US3265409A

US3265409A - Well completion equipment

Info

Publication number: US3265409A
Application number: US237959A
Authority: US
Inventors: Robert L Crain; Jr Elwood K Pierce
Original assignee: Gray Tool Co
Current assignee: Vetco Gray LLC
Priority date: 1962-11-15
Filing date: 1962-11-15
Publication date: 1966-08-09
Anticipated expiration: 1983-08-09

Description

mg. 9, 1966 R. L. GRAIN ETAL 3,265,409

WELL COMPLETION EQUIPMENT Filed Nov. 15, 1962 6 Sheets-Sheet 1 MMJMM Y A g- 9, 6 R. CRAIN ETAL wELL COMPLETION EQUIPMENT 6 Sheets-Sheet 2 F iled Nov. 15, 1962 ENTORS' ATTORNEYS Z2 W000 fizz/e 05 R0 55/? TL. [44m mpwmw Aug.'9, 1966 R. L. CRAIN ETAL WELL COMPLETION EQUIPMENT Filed Nov. 15. 1962 6 Shee fs-Sheet 4 F0557? r L.

ZZwaop KBEHCE ATTORNEYE Aug. 9, 1966 R. L. CRAIN ETAL 3,265,409

I WELL CQMPLETION EQUIPMENT Filed Nov. 15, 1962' v 6 Sheets-Sheet e 3 Q 0 33 r E INVENTORS ATTORNEYS United States Patent f poration of Texas Filed Nov. 15, 1962, Ser. No. 237,959 Claims. (Cl. 285-27) This invention has reference to a new and improved apparatus for completion of Wells and has particular reference to new and improved equipment for supporting the tubing string at the tubing head.

In the patents to Roy, Pat. No. 2,207,469; Smith, Pat. No. 2,148,327; and Mueller, Pat. No. 2,157,964, apparatus and procedures for setting the casing or tubing head are disclosed wherein relative movement between the string and the head is provided so that bends may be taken out of the string. In these prior art patents, the equipment is particularly suited for single strings, although it will be appreciated that the techniques and equipment for handling single strings are equally well suited for sup porting multiple tubing strings. A significant consideration, however, in suspending parallel strings in the well resides in utilizing to a maximum extent the available space within the tubing head so that as large a diameter tubing string as possible can be adequately handled. Moreover, it is desirable to allow a degree of longitudinal movement of the tubing hanger carrying the string relative to the hanger body prior to setting the hanger in order that bends and the like can be removed from the tubing string, as particularly disclosed in the patent to Smith, Pat. No. 2,148,327.

This invention contemplates the provision of new and improved apparatus and equipment for setting a tubing string in a tubing head wherein relative movement is obtained by the tubing hangers relative to the hanger body prior to setting the same. To this end, the tubing hanger is constructed and arranged to move freely through the associated passage in the hanger body and is constructed and arranged to carry a resilient sleeve collet which is adapted to be slipped longitudinally downwardly along the tubing hanger, without rotation, and engaged therewith so that when these elements are then lowered together, the tubing hanger is supported on the hanger body via this resilient collet. This procedure is adapted to take place through control equipment mounted on the tubing head and tools are provided for manipulating the resilient collet for movement into engagement in the tubing hanger, and for subsequent removal over the resilient collet sleeve when the equipment is to be disassembled. By virtue of this arrangement, the bends and the like in the tubing string will be elfectively removed due to the fact the tubing hanger can be moved through the hanger body and is subsequently supported in the tubing head, when the resilient collet is engaged therewith.

The instant application also contemplates such equipment in conjunction with multiple tubing strings suspended in the well. To this end, two resilient collets are provided for engagement with the tubing hangers, each of these collets being of arcuate configuration in plan, the open portions facing one another. At this region, the outer periphery of each collet is flat, there being provided a longitudinal shoulder at the arcuate extent of each collet, each collet thence merging with a tapered wall. Thus, when two collets are positioned adjacent one another with their fiat surfaces aligned, opposed recesses are formed by each of the aligned shoulders. These opposed recesses are adapted to receive a spreader tool which is adapted to spread out the radial configuration of both resilient collets so that they may be radially stressed and removed from their respective tubing hanger.

Patented August 9, 1966 By virtue of the tapered configuration of the collet adjacent these recesses, the tool is biased toward the recesses for convenience in manipulation through the control equipment. Also, in order to force the resilient collet downwardlyalong the hanger in its expanded position, another manipulating tool is provided of U-shaped configuration so as to surround the tubing hanger and snap the same into the peripheral recesses in each tubing hanger. In the preferred embodiment of this invention, the resilient collet has longitudinal slots extending from both ends, which slots overlap one another so that the structure may be resiliently expanded and contracted be tween a stressed and a relaxed condition. Thus, the collet is latched and unlatched from the tubing hanger solely with manipulation in a longitudinal direction, and avoids the difiiculty of manipulation as would be occasioned by a threaded connection between the collet and the tubing hanger.

Still further according to this invention, new and improved means for supporting the tubing hangers on the hanger body is provided. In this regard, the upwardly facing tapered seating surface around each passage in the hanger body is of a new configuration to allow maximum utilization of the space in the tubing head and the Well. The outer body of each seating surface may be defined by an arc (in a multiple hanger) which has its center at a point laterally oifset from the axis of its respective passage. By virtue of this arrangement, the tubing hanger, whether of conventional construction or of the type disclosed in this invention is more efliciently guided into its proper setting position than in cases where the sealing surface is simply defined by a-concentric circle having its center coincident with the axis of the passage. Further, a more generous seating area is provided so as to distribute the load in a more efficient manner. In another arrangement, the exterior diameter of each sealing surface in the multiple hanger body is such that it extends laterally beyond the opposite sides thereof, so that the major seating area is not at the opposed sides of the hanger body but rather in the central region.

These and still further objects, advantages and novel features of the present invention will become apparent in the specification and claims, taken in connection with the accompanying drawings.

In the drawings:

FIGURE -1 is a sectional elevation view of equipment for suspending multiple tubing strings in a Well according to one feature of this invention;

, FIGURE 2 is a sectional plan view taken along line 2-2 in FIGURE 1;

FIGURE 3 is a plan view of the resilient collets according to this invention;

FIGURE 4 is an elevation section view of the collets taken along line 4-4 in FIGURE 3;

FIGURE 5 is a perspective view of a lowering wrench operative in conjunction with the resilient collets and the tubing hangers;

FIGURE 6 is a perspective view of a spreader tool for use in removing the collet sleeves from the tubing hangers;

FIGURES 7-15 v are diagrammatic sequence drawings of the successive stages in completing the suspension of the tubing strings;

FIGURE 16 is a plan view of a modified hanger body construction;

FIGURE 17 is an elevation section view taken along line 17'17 in FIGURE 16;

FIGURE 18 is a plan view of another modified hanger body construction;

FIGURE 19 is an elevation sec-tion view taken along line 19-19 in FIGURE 18;

FIGURE 20 is .a longitudinal section view of another tubing hanger;

FIGURE 21 is a sectional view taken along line 2121 in FIGURE FIGURE 22 is a modification of the tubing hanger flange configuration in FIGURE 21;

FIGURE 23 is a plan view similar to FIGURE 2 showing modified resilient collets seated in the hanger body shown in FIGURES 16 and 17;

FIGURE 24 is another plan view similar to FIGURE 2 showing still different resilient collets seated in the hanger body shown in FIGURES 18 and 19;

FIGURE 25 is a plan view of collets similar to FIG- URE 3 but showing a modified construction; and

FIGURE 26 is a perspective view of a tool adapted to spread the collets in FIGURE 25.

Referring now to FIGURES 1, 2 and 7, there is shown a tubing head 30 mounted on a casing head (not shown) and having a longitudinal passage 31 and a tapered bowl 32 for supporting a tubing string as will be discussed. Also, the tubing head has the usual upper and

lower flanges

33, 34, respectively, and opposed side outlets 35. The tubing head carries opposed alignment screws 36 which are movable into and out of the passage 31 below the bowl 32. A parent hanger body 37 is adapted to be seated about its lower exterior surface in the tapered bowl 32, the hanger body 37 preferably being constructed in the manner generally as disclosed in the copending application of Watts et al., Serial No. 19,323, filed April 1, 1960, now Patent No. 3,118,690.

In this regard, the hanger body 37 has two

circular passages

38 and 40 with tapered

seats

42 and 44, respectively, surrounding the upper end of these respective passages. Likewise, the hanger body 37 has opposed depending peripheral skirts 46 along its sides and intermediate the

hanger body passages

38 and 40. The opposed arcuate skirts have longitudinally extending slots 48 therein, which are arranged to be engaged by the alignment screws 36 after the hanger body 37 is seated in the tubing head bowl 32. The top surface of the hanger body has opposed threshold holes 49 for use during landing operations.

Tubing hangers

50 and 52 are adapted to be supported within these

respective passages

38 and 40 via

resilient sleeve collets

54 and 56, respectively.

The

tubing hangers

50 and 52 are of identical construction and like reference numerals will be used to designate similar elements in the two tubing hangers. Accordingly, each tubing hanger is interiorly threaded at its tapered lower end 58 so as to receive the upper end of two

tubing strings

60, 62. Each hanger is of generally cylindrical construction about its exterior surface and has a peripheral recess 64 formed intermediate its upper and lower end so as to define upper and lower radial shoulders 66 and 68, respectively. The upper shoulder has a. downwardly facing taper 70 about its outer extremity for reasons to become evident. The upper end of each tubing hanger is also tapered and has an interiorly threaded portion with left-handed threads 72 to receive a lowering nipple 74 in the usual fashion. An interior longitudinal passage 76 in each of the tubing hangers is formed with a radially extending central shoulder portion 78 so as to receive a suitable pressure valve (not shown). Also, the upper tapered end of each tubing hanger carries an O-ring seal 80 made of hydraulic packing for subsequent sealing with a bonnet.

Each

tubing hanger

50, 52 has an exterior diameter which is substantially less than the interior diameter of the respective passages 38 and 40' in the hanger body 37. This allows each tubing hanger to be longitudinally movable with respect to the hanger body 116 (through the passages) for reasons to become apparent. In order to support the

tubing hangers

50 and 52 on the

seats

42 and 44 of the hanger body 37, the

resilient collets

54 and 56 are adapted tobe snapped into engagement within the peripheral recess 64 of each tubing hanger.

Referring now to FIGURES 3 and 4, the construction of the

collets

54 and 56 is shown in detail. The

collets

54 and 56 are of identical construction, being of arcuate configuration in plan with their open sides facing one another. The collets are generally of cylindrical construction and have radially spaced longitudinal slots and 82 extending from the upper and lower ends in overlapping relationship so that each collet is radially exp ansible when forcibly stressed. Suitable holes 84 are drilled or otherwise formed in the collets in the ends of each of the long slots, for purposes of structural rigidity. The collets have arcuate upper flanges 86 with an inclined lower surface 88 which are adapted to nest on the

tapered seats

42 and 44 of the hanger body 32. Conveniently, there is pro vided an undercut 90 at the lower end of eachof' these inclined surfaces 88 While the inside upper end of the flange 80 has an inclined shoulder 91 adapted to engage the shoulder tapes 74 of the tubing hanger. Each collet has a flat longitudinally extending surface 92 at the opposed arcuate extremities of the collet, these surfaces being angularly inclined along a radial line extending from the axis of each collet. Also, each collet flange 86 has aligned flat longitudinal surfaces 94 at each arcuate extent which are adapted to abut the adjacent fiat surfaces 94 of the adjacent collet flange when the

collets

54, 56 are seated on the hanger body 16 in arcuate-facing relationship. At the opposed arcuate extremities of each of the collet flanges 86 there is provided an outwardly facing longitudinal slot 96. Thus, when the

collets

54 and 56 are seated within the hanger body and abut one another, the slots 96 of one collet flange form with the adjacent slot of the other collet flange a longitudinal recess 98. The recesses 98 are opposed to one another and their purpose will become evident. The

collets

54 and 56 have a normal exterior diameter (when relaxed) below each upper arcuate flange 88 which is slightly less than the interior diameter of the

circular passages

38 and 40 so that the collets, like the

tubing hangers

50 and 52 are longitudinally movable into the

passages

38 and 40 except for their upper flanges 86.

The interior diameter of the collets54 and 56 at their upper end 100 is normally less than the maximum exterior diameter of each tubing hanger but slightly great: er than the interior diameter of each tubing hanger along the peripheral recess 64, when the collet is in a relaxed condition. The lower interior part 102, however, is greater than the maximum exterior diameter of the

tubing hangers

50 and 52, and an inclined shoulder 104 defines the intersection of each of the two

integral parts

100, 102 of the collets S4 and 56. The length of the upper interior part of the collet (from the top to the shoulder 104) is substantially less than the length of the peripheral recess 64 in each

tubing hanger

50, 52. Conveniently, the lowermost exterior part of the collet is tapered at 105 for ease of assembly.

Referring now to FIGURE 5 there is shown a manipulating Wrench 106 which is in the form of a U-shaped lower portion 108 having a slightly larger interior opening 110 than the maximum exterior diameter of the

tubing hangers

50 and 52, but nevertheless operative to engage the collet flange 86 of each

collet

50 and 52. The Wrench 106 has a long handle 112 joined to the outside base of the lower portion 108 as by Welding so that the wrench can be moved through control equipment on top of the tubing head 30.

Another manipulating tool 114 (FIGURE 6) is in the form of an interiorly threaded member 116 having a depending flat plate 118 welded to its lower end. The plate 118 has a bottom portion 120 of generally triangular con figuration and is of a width sufficient to be received in the longitudinal recesses 98 in the aligned

collets

54, 56. This arrangement is such that the plate 118 can extend down: wardly between the opposed recesses 98, forcing the collets to expand and thereby release each collet from its engagement in the peripheral recess 64 of the

respective tubing hangers

50 and 52. Such manipulation is acc0mplished by threading a long handle, e.g., a pipe (not shown) into the member 116.

Referenceis now made to FIGURES 7-15 which show the sequence of completing the well. In FIGURE 7, the

' tubing head 30 is mounted on the casing head (not shown) in the usual fashion, and the first tubing string 60 has been set. All logging, perforating, and wireline packer setting has been completed with the lower end of the first tubing string 60 being latched to the packer in the well. The tubing hanger 50 carries a back pressure valve (not shown) and blowout prevention equipment is installed in the usual fashion. The tubing hanger 50 is below the point of its final landed position, i.e., the bowl 32 in the tubing head 10. The tubing hanger 50 is supported in this position by the lowering nipple 74 which has been threaded into the upper interior threads in the tubing hanger 50. Bearing in mind that the tubing hanger 50 is freely movable longitudinally through the hanger body passage 38, the hanger body 37 is lowered down the tubing to the tubing head bowl 32 by means of a pipe 122 screwed into each hole 49 in the top of the hanger body 37. The hanger body 37 is thus maneuvered into its landed position so that the tubing head alignment screws 36 (previously withdrawn) can be threaded inwardly and thereby engage the slots 48 in the hanger body depending skirts 46. By this arrangement, the hanger body 37 cannot rotate after landing takes place, and cannot become inadvertently dislodged. The distance of the tubing hanger 50 below the tubing head bowl 32 corresponds to the amount of stretch or tension to be imparted to the tubing string 60 so as to remove the bends or the like as disclosed, e.g., (in the patent to Smith, No. 2,148,327.

Referring to FIGURE 8, the hanger body 37 has now been landed in seating engagement with the tubing head bowl 32. The first tubing string 60 is stretched via the nipple 74 so that the first tubing hanger 50 passes upwardly through the hanger body passage 38. The tubing hanger 56 is elevated a distance sufliciently above its final landed position relative to the hanger body 37 so as to allow the collet 54 to be snapped into engagement with the tubing hanger 50 as will now be explained. The collet 54 is lowered down past the lowering nipple 74 and the upper tapered end of the tubing hanger 50 in preparation for engagement with the peripheral recess 64 of the tubing hanger 50. To this end, the wrench 106 (FIGURE 6) is placed above the collet 54 and is manually forced downwardly so that its underside engages the top surface of the collet flange 86. As this manipulation occurs, the collet 54 is stressed radially outwardly due to the slotted construction of the collet (FIGURE 4) and the smaller interior diameter of the upper part 100 of the collet relative to the upper exterior diameter of the tubing hanger 50 above the peripheral recess 64. As downward force is exerted with the wrench 166, the collet 54 will snap into the peripheral tubing hanger recess 54 when the top surface of the collet 54 clears the upper shoulder 66 of the tubing hanger 50 adjacent the peripheral recess 64. The collet 54 is then in a relaxed state and its upper surface is in engagement with the tubing hanger upper shoulder 66. Thus, while tapered engaging surfaces 91 and 70 are here shown, it is evident that these tapers may be omitted as desired. A secure surface-to-surface engagement is provided at this region, the top surface of the collet con veniently bridging about one-half the entire radial distance of the upper shoulder 66, though the inclined part 70 occupies less than one-half the distance.

Moreover, the nipple 74 has raised the tubing hanger 50 sufliciently above the top surface of the hanger body 37 so that the exterior diameter of the collet 54 below the flange 86 is not obstructed by the hanger body during this initial seating operation. That is to say, the interior diameter of the passage 38 in the hanger body 37 will be smaller than the exterior diameter of this lower part of the collet 50 (below the flange 86) when in the expanded state but not when the collet 54 has been snapped into engagement with the tubing hanger recess 64, as described. A snug fit is provided in the latter situation between the collet 54 and the passage 38, and the lower tapered exterior part facilitates alignment.

In FIGURE 9, the tubing hanger 50 and its collet 54 have been lowered so that the bottom surface 83 of the collet flange 86 is seated onto the tapered surface 42 of the hanger body 37 except, of course, for the part of the collet 54 between the arcuate extents of the flange 88, this part of the collet 54 facing the second hanger body passage 40 in the hanger body 37. The left-handed exterior threads in the lowering nipple 74 are unscrewed from the tubing hanger 50 and the tubing hanger 50 with its tubing string 60 is thereby assembled in the tubing head 30 with the bends in the string removed.

In FIGURE 10 operations have commenced with the second tubing string 62. This second tubing string 62 is lowered in a like manner through the blowout preventers (not shown) and the second passage 40 in the hanger body 37 (FIGURE 1). The lowering nipple 74 is removed, the tubing string is slackened off and released from the packer. When the correct amount of tubing 62 to be used has been determined, the second tubing hanger 52 is threaded onto the tubing string and the string '62 is again lowered until latched with the packer. At this point (FIGURE 11) the hang-er 52 is below its final position, by an amount corresponding to the desired stretch or tension to be taken in the tubing string 62 as to remove bends and the like. The back pressure valve (not shown) has been inserted in hanger in the usual fashion.

A tension is then taken on the second string 62 in the same manner as previously described with respect to the first tubing string 60. The same procedure is repeated: the second collet 56 is forced downwardly and stressed about the upper part of the second tubing hanger 52 by the wrench 106. Further downward movement of the second collet allows the same to be snapped into engagement wit-h the tubing hanger 52 within the peripheral recess 64. Then, the collet 56 is positioned so that its flange surface 88 is seated onto the hanger body seat 44 with its arcuate extent facing the arcuate extent of the first collet 54. This a'rrangeemnt of the elements is best shown in FIGURE 1.

Prior to removing the lowering nipple 74 and the equipment associated therewith, a pack-off assembly 124 is placed over the lowering nipple 74 and forced into position around the

tubing hangers

50 and 52. This procedure is shown in FIGURE 13; and, the pack-01f assembly per se is of known construction such as disclosed in the copending application of Watts et al., 19,323, filed April 1, 1960. The tubing head set screws are moved inwardly for engagement with the packoff 124 within the tubing head 60 and the lowering nipple 74 is removed from the tubing hanger 52, FIGURE 14.

As shown in FIGURE 14, this operation has been completed and the blow-out preventers (not shown) have been removed. FIGURE 15 shows the subsequent step of well completion wherein a dual bonnet 126 has been bolted to the upper flange 33 of the tubing head 30, there being provided the usual sealing ring 128. between these adjacent surfaces. Suitable testing can then commence in order to detect leaks. Upon completion of the testing, back pressure valves (not shown) are removed and the operation is completed.

In order to disassemble the equipment and remove the

tubing hangers

50 and 52, the reverse procedure is followed. In this regard, the tubing hangers '50 and 52 are elevated above the hanger body 37 and the manipulating tool 114 is inserted between the opposed recesses 98 defined by the longitudinally facing collet shoulders 96 so as to expand the same out of engagement with the peripheral recess 64 in the tubing hangers. The Wrench 106 is then inserted about each tubing hanger below its collet to elevate the same above the peripheral recess 164 and allow the

tubing hangers

50 and 52 to be lowered below the hanger body 37 so that each tubing string ;60, 62 may be disengaged from the packer and the tubing string removed. Disengagement of the

collets

54, 56 from the

respective tubing hangers

50, 52 is facilitated by virtue of the inclined surfaces 70 and 91 therebetween.

Reference is now made to FIGURES 16-24 which show variations of the dual well-completion equipment shown in FIGURES 1-15.

FIGURES 16, 17, and FIGURES 18, 19, show variations 37a and 37b of the hanger body construction, like elements of these respective embodiments being referred to with the same numerals.

In FIGURES 16 and 17 the inclined seating surfaces 42a and 44a are non-concentric with respect to the axes A and A of their respective passages, 38a and 40a. The radius of each passage and the position of the axes A and A is such that the passages are tangent to one another along a line drawn between A and A there being a consequent absence of a seating surface at this region. Thus, passages 38a and 3812 are close together and spaced inwardly of the opposed side walls of the hanger body 37a. The respective centerpoints C and C of the inclined seating surfaces 42a and 44a, however, are non-concentric with respect to the axes A and A being spaced outwardly thereof along the line between A and A The radius of the outer boundary of the seating surfaces 42a and 44a is such that there is a lost area 132 on opposite sides of the hanger body 37a due to the fact this radius extends beyond the hanger body sides. This arrangement provides a generous seating surface at the outside region of the seating surfaces 42a and 44a, diminishing in both depth and area towards the central region of the hanger body 37a. By this arrangement, relatively large passages 38a and 40a are thereby provided with the major seating area adjacent the opposed sides of the hanger body 37a.

In FIGURE 18 the opposite relationship of the passage axes A A and the seating surface underpoints C C is provided. In this embodiment of the hanger body 371:, the centerpoints C C are disposed along the line between A and A towards one another in spaced apart relationship to these hanger body passage axes. The major seating area of the inclined seats 42b and 44b is thereby provided in the central region of the hanger body 37b. Moreover, the passages 38b and 40b are spaced apart from one another so as to provide a central ridge 136 similar to that shown for the concentric seating surfaces 42 and 44 in the embodiment of the invention in FIGURES 1-15. Also, positioned on the top surface of the hanger body 37b along a perpendicular line bisecting the line between A and A are opposed tapered guide pins 138 which bridge the outer extent of the seating surfaces 42b and 44b in this region. These guide pins 138 are threaded at their lower ends and received in cooperatively threaded passages at the upper surface in the hanger body 37b.

Significant advantages are obtained by the construction of the hanger bodies in FIGURES 16-20. The arrangement of the seating surfaces provides maximum access to the annulus of the casing (not shown) and the offset relationship of the seating surface provides for receiving the tubing hangers and angularly bringing them to the correct center line of operation when landed. Upon viewing FIGURES 17 and 19, it will be evident that the tubing hangers will be landed outwardly due to the configuration of the seating surface in FIGURE 17, while the tubing hangers will tend to land towards the center of the hanger body in FIGURE 19. With respect to the arrangement in FIGURE 19, the upright tapered pins 138 are adapted to align the tubing hangers and prevent their turning, and as will become evident, the supporting flange carried by the tubing hangers have a special configuration so as to cooperate with the upright pins 138 for this purpose.

Moreover, the passages in the hanger body are of more generous size in both instances due to the fact the major supporting area is in the region of the seating surface transverse to the line between A and A Landing of the tubing hanger isthereby facilitated to a considerable degree.

Reference is now made to FIGURES 20 and 21 which show one modified arrangement for hanging the parallel tubing strings in the hanger body. In these embodiments of the invention, the exterior configuration of the tubing hanger is very much like that described in the Watts et a1., Patent No. 3,001,803. In this patent, there is provided an integral exterior flange joined to the tubing hanger for 360 seating with the adjacent parent hanger body. The tubing hanger 140 in FIGURE 20 simply provides for milled flats along the opposite sides of an otherwise continuous flange 142 which is adapted to seat with its tapered seating surface 144 on the hanger body 37a. In FIGURE 21, the opposed milled flats 146 are shown parallel to one another.

The tubing hanger 140 in FIGURES 20 and 21 is thereby adapted to be landed with another identical hanger in the hanger body, shown in FIGURES 17 and 18 wherein the facing flats 146 are closely adjacent one another when two such tubing hangers are landed. It will be appreciated that the provision of the integral flange 142 on each tubing hanger 140 is such that a strain cannot be taken in the manner described in FIGURES 1-15 due to the fact the integral tubing hanger flange 142 cannot pass through either of the passages 38a and 40a. However, in instances where it is not necessary to take a strain on the tubing string, the arrangement of the integral flange 142 with the tubing hanger 140 may be fully satisfactory.

FIGURE 22 is a modification of the flange 142 in FIGURES 21 in that two opposed sets of milled flats 148 converge angularly towards one another so that when two such hangers are landed side-by-side in the hanger body shown in FIGURES 19 and 20, the guide pins 138 are arranged to align the tubing hangers into their landed position. Thus, while the FIGURE 21 flange arrangement provides for alignment by engagement of the outer periphery of the flange with the tubing head bowl, the arrangement in FIGURE 22 accomplishes similar alignment by engagement with the upright pins 138.

Reference is now made to FIGURES 23 and 24 which show the hanger bodies 37a and 37b cooperating with resilient collets 54a, 56a and 54b, 56b, respectively. These collets are generally similar in material respects to the collects 54 and 56, like numerals referring to the same elements.

Referring first to FIGURE 23, it will be noted that the collets have the milled flats 94a which abut one another when the collets are joined to their

respective tubing hangers

50 and 52 in the manner described with reference to FIGURES 1-1i5. However, their arcuate extents defined by inclined outwardly converging walls 150 are opposed to one another rather than facing one another as shown in FIGURES 2 and 3. Also, as shown in FIGURE 23, when these collets 54a and 56a are landed with their

respective ahangers

50 and 52 into the hanger body 37a, the configuration of the seating surfaces in elevation (FIGURE 17) is such to throw the

tubing hangers

50 and 52 away from one another toward the outside of the hanger body 370. The outside extent of each flange 86a defined by angularly milled flats 152 is such that each resilient collet is guided downwardly into its landed position both by the adjacent bowl surface of the tubing head and by the milled flats 94a which abut one another. Thus, when the

tubing hangers

50 and 52 are landed, they are non-concentric with the axis of the respective passages 38a and 40a and outwardly thereof. By this arrangement, efl'lcient landing is accomplished and maximum use is made of the hanger body area for receiving the largest size tubing hanger. When the elements are to be removed and the tubing head disassembled, it will be evident that one tubing hanger can be elevated above the other and an expander tool wedged into the space defined by the outwardly converging walls .150 so that each resilient collet can be removed from its tubing hanger.

In FIGURE 24, the opposite situation takes place in that the

tubing hangers

50 and 52 are drawn towards the center when landed due to the configuration of the seats 42b and 44b, as shown in FIGURE 19. In view of the fact the maximum extent of the seating surfaces 42b and 44b are defined by non-concentric circles (relative to their adjacent passages), as previously described, the resilient collets 54b and 56b have milled flats 148 along their outside extremities similar to that shown in FIG- URE 22. The inside extremities i.e., the longitudinal surfaces facing one another, have aligned angular walls 154 which cooperate with the upright pins 138 so that align ment is accomplished by virtue of these pins. In other respects, the arcuate extent of the configuration of the flanges when landed is the same as that shown in FIG- URES 2 and 3.

Reference is now made to FIGURE 25 wherein the

collets

54, 56 have aligned flats 94 which abut one another when assembled as described. However, the collet flanges 86 have opposed flat

longitudinal surfaces

156, 158 along their arcuate extents which intersect the flats 94. In this arrangement, the

surfaces

156, 158 are inclined opposite to that shown with respect to the surfaces 92 in FIGURE 3. That is to say, rather than constituting radial lines from the axis of the collets, there is a greater distance between the arcuate extents and the inner part of the collet than at the outer part and the surfaces thereby converge. Thus, when a spreading tool 160 is inserted (FIGURE 26) between the arcuate extents, the tool will have a tendency to be biased towards its

respective tubing hanger

50 or 52 rather than towards the slots 98 as shown in FIGURE 3. In this regard, the spreading tool includes a curved blade 162 of a generally T-shape so that the concave portion of the tool blade 162 is conveniently faced towards its respective tubing hanger to facilitate spreading action in the manner previously described,

From the foregoing description of the various embodiments of this invention, it is evident that the objects of this invention, together with many practical advantages are successfully achieved. While preferred embodiments of our invention have been described, numerous further modifications may be made without departing from the scope of this invention.

Therefore, it is to be understood that all matters herein set forth or shown in the accompanying drawings are to be interpreted in an illustrative and not in a limiting sense.

What is claimed is:

1. Well completion equipment for supporting parallel tubing strings in a tubing head or the like comprising: tubing hangers for each of the tubing strings to be supported, each of said tubing hangers including means at its lower end for engaging the upper end of a tubing string and means at its upper end for engaging lowering equipment, each of said tubing hangers including radially outwardly extending flange means, said flange means having downwardly and outwardly facing seating surfaces therein, a hanger body constructed and arranged for support within the tubing head, said hanger body having a plurality of circular passages in which said tubing hangers are disposed, said hanger body having an upwardly facing seating surface extending about each passage, each of said upwardly facing seating surfaces having a centerpoint which is non-concentric with respect to the axis of each of said hanger body passages.

2. Well completion equipment defined in claim 1 wherein said hanger body has two diametrically opposed passages, the upwardly facing seating surface for each passage being inclined and bounded at its outer extremity by an are having its center offset from the axis of its associated passage towards the other passage.

3. Well completion equipment defined in claim 1 wherein said hanger body has two diametrically opposed passages with longitudinal axes, the upwardly facing seating surface for each passage being inclined and bounded at its outer extremity by an arc having its center offset from the axis of its associated passage away from the other passage.

4. Well completion equipment defined in claim 2 including alignment means upon said hangers and tapered guide pins extending upwardly from said hanger body, said pins converging upwardly and being so constructed and arranged as to cooperate with said alignment means to arcuately align the tubing hangers as the latter are received in said hanger body passages.

5. Well completion equipment defined in claim 4 wherein said guide pins are positioned in opposed relationship on a line perpendicular to and bisecting a line between the axes of saidv passages, said flange means being constructed and arranged to guidingly receive said pins therebetween.

6. Well completion equipment comprising: a hanger body having means defining a plurality of longitudinally extending, arcuately spaced passages therethrough and constructed and arranged to be landed in a tubing head,

said hanger body having upwardly facing inclined seats,

about the upper end of each of said passages; a plurality of tubing hangers each having a maximum size suflicient to pass upwardly through a passage in said hanger body, each tubing hanger having a longitudinally extending peripheral recess intermediate its upper and lower ends defining thereby a downwardly facing supporting shoulder; and a unitary resilient collet for each tubing hanger, each collect having means thereon which permit the collet to be radially expanded and moved down its respective tubing hanger in a stressed, radially expanded condition and thence contract within the peripheral recess so that the upper end of the collet engages said downwardly facing supporting shoulder, the interior diameter of each collet at the near end thereof being greater than the exterior diameter of each tubing hanger at the supporting shoulder thereof when each collet is in said radially expanded condition, and being less than the exterior diameter of each tubing hanger at the supporting shoulder thereof when each collet is contracted, each of said collets having a flange which seats upon the upwardly facing seat of the hanger body, whereby said tubing hanger can pass upwardly through its passage to take a strain on a tubing string attached to its lower end and the collet can then be moved into engagement with the tubing hanger, and the assembly can he landed on the hanger body; said tubing hanger being supported by said collets and said collets being supported by said hanger body; each collet being of arcuate configuration with an arcuate extent of more than degrees but less than 360 degrees wherein the arcuate extremities of said collet define a longitudinal opening extending the axial length of said collet, said collets being constructed and arranged to support said tubing hangers with the longitudinal openings in facing relationship.

7. Well completion equipment defined in claim 6 wherein a portion of the longitudinal opening in each collet is defined by radially outwardly diverging longitudinal walls in said flange which face one another, each of said walls having longitudinal slots at their outer extremities to thereby define opposed recesses when the adjacent collets are landed on said hanger body.

8. Well completion equipment comprising: a hanger body having means defining a plurality of longitudinally extending, arcuately spaced passages therethrough and constructed and arranged to be landed in a tubing head, said hanger body having upwardly facing inclined seats about the upper end of each of said passages; a plurality of tubing hangers each having a maximum size suflicient to pass upwardly through a passage in said hanger body, each tubing hanger having a longitudinally extending peripheral recess intermediate its upper and lower ends defining thereby a downwardly facing supporting shoulder; and a unitary resilient collet for each tubing hanger, each collet having means thereon which permit the collet to be radially expanded and moved down its respective tubing hanger in a stressed, radially expanded condition and thence contract within the peripheral recess so that the upper end of the collet engages said downwardly facing supporting shoulder, the interior diameter of each collet at the near end thereof being greater than the exterior diameter of each tubing hanger at the supporting shoulder thereof when each collet is in said radially expanded condition, and being less than the exterior diameter of each tubing hanger at the supporting shoulder thereof when each collet is contracted, each of said collets having a flange which seats upon the upwardly facing seat of the hanger body, whereby said tubing hanger can pass upwardly through its passage to take a strain on a tubing string attached to its lower end and the collet can then be moved into engagement with the tubing hanger, and the assembly can be landed on the hanger body; said tubing hanger being supported by said collets and said collets being supported by said hanger body; each collet being of arcuate configuration with an arcuate extent of more than 180 degrees but less than 360 degrees wherein the arcuate extremities of said collet define a longitudinal opening extending the axial length of said collet, the upper interior diameter of each collet being substantially less than the lower interior diameter of each collet to thereby define an intermediate shoulder on each collet, the distance between the upper end of each collet and each respective intermediate shoulder being less than the longitudinal length of the peripheral recess in the respective tubing hanger, said flange on each collet being located adjacent the upper end of each collet the portion of each collet depending from each respective flange defining thereby a skirt on each collet, each skirt being of sufficiently small exterior diameter to pass through its associated passage in the hanger body, and said lower interior diameter of each collet at each respective skirt being larger than the exterior diameter of each respective tubing hanger adjacent thereto whereby slight allowance for longitudinal tilting of the tubing hangers relative to the respective collets is provided.

9. Well completion equipment comprising: a hanger body having means defining a plurality of longitudinally extending, arcuately spaced passages therethrough and constructed and arranged to be landed in a tubing head, said hanger body having upwardly facing inclined seats about the upper end of each of said passages; a plurality of tubing hangers each having a maximum size sufficient to pass upwardly through a passage in said hanger body,

each tubing hanger having a longitudinally extending peripheral recess intermediate its upper and lower ends defining thereby a downwardly facing supporting shoulder; and a unitary resilient collet for each tubing hanger, each collet having means thereon which permit the collet to be radially expanded and moved down its respective tubing hanger in a stressed, radially expanded condition and thence contact within the peripheral recess so that the upper end of the collet engages said downwardly fac ing supporting shoulder, the interior diameter of each collet at the near end thereof being greater than the exterior diameter of each tubing hanger at the supporting shoulder thereof when each collet is in said radially expanded condition, and being less than the exterior diameter of each tubing hanger at the supporting shoulder thereof when each collet is contracted, each of said collets having a flange which seats upon the upwardly facing seat of the hanger body, whereby said tubing hanger can pass upwardly through its passage to take a strain on a tubing string attached to its lower end and the collet can then be moved into engagement with the tubing hanger, and the assembly can be landed on the hanger body; said tubing hanger being supported by said collets and said collets being supported by said hanger body; said hanger body seating surfaces being tapered, the extent of said tape-red seating surfaces being bound by arcs having center points which are non-concentric with respect to the axis of the associated passage.

10. Well completion equipment defined in claim 6 wherein a portion of said longitudinal opening of each collet is defined by radially outwardly converging longitudinal walls in said flange.

References Cited by the Examiner UNITED STATES PATENTS 2,010,284 8/1935 Wickershan 285141 2,122,071 6/ 1938 Rasmussen 285141 2,189,575 2/1940 Brown 2,85143 2,312,476 3/ 1943 Penick 166-89 3,011,552 12/1961 Rhodes 285137 3,020,069 2/ 1962 Word 285--137 3,071,193 1/1963 Raulins 285321 3,071,396 1/ 1963 Neilon 285-137 3,097,000 7/1963 McClintock 285-321 CARL W. TOMLIN, Primary Examiner.

S. R. MILLER, D. W. AROLA, Assistant Examiners.