US3438654A

US3438654A - Well completion apparatus

Info

Publication number: US3438654A
Application number: US364843A
Authority: US
Inventors: John G Jackson Jr
Original assignee: Rockwell Manufacturing Co
Current assignee: Rockwell Manufacturing Co; Smith International Inc
Priority date: 1964-05-04
Filing date: 1964-05-04
Publication date: 1969-04-15
Anticipated expiration: 1986-04-15

Description

April 1969 I J. G. JACKSON, JR, ET AL 3,438,654

WELL COMPLETION APPARATUS Filed May 4, 1964 Sheet of4 /06 ma 35 :4 4o 49' //2 //s 33 32 as 39 INVENTORS JOHN G. JACKSON, JR.,DECEASED BANK OF THE SOUTHWEST 2A 7/ 70 BY NATIONAL ASSOCIATION,HOUSTON,

, EXECUTOR JOHN BESON CHARLES R. CRAWFORD ATTORNEY A ril 15, 1969 J.IG.JACKSON,-JR., 1, 3,438,654

I WELL COMPLETI-ON APPARATUS Filed May 4, 1964 Sheet 3 of 4 INVENTORS JOHN G. JACKSON,JR.,DECEASED BY BANK OF THE SOUTHWEST NATIONAL ASSOCIATION, HOUSTON,

EXECUTOR JOHN BESON A13 CHARLES R. CRAWFORD ATTORNEY April 15, 1969 J 5, cKso ET AL 3,438,654

WELL COMPLETION APPARATUS Filed May 4. 1964 Sheet 3 of 4 INVENTORS JOHN G. JACKSON,VJR.,DECEASED BY BANK OF THE SOUTHWEST NATIONAL ASSOCIATION, HUSTON.

EXECUTOR JOHN BESON 2/0 CHARLES R. CRAWFORD AfI'OlF/VE V April 15, 1969 J. shJAcKsoN, JR, ET AL 3,438,654

WELL COMPLETION APPARATUS 'Filed May 4. 1964 Sheet 4 of 4 R as w m R Jl/ INVENTORS JOHN G. JACK$QN,JR,DECEASED BANK OF THE SOUTHWEST NATIONAL ASSOCIATION,HOUSTON,

EXECUTOR JOHN BESON CHARLES R. CRAWFORD Arrow/tr United States Patent Office 3,438,654 Patented Apr. 15, 1969 3,438,654 WELL COMPLETION APPARATUS John G. Jackson, Jr., deceased, late of Angleton, Tex.,

by Bank of the Southwest National Association, Houston, Tex., executor, John Beson and Charles R. Crawford, Houston, Tex., assignors to Rockwell Manufacturing Company, Houston, Tex., a corporation of Pennsylvania Filed May 4, 1964, Ser. No. 364,843 Int. Cl. F16c 21/00; T21b 19/10 U.S. Cl. 285-141 2 Claims This invention pertains to wellhead equipment for use in completion of wells. In the equipment, the usual casing and tubing hanger are combined. Through utilization of the equipment, completions of wells may be made 'apidly, without necessity for changing blowout preventers between installation of the casing head and installation of the tubing head or heads as the case may be.

A principal object of the invention is to provide speed head and hanger equipment for installation at the earths surface at the top of a well, The equipment provides combined casing and tubing heads, including hanger equipment therein for both casings and tubings, whereby the time required for completion of a well is reduced.

Another object of the invention is to provide well completion equipment wherein the casing and tubing hangers are installed within a single wellhead, so that the removal, changing and reconnection of blowout prevention equipment is not required during completion of a well.

Normally, in well completions, the several casings are each suspended from hanger equipment disposed in a separate casing head provided for support of each casing. Similarly, the tubing or tubings are supported normally in a separate tubing head. The surface or conductor casing usually is first run and cemented in the well bore, and the lowermost casing head mounted at its upper end. Then, drilling is continued and an additional casing head is installed, with blowout preventer removal, as each additional casing is run and set. Then, after all casings are in place, a similar procedure is followed for the tubing head and tubing strings. Thus, for a well requiring three strings of casing, it is usually necessary to remove and reinstall blowout prevention equipment three times before the well is finally completed, once for each casing string after the initial surface or conductor casing, and again for the tubing string or strings. Normally, also, different sizes and types of blowout prevention equipment will be required since the upper wellhead elements are invariably of smaller size than are the lower wellhead elements. This procedure is expensive and time consuming. It is also somewhat unsafe, since the well is at times unprotected by blowout preventers.

The single head member provided according to this invention is also mounted at the upper end of the surface or conductor casing in the well. But instead of placing a series of surmountingly connected wellheads above the lowermost wellhead, the single wellhead hereby provided provides head equipment to replace all of the previously used wellheads, The well remains protected by blowout preventers continuously during the entire assembly procedure, and only one blowout prevention assembly is required. Much time is saved because there is no necessity for changing the blowout preventers or for installing additional wellheads, with resultant economy and efficiency.

Also in accordance with the invention, novel hanger equipment is provided which is novelly supported within the wellhead without the necessity for any shoulder around the interior of the wellhead. In this way, the wellhead is made to have a substantially straight through bore without substantial hindrance of passage of any equipment therethrough during the drilling and completion of the well.

Other objects and advantages of the invention will appear from the following detailed description thereof, including presentation of two preferred forms of the apparatus according to the invention, reference being made to the accompanying drawings, of which:

FIG. 1 is a side elevational view of one preferred form of apparatus;

FIGS. 2A and 2B are vertical half sectional views showing the lower and upper portions, respectively, in enlarged showing, of the apparatus of FIG. 1 of the drawings;

FIG. 3 is a plan view, partly in horizontal cross section, of a portion of the apparatus shown in FIG. 2B, the showing being further enlarged;

FIG. 4 is a plan view, partly in horizontal cross section, of another portion of the apparatus shown in FIG. 2B; and

FIG. 5 is a side elevational view, partly in vertical cross section through the axis of the apparatus, showing a second preferred form of apparatus according to the invention.

Referring now first to FIGS. 1, 2A, and 2B of the drawings, the wellhead is screwed at lower interior threads 11 to the threaded upper end of surface of conductor casing 12 which extends downwardly into the well bore and which is usually cemented in place so as to form a foundation for the well equipment. Wellhead 10 has a vertical generally cylindrical passage 15 therethrough which is smooth-walled at its upper portions, and which near its lower end has a vertically spaced pair of upwardly facing conical seats or

shoulders

17, 18 therearound to support the lowermost of the several casing hangers which are mounted within Wellhead 10. The lowermost casing hanger is supported on shoulders for safety reasons, in order that there will be no possibility that the hanger equipment may be accidentally dropped down the interior of casing 12 which would cause need, possibly, of expensive and difficult fishing operations for its removal.

Wellhead 10 has a pair of oppositely positioned lateral outlets 19, only one being shown in the drawings, which are identical, and which consist of smooth bored passageways 20 each enlarged at their inner ends. A bolting flange 22 is provided at the outer end of each lateral outlet 19 for connection of other equipment, such as a valve, pipeline, choke, or the like.

Above annular seat 17 wellhead 10 has through its side wall a pair of oppositely disposed] tapped ports 24, only one being shown, each closed by a threaded plug screwed into the threads thereof and each of which has therein a ball check valve 26.

The ports 24 are used as test ports: to indicate leakage at the seals above and below the test ports, the plug 25 being removed for this purpose.

Vertically spaced above the ports 24 there are provided through the side wall of wellhead 10 a pair of oppositely positioned lateral outlets 28, only one being shown in FIG. 2A. Outlet 28, which is directly above outlet 19 as shown in FIG. 1, is shown out of position in FIG. 2A and thereby is indicated by dashed lines. The lateral outlets 28 are of the same form as the lateral outlets 19 and require no further description.

Spaced slightly above lateral outlets 28' of wellhead I10 there are provided a plurality of lockscrews 32. The true azimuthal positions of the lockscrews 32 around body 10 are indicated in FIG. 1, and the single lockscrew 32 shown in FIG. 2A is shown out of position for clarity. The lockscrews are circularly arranged about wellhead 10, each being threaded into a tapped opening 3-3 and each having therearound packing rings 34 disposed between packing support ring 35 and packing compression ring 36. A packing gland 39 is screwed into threads 40 at the outer end of the lockscrew housing 41, which is of integral tubular form and extends laterally outwardly from body 10.

Each lockscrew has a shaped outer end 44 for engagement by a wrench, or the like. A cover 42 encloses the outer end of each lockscrew 32. The covers 42 each slidingly fit over the outer end portion of a packing gland 39.

Spaced above the lockscrews 32, body 10 has another pair of ports oppositely disposed through its wall, these being designated by reference numeral 51, only one being shown. Each of these ports 51 is closed by a threaded plug 25 and each of the ports 51 has therein a ball check valve 26. These elements are the same as those of ports 24, and for the same purpose.

Spaced above the ports 51 of body 10 there is provided another set of lateral outlets 53, there being two of these oppositely disposed on body 10, only one being shown in FIG. 2B. The outlets 53 are identical with the previously described outlets 2-8 and 19. Their true azimuthal positions are shown in FIG. 1, above

outlets

28 and 19.

Above outlets 53 there is another plurality of circularly spaced lockscrews 55. These lockscrews 55 are mounted in tubular projections 56 which are identical with tubular projections 41, already described. The apparatus as shown in the drawings has six each of the lockscrews 32 and 55. The threads into which the lockscrews are received, the packing, packing retainer, packing support, and gland are the same as for the lockscrews 32. Each lockscrew is covered by one of the covers 42. The lockscrews 55 are shown out of position in FIG. 2B, their true positions being indicated in FIG. 1.

As is best seen in FIG. 2B of the drawings, each cover 42 has a side port 58 which is tapped to receive a set screw 59 to hold the cover in place, and a tapped port 60 into which is screwed a grease retainer 61, each of the covers 42 being filled with grease in order that the outer ends of the lockscrews will be protected against corrosion and other damage.

Above the lockscrews 55 in tubular projections 56, body 10 terminates upwardly in connection flange 60. Flange 60 has a plurality of bolt holes 61 therearound, indicated by dashed lines in the drawing. A plurality of lockscrews 64, equally spaced about flange 60, are provided radially through the flange. A steel ring gasket is disposed in suitable facing circular grooves in the upper surface of flange 60 and in the lower surface of a flange 67 of an additional piece of wellhead equipment which surmounts body 10, and which may be of any suitable or desired form, such as a blowout preventer, valve, or the like.

Still referring to FIGS. 1, 2A and 2B of the drawings, additional well casings 70 and 7 1 are concentrically positioned within casing 12. Within casing 71 there are disposed two parallel tubing strings 73, 74. The outer casings usually extend to a shallower depth within the well than do the inner casings. Casing 71, therefore, will be longer than casing 70 which in turn will be longer than casing 12. The tubing strings 73, 74 will normally extend about as deep as the casing 71.

Casing 70 is supported by a casing hanger 76. Casing hanger 76 is of the type described in United States Letters Patent No. 2,887,754, issued May 26, 1959, and in United States Letters Patent No. 2,824,757, issued Feb. 25, 1958. The packotf portion of the hanger, however, is of modified form. Hanger body 77 has vertical outer surface 78 in contact with the inner surface of wellhead 10 defining passageway 15. The hanger has conical seat or shoulder 79 therearound which corresponds in form with seat 18 and is seated on seat 18 when the hanger is fully loaded. As described in said Letters Patent No. 2,824,757, shoulder 79 will be above the seat 18 except with full load on the hanger. Slip segments 80, only one being shown,

are engaged upon conically tapered surface 81. The slips have inwardly facing teeth 82 and outwardly facing teeth 83. Inwardly depending flange 84 of the hanger body has tapped openings 85. A threaded screw 86 extends downwardly through the packotf and is screwed into tapped opening 85. The inner faces of slips engage casing 70 to support the casing. The lower end of hanger body 77 overlaps but does not colse outlets 19 so that outlets 19 provide access to the annular space within casing .12. The hanger is of the diametrically split wrap around type shown in the aforementioned Letters Patents. The packoff above hanger 76 includes lower packoff support ring 88, which has a shoulder of conical form therearound supported on shoulder 17. An elastomeric ring shaped sealing element 89 has lower inner flange 90, lower outer flange 91, upper inner flange 92, and upper outer flange 93, these flange portions of the sealing element being disposed in corresponding recess of the upwardly and downwardly adjacent steel rings, to provide increased contact at the points of seal together with amplified sealing contact because of the configuration of the sealing elements.

Above sealing element 89 there is a steel seal compression ring 97 formed upwardly and downwardly to receive the sealing material layer flanges, and around the interior surface of which there is provided an annular circular groove 98, and around the exterior thereof there is provided an annular circular groove 99. A plurality of circularly spaced radial ports 100 connect these two grooves. Only one port 100 is shown in the drawing. The groove 99 overlaps test ports 24.

Above ring 97 there is a second ring 102 of elastomeric sealing material, this ring being the same as ring 89. Above ring 102 there is a steel packing compression ring 103, which is urged downwardly against the other parts of the sealing assembly to compress rings 89 and 1102 to provide the described seals. The heads of the plurality of screws 86 are received in counterbores 10 4 at the upper surface of ring 103. The sealing elements described are all perforated so that the screws 86 are passed downwardly through all of these elements and screwed into tapped opening 85 of hanger body 77. As is described in United States Letters Patent No. 2,824,757 mentioned hereinabove, the seal is compressed by load imposed on hanger body 77 through slips 80, the seal compression being limited by the position of seat 18 with respect to shoulder 79 of hanger body 77. The seal assembly is also of the wrap around type.

While slip type casing hangers are shown in describing the preferred embodiments of the invention, other forms of easing hangers, supported in the described manners in the wellhead, may be substituted for one or both of the casing hangers shown and described. Similarly, other forms of tubing hanger equipment may be substituted for the tubing hanger hereinafter described, and supported in the described manner in the wellhead.

A diagonally split ring member 106 has outwardly directed flange member 107, the outer end of which contacts wellhead 10, the lower surface of which rests upon the upper surface of ring 103. At its upper surface, ring 106 has upwardly facing conical bevel 108 engaged by the lockscrews 32, which may thereby be used to compress

seal rings

89, 102. Around the outer surface of ring 106, there is provided encircling recess 110 which overlaps the lateral outlets 28 of wellhead 10. A plurality of circularly spaced ports 111, only one being shown in the drawings, are provided through ring member 106. The ports 111 and the end junctures of the split ring provide fluid flow communication between the interior of casing 70 and the lateral outlets 28. No azimuthal orientational alignment of the hanger ring 106 is required because encircling recess 110 provides the necessary communication regardless of the position of orientation of ring 106 in the wellhead. The lockscrews 32 also provide holddown means for ring 106 and the hanger 76 therebelow.

The inner surface 112 of ring 106 is spaced from the outer surface of casing 71. The inner surface 113 of ring 106 is closely space-d from the outer surface of casing 70. Upwardly diverging conical surface 115 of ring 106 provides a guiding surface for tools, and the like, introduced at a time when the interior casing 71 and the tubing strings have not yet been set.

A hanger 120 is provided above hanger 76 within the interior of wellhead for support of casing 71. Hanger 120 is not supported on a shoulder type of seat provided in wellhead 10. A diametrically split hanger support ring 121 has an outer surface fitted against the interior of wellhead 10 and has a downwardly and inwardly inclined flange portion 1210 providing an upwardly facing conical shoulder 123. Above member 121 there is provided a diametrically split hanger sleeve member 122 having at its lower end portion an upwardly facing conical seat surface 124. A hanger body 125 of wrap around form is seated upon seat 124 at a corresponding annular outer surrounding seat surface of the hanger body. Below this seat of the hanger body, the hanger body is inwardly relieved at its outer surface at 126, the relieved space being divided by a plurality of integral circularly evenly spaced vertical webs 127. The lower surfaces of the web members 127 are tapered as at 128. Above the shoulder of hanger body 125 which is seated on shoulder 124, the hanger body is inwardly relieved at its outer surface at 130, this relieved portion of the hanger body being divided by a plurality of integral circularly equally spaced webs 131. The web members 131 are outwardly relieved away from sleeve 122 at 132. Upper flange portion 134 extends outwardly above the relieved portions 130 and inwardly to almost contact casing 71 at inner surfaces 135. A plurality of circularly adjacent slip segments 136 engage tapered surface 137 of hanger body 125. The inner toothed surfaces 139 of the slips engage the outer surface of casing 71 to support the casing in the well, and the outer toothed surfaces 141 of the slips are engaged with surface 137.

Ring 121 is supported at its lower tapered surface 143 by the lockscrews 32. Sleeve 122 is supported by ring 121. Hanger body 125, therefore, is supported by ring 121 and sleeve 122. At its upper end, sleeve 122 has conical seat surface 146. A packoff assembly 148 rests at an outer annular conical shoulder upon seat 146 of sleeve 122. The packoff assembly 148 is the same as the packoif assembly above hanger body 77, except that assembly 148 has increased radial span, and parts thereof are denoted by the same reference numerals as the other packotf assembly with the suffix [I added to each reference numeral. Groove 99a is in register with test ports 51, previously described. A plurality of equally circularly spaced screws 86a have their heads disposed in a plurality of counterbores 104a in the upper surface of packoff compression ring 103a and these screws 86a extend through aligned perforations of the packotf elements to be screwed into tapped openings 85a equally circularly spaced around flange 134. The seal 148 has lower packoff support plate 882a, sealing ring 89a, intermediate ring 97a, upper sealing ring 102a and upper compression plate 103a.

The two hanger packoff assemblies which have been described are of the same type. The lower hanger and packolf which supports and seals around casing 70 is supported on

seats

17, 18. The upper hanger and packoff which supports and seals around casing 71 is supported on

seats

124, 146 of sleeve 122. The upper hanger and seal has larger radial span than the lower hanger since casing 71 is smaller than casing 70.

Diametrically split hold-down ring 196, which is likering 106 except having greater radial span, has lower flange portion 107a which bears on the upper surface of ring103a to holddown the hanger and the casing supported thereby, and has therethrough plural radial ports 111a. The upper beveled surface 115a serves to guide equipment introduced through the ring into the Well. Outer conical bevel 108a is engaged by the inner ends of 6 lockscrews 55 which urge ring 106a downwardly against the packoff.

Supported upon the lockscrews 55 is an annular ring having lower outwardly facing conical bevel 161 which is engaged by the lockscrews 55. Supported upon ring 160 are a plurality of circularly arranged slip segments 163. The slip segments 163 are inverted, the thinner ends of the slip segments being positioned upwardly with the thicker portions downwardly disposed. On their outer surfaces, the slips 163 are provided with downwardly directed teeth 164 which bite into the side wall of opening 15 of wellhead 10 and thereby support a substantial part of the weight of the pipe hanger supported by the slips. The inwardly facing surfaces of the slips 165 are tapered, downwardly converging, and a hanger body 167 having outer conical surface 168 corresponding to surface 165 is supported therein. Only one of the slips 163 is shown in FIG. 2B, the number of slip segments being selected for convenience of assembly. Usually three or four slip segments will be provided. Hanger body 167 has a plurality, two being shown, of openings 169 vertically and non-concentrically therethrough. The apparatus shown in FIGS. 1, 2A, 2B is for a dual completion well, and therefore two openings 169 are provided in hanger body 167. The number of completions may be as selected, more or less openings 169 being correspondingly provided in body 167.

Spaced from its upper end, each opening 169 has therearound an upwardly facing conical shoulder 171. A hanger mandrel is supported in each opening 169, each hanger mandrel 175 having therearound a downwardly facing shoulder 176 corresponding in form to shoulder 171. The

tubings

73, 74 are each screwed into lower threaded socket 177 of one of the hanger mandrels 175, and a pipe nipple 178 is screwed into upper socket formation 179. The pipe nipples 178 are provided for continuing flow through the tubings to equipment above the upper end of the tubings, and may be of any suitable form for connection with the upper equipment 67. The form of nipples 178, therefore, will be variable depending upon the remainder of the installation. As shown in the drawings, the nipples 178 are short nipples, threaded at their lower ends and not threaded at their upper ends, and are received through a packoff 182. The packoff 182 includes lower support plate 183, intermediate layer 184 of elastomeric sealing material, and upper compression plate 185. The lower outer portion of plate 183 is relieved at 186 to provide space for the upper ends of the slips 163. The upper outer surface of plate is conically bevelled at 187 for engagement by lockscrews 64. The

packoff elements

183, 184, have perforations therethrough to receive and seal around the pipe nipples 178.

Still referring to FIG. 2B of the drawings, the outer surfaces of split ring 121 and/ or of split sleeve 122 which engage the wall of passageway 15 may be provided with teeth or other surface aberrations to increase friction of their contact with the wall in exactly the same manner as the outer surfaces of slip segments 163. In this way, the load on lockscrews 32 may be materially reduced, if desired.

The described well completion apparatus afforded by this invention, as has been previously mentioned, provides a slngle wellhead which takes the place of the previously used plurality of Wellheads. Instead of a casing head and a tubing head, or a plurality of casing heads and tubing heads, one single head element serves the functions of all of these, without any detriment as regards safety and convenience of installation. All of the elements of the apparatus which are assembled within wellhead 10 will pass through blowout prevention equipment attached to surmount the wellhead 10. Therefore, the wellhead 10 may be put in place at the upper end of a well prior to completion of drilling, and then the well may be completed without any necessity for removing the blowout prevention equipment when drilling is completed. Normally, the blowout prevention equipment would have to be removed and either reinstalled or another form of blowout preven- 7 tion equipment substituted at the time each well pipe and additional wellhead is assembled.

Referring now to FIG. 3 of the drawings, there is shown a plan view, partially in horizontal section, of the slips 136 also shown in FIG. 2B. Four slip segments are shown in FIG. 3. Each slip segment 136 has spaced from its upper end a circumferential groove 195. The grooves 195 of the four slip segments are aligned to form a continuous groove around the entire set of slips. An arcuate bar 197 spans the space 198 between each pair of adjacent slip segments. The bars 197 are welded atone end at 199, the other end 201 of each bar 197 being slidingly received in the end of the groove 195 of the adjacent slip segment. Each slip segment has the inner and outer toothed formations, previously described.

Referring now to FIG. 4 of the drawings, there is shown a plan view, partially in vertical section, of the hanger body 125. In FIG. 4, there are shown, by dashed lines, the plurality of screws 203, each of which is screwed into a tapped opening in the outer face of each rib formation 127, each of these screws being disposed through a vertical slot 204 through ring 121. Similarly, and referring to FIG. 2B again, the plurality of screws 206 screwed into tapped openings spaced around the outer side of the central web of hanger 125, are each disposed through a vertical slot 207 through sleeve 122. The screws 203 retain hanger 125 and split ring 121 in assembled condition during installation, and the screws 206 similarly hold split sleeve 122 assembled with the hanger. The hanger is free to move axially of wellhead 10 when the sleeve and ring have been set in place upon the lockscrews 32. The inwardly facing surface 135 of hanger 125 has relieved portions 135a to decrease the weight and cost of the hanger.

As is shown in FIG. 4 the hanger 125 is made in two half-sections, the two halves together forming the ring shape of the hanger. A pair of oppositely disposed pin members 210 are received in facing perforations of the hanger halves in order that the hanger halves will remain in aligned positions one to the other.

Ring 121 and sleeve 122 are also supplied in half ring form in order that they may be assembled about a casing extending up through wellhand 10. The locations of the cuts of the rings, sleeve, and hanger may be staggered in order that a unitary assembly may be formed when the ring and sleeve are screwed onto the hanger body. The elements of

packofis

148 and 182 are similarly split in order that assembly may be readily accomplished, as shown in the aforementioned Letters Patents.

Referring now to FIG. 5 of the drawings, there is shown another preferred embodiment of the invention. The apparatus shown in FIG. 5 is similar to that of the other drawing figures. However, since the well with which the FIG. 5 embodiment of apparatus will be used requires a lesser number of casings, the equipment is simplified by omission of the casing hanger located second from the bottom in FIGS. 2A and 2B, the corresponding intermediate part of the wellhead also being absent. The wellhead 310 is the same as wellhead 10, except that the portion of wellhead between sets of lock-screws 32, 55 is omitted, and the hanger and packoff disposed therein and casing 71 are also omitted. The single set of lock-screws 332 of FIG. 5 correspond in part to each of the sets of lockscrews 32, 55 of FIGS. 1, 2A, 2B. All other parts of wellhead 310 are referred to in FIG. 5 by the same reference numerals as are used in the other drawings, plus 300. For example, seat 18 of FIG. 2A is referred to as seat 318 in FIG. 5. The hangers, packoffs, tubings and casings shown in FIG. 5 are referred to by the same reference numerals used in the other drawings, and the same descriptions thereof as have been made apply equally suitably to the apparatus of FIG. 5.

According to the teachings herein presented, well-heads for any desired number of casing and tubing strings may be readily provided.

While preferred embodiments of the invention have been shown and described, 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. Apparatus comprising:

a wellhead body having a substantially cylindrical vertical bore therethrough and a wall around said bore,

pipe hanger means positioned within said bore,

means on said pipe hanger means to support a well pipe therebelow,

seal means above and supported by said pipe hanger means positioned to sealingly engage said vertical bore and a tubular member extending upwardly from said well pipe, upon being vertically compressed,

means on said body engageable with said seal means to compress it downwardly and thereby cause it to be moved into such sealing engagement independently of the load of the weight of the well pipe,

means on said pipe hanger means engageable with a portion of said bore for partial support of the pipe hanger means upon movement of said pipe hanger means downwardly in said bore to a predetermined position,

and retractable means extending through the wall of said body into said bore and engaging and partially supporting said pipe hanger means at said predetermined position.

2. Apparatus comprising:

a wellhead body having a substatially cylindrical vertical bore therethrough and a wall around said bore,

a casing hanger in said bore adapted to support a well casing therebelow,

a tubing hanger in said bore above the casing hanger adapted to support at least one tubing string within the well casing,

seal means above and supported by said tubing hanger positioned to sealingly engage said vertical bore and a tubular member extending upwardly from said tubing string, upon being vertically compressed,

means on said body engageable with said seal means to compress it downwardly and thereby cause it to be moved into such sealing engagement -independent ly of the load of the weight of the tubing string,

said tubing hanger including means engageable with said bore for partial support of the tubing hanger at a predetermined position and also independent of the position of the casing hanger,

and retractable means extending through the wall of said body into said bore and engaging and partially supporting said tubing hanger at said predetermined position.

References Cited UNITED STATES PATENTS 2,254,752 9/1941 Penick et al. 285141 3,004,778 10/1961 Williams et al. 285-142 3,134,610 5/1964 Musolf 16688 3,177,942 4/1965 Haeber 16689 3,248,132 3/1966 Pierce 285-141 CHARLES E. OCONNELL, Primary Examiner.

JAMES A. LEPPINK, Assistant Examiner.

US. Cl. X.R. 16688

Claims

1. APPARATUS COMPRISING: A WELLHEAD BODY HAVING A SUBSTANTIALLY CYLINDRICAL VERTICAL BORE THERETHROUGH AND A WALL AROUND SAID BORE, PIPE HANGER MEANS POSITIONED WITHIN SAID BORE, MEANS ON SAID PIPE HANGER MEANS TO SUPPORT A WELL PIPE THEREBELOW, SEAL MEANS ABOVE AND SUPPORTED BY SAID PIPE HANGER MEANS POSITIONED TO SEALINGLY ENGAGES SAID VERTICAL BORE AND A TUBULAR MEMBER EXTENDING UPWARDLY FROM SAID WELL PIPE, UPON BEING VERTICALLY COMPRESSED, MEANS ON SAID BODY ENGAGEABLE WITH SAID SEAL MEANS TO COMPRESS IT DOWNWARDLY AND THEREBY CAUSE IT TO BE MOVED INTO SUCH SEALING ENGAGEMENT INDEPENDENTLY OF THE LOAD OF THE WEIGHT OF THE WELL PIPE, MEANS ON SAID PIPE HANGER MEANS ENGAGEABLE WITH A PORTION OF SAID BORE FOR PARTIAL SUPPORT OF THE PIPE HANGER MEANS UPON MOVEMENT OF SAID PIPE HANGER MEANS DOWNWARDLY IN SAID BORE TO A PREDETERMINED POSITION, AND RETRACTABLE MEANS EXTENDING THROUGH THE WALL OF SAID BODY INTO SAID BORE AND ENGAGING AND PARTIALLY SUPPORTING SAID PIPE HANGER MEANS AT SAID PREDETERMINED POSITION.