 31. Attached to the upper entrance of the latch joint receptacle is a guide funnel similar to, but smaller than, guide funnel 32. A blank plug is ordinarily inserted into the latch joint receptacle to contain normal well pressures. If it becomes desirable to insert tools or other devices into the inner portion of the production tubing by wire line means, said blank plug can be removed and a small blowout control assembly attached to the upper end of the tubular extension by means of the latch joint. The remote operated master valve 380 is closed during this process to contain well pressures. The wire line tools can then be inserted into the tubular extension. The blowout control tools can then be closed around the wire line and the master valve can then be opened to permit insertion of tools into the tubing bore. The wing valve 253 is kept closed during this operation. This means of entrance is also used to set blank sealing plugs such as plug 388 (FIGURE inside the tubing and to insert retrieving tools to release the latch joint connections to facilitate removal of the Christmas tree assembly.

O-ring seals such as seals 207-209, 122, 123 are provided at other points than have been specifically described and are indicated in the drawings. Such seals may be provided at other points in the apparatus as a person skilled in the art can readily select and a detailed description thereof is not believed necessary.

Where shear pins such as pins 371, 198, 105 are indicated in the drawings as already sheared, it will be obvious that such pins were initially intact and the parts connected thereby were initially in positions indicated by the intact conditions of the pins. Where shear pins such as pin 233 (FIGURE 2B) are indicated in the drawings in intact condition, it will be obvious that such pins can be sheared and the connected parts moved as indicated by the structure.

It will also be obvious that some of the parts described may be included in or omitted from the apparatus as desired.

While preferred embodiments of the invention have been shown and described herein, many modifications thereof may be made by a person skilled in the art without departing from the spirit of the invention, and it is intended to protect by Letters Patent all forms of the invention falling within the scope of the following claims.

We claim:

1. Completion apparatus for wells located in relative- 1y inaccessible locations, such as beneath the surface of a body of water, comprising tubular body means at the upper end of the well having plural vertically spaced hanger support means therewithin, plural pipe hanger means each supported within said tubular body means at one of said hanger support means of said body means and each supporting one of plural well pipes extending concentrically below said tubular body means into the well, first and second upwardly extending concentric tubular elements above said body means, the uppermost of said plural pipe hanger means including additional hanger support means, additional hanger means supported at said additional hanger support means and supporting an additional well pipe extending concentrically below said tubular body means into the well, said additional hanger means also having first releasable connection means connecting said first upwardly extending tubular element thereto, second releasable connection means mounted atop said tubular body means and connecting said second upwardly extending tubular element thereto, said first and second tubular elements also being releasable at their respective described connections, and resilient means biasing said second tubular element downward with respect to said first tubular element while their re spective connections are disconnected whereby said second connection means connects with said second tubular element before said first connection means connects with said first tubular element when same are brought together for connection.

2. Completion apparatus for wells located in relatively inaccessible locations, such as beneath the surface of a body of water, comprising a vertically elongate unitary b y disposed at the upper end of a well and having a vertical passageway therethrough, connection means secured to the upper end of said body having a continuation of said body passageway therethrough, plural vertically spaced supporting seat means in said body along said passageway thereof, plural pipe hanger means disposed in said body passageway each supported upon one of said plural vertically spaced supporting seat means, plural concentric well pipes each supported by one of said plural pipe hanger means and each extending below the hanger means into the well, relatively larger of said well pipes being supported by hanger means disposed lower in said passageway than hanger means supporting relatively smaller of said well pipes, means associated with each said hanger means for anchoring each said hanger means in its supported position in said passageway, the uppermost of said plural hanger means including an interior seat for supporting an additional hanger means, an additional hanger means seated at said interior seat and supporting an additional well pipe extending therebelow into the well concentrically through the well pipe supported by said uppermost of said plural hanger means, said additional hanger means having connection means at its upper portion, first tubular conduit means connected at its lower end to said connection means of said additional hanger means and extending thereabove to form a continuous flow passage therewith, second tubular conduit means connected at its lower end to said connection means secured to the upper end of said body and concentrically surrounding a lower portion of said first conduit means, sliding seal means between said first and second conduit means spaced upwardly from their said lower end connections, means biasing said second conduit means downwardly relative said first conduitmeans, said first and second conduit means lower end connections being releasable, elongate means for releasably engaging said first conduit means lower end connection at its lower end whereupon when its upper end remote from said releasable engagement is suitably manipulated said first conduit means lower end connection is released, said second conduit means lower end connection being released in response to release of said first conduit means lower end connection, whereby said first and second conduit means lower end connections may both be released by manipulation of said upper end of said elongate means remote from said connections.

3. The combination of claim 1, said hanger support means being annular recess means and said hanger means including hanger body means having extendable and retractable means engaged in said recess means, and each said hanger means including additional extendable and retractable means cooperating with said recess means for locking said first named extendable and retractable means in engaged condition in said recess means.

4. The combination of claim 3, said first upwardly extending tubular element including Christmas tree means at its upper end for controlling fluid flow from said additional well pipe connected therewith at said first releasable connection means.

References Cited in the file of this patent UNITED STATES PATENTS 1,927,190 Stephens Sept. 19, 1933 2,187,839 Penick et al Jan. 23, 1940 2,197,920 Brown Apr. 23, 1940 2,512,783 Tucker June 27, 1950 2,714,423 Hitchings Aug. 2, 1955 2,808,230 McNeill et a1. Oct. 1, 1957 2,862,560 Bostock et al Dec. 2, 1958 2,894,586 Schramm et al July 14, 1959 2,917,281 Kofahl c Dec. 15, 19 59

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Referenced by
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US3199595 *Dec 28, 1961Aug 10, 1965Shell Oil CoSecondary control system for underwater wells
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Classifications
U.S. Classification166/348, 285/920, 175/7, 166/366, 166/368
International ClassificationE21B33/043, E21B33/035
Cooperative ClassificationE21B33/043, E21B33/035, Y10S285/92
European ClassificationE21B33/043, E21B33/035