US3171489A

US3171489A - Wellhead apparatus

Info

Publication number: US3171489A
Application number: US192174A
Authority: US
Inventors: Charles M Cole; Paul E Bickel; Jr William W Word
Original assignee: Armco Inc
Current assignee: Armco Inc
Priority date: 1962-05-03
Filing date: 1962-05-03
Publication date: 1965-03-02
Anticipated expiration: 1982-03-02

Description

March 2, 1965 c. M. COLE ETAL 3,171,489

WELLHEAD APPARATUS Filed May 3, 1962 3 Sheets-Sheet 1 Fig.4

INVENTORS CHARLES M- COLE. PAUL E. BICKEL. BYWILL/AM w W020, .112.

March 2, 1965 PAUL, BY WILLIAM w W020, J/z

United States Patent 3,171,489 WELLHEAD APPARATUS Charles .M. Cole, Dunnville, Ontario, Canada, Paul E. Biclrel, Villa Park, Ill., and William W. Word, .lr., Houston, Tex., assignors, by direct and mesne assignments, to Armco Steel Corporation, Middletown, Ohio, a corporation of ()hio Filed May 3, 1962, Ser. No. 192,174 8 Claims. (Cl. 166-665) This invention relates to well head apparatus and, more particularly, to an improved well head construction especially adapted for installations where cementing operations are to be carried out after an internal element of the well head, such as a hanger member, has been installed.

In some applications, it is desirable to accomplish cementing of a string of pipe in a well after that string has been suspended in the manner in which it will remain during operation of the well. Thus, for instance, it is desirable in some cases to first completely run in and suspend a string of production casing, with the casing supported from the well head by the hanger member which is to remain in the well head during operation of the well, and then to cement the production casing. Cementing is ordinarily accomplished by pumping the cement composition through the casing string, an operation which causes well fluid to rise in the annular space surrounding the string of easing. Since the hanger member from which the casing string is suspended is sealed both to the casing and to the surrounding well head structure, some provision must be made for escape of the rising fluid around the casing string. Such fluid flow could, of course, be permitted by displacing the hanger member upwardly in the well head, but this is an unsatisfactory solution because, for example, it requires timeconsuming manipulation of the well head parts.

A general object of the invention is to provide a well head construction capable of allowing upward escape of fluid through an internal member, such as a hanger member, after that member has been finally installed in sealed relation with respect to the surrounding well head structure.

Another object is to provide a valve-equipped well head member.

A further object is to provide a well head construction of the type described embodying valve means which can be operated from a remote point above the well in order to selectively open and close flow ducts through one of the internal well head elements.

In order that the manner in which these and other objects are attained in accordance with the invention can be understood in detail, reference is had to the accompanying drawings, which form a part of this specification, and wherein:

FIG. 1 is a vertical sectional view of a well head apparatus in accordance with one embodiment of the invention;

FIGS. 2, 3 and 4 are transverse sectional views on lines 2-2, 3-3 and 44, FIG. 1, respectively; and

FIG. 5 is a fragmentary vertical sectional view of a portion of the apparatus of FIG. 1, illustrating the manner in which latch members employed therein are disengaged.

Turning now to the drawings in detail, it will be seen that the embodiment of the invention here illustrated comprises a casing head body member 1 provided with an upright passage 2 which accommodates a hanger member 3. Hanger member 3 has an upright bore 4 in which is disposed a tubing string supporting element or mandrel 5. Lower end portion 6 of body member 1 is exteriorly threaded or otherwise suitably adapted for attachment to the top of the last piece of surface casing (not shown).

ice

Top portion 7 of body member 1 is connected, as by external threads as shown, to the sub 8 carried at the bottom end of conductor casing 9. Bore 4 of hanger member 3 is interiorly threaded at its lower end and there is secured therein the upper end of the last piece of production casing 10. Top portion 11 of hanger body 3 is externally threaded for attachment, by sub 12, to a handling joint 13. Supporting element 5 has a vertical throughbore 14 which is threaded at both ends, the last joint 15 of the tubing string being secured in the lower threaded portion of bore 14 and any suitable flow device 16 being secured in the upper threaded portion of bore 14. Near its mid-point, passage 2 has a portion of reduced diameter, providing an upwardly facing, downwardly and inwardly tapering, frusto-conical seat 17. At its bottom end, hanger member 3 is formed with a downwardly facing, downwardly and inwardly tapering, frusto-conical surface 18 adapted to engage seat 17 in face-to-face contact, so that the hanger member can be securely supported by body member 1. Above seat 17, portion 19 of passage 2 extends as a right cylindrical surface interrupted only by a transverse annular groove 20. Opening inwardly of the body member 1, groove 20 has a flat top wall 21 lying in a plane at right angles to the axis of passage 2. The upper end portion of passage 2 is enlarged, tapering upwardly and outwardly at 22.

Above surface 18, hanger member 3 has a right cylindrical outer surface which is of such length that, when the hanger member is engaged with seat 17, the body of the hanger member substantially completely fills the space enclosed by cylindrical portion 19 of passage 2, as will be evident from FIG. 1. Hanger member 3 also has an intermediate portion presenting an outer surface of right cylindrical configuration indicated at 23, the diameter of surface 23 being materially smaller than the diameter of cylindrical portion 19 of passage 2, so as to provide an annular space between hanger member 3 and portion 19 of passage 2 when the hanger member is seated as shown in FIG. 1. At a point which is aligned with groove 29 when surface 18 of hanger member 3 engages seat 17, the hanger member is provided with an outwardly opening, radially extending, cylindrical bore 24. A latch pin 25 is slidably disposed in bore 24.

Latch pin 25 has a cylindrical body 26 which is shorter than the depth of bore 24 and which has an outer diameter of such size that the latch pin slidably engages the wall of bore 24. A guide pin 27 projects upwardly into bore 24, being fixed to hanger member 3 and extending radially with respect to the bore. Latch pin 25 is provided with a longitudinally extending guide slot 28 which opens outwardly and receives guide pin 27, so that the latch pin 25 is retained in a predetermined orientation. In an area which, as a result of cooperation of guide pin 27 and slot 28, is maintained as an upper portion of latch pin 25, the latch pin is cut away to provide a horizontal flat surface 29 and an upwardly and inwardly slanting cam, surface 30. Body 26 of the latch pin is provided with an axially extending bore 31 which accommodates a helical compression spring 32, the effect of the spring being to bias the latch pin outwardly relative to hanger member 3. The bottom of the outer end portion of the latch pin is chamfered or cut away to provide a downwardly and inwardly slanting surface, as indicated at 33, so that the tip of the latch member is of such dimension, axially of hanger member 3, as to be accommodated within groove 20. The location of bore 24, and the position of flat surface 29, is such that, when surface 18 of hanger member 3 is engaged with seat 17, surface 29 of the guide pin is aligned in a plane just below the plane occupied by top wall 21 of the groove, so that the tip portion of the latch pin can move outwardly into the groove.

When hanger member 3 is inserted downwardly into passage 2, it will be understood that the tip of latch pin 25 projects radially outwardly from the hanger member to such an extent that, as the hanger member is lowered, the tip of the latch pin will ride along frusto-conical portion 22 of the passage, so that the latch pin iscammed inwardly. Further lowering of the hanger member causes the tip of the latch pin to ride along cylindrical portion 19'of passage 2. As the hanger member is seated,

the tip of the latch pin passes below top wall 21 of groove 20, and the latch pin snaps outwardly into the groove, so that surface 29 is engaged below wall 21 and the hanger member is latched in its seated position.

Bore 4 of hanger member 3 is also provided with a portion of reduced diameter presenting an upwardly facing, downwardly and inwardly slanting, frusto-conical seat 34. Above seat 34, the wall of bore 4 extends as a plain cylinder. The lower portion of mandrel is of such diameter as to substantially completely fill that portion of bore 4-above seat 34. At its lower end, mandrel 5 is provided with .a downwardly and inwardly tapering, frusto-conical surface 35 disposed to engage seat 34 in face-to-face contact for support of the mandrel on hanger member 3. The Wall of bore 4 is interrupted, above seat 34, by an inwardly opening transverse annular groove 36 having a flat top wall 37 lying in a plane at right angles to the axis of the mandrel 5. Mandrel 5 is provided with a radially extending, outwardly opening bore 38 accommodating a latch pin 39 which is identical in all respect to latch pin 25. Thus,: latch pin 39 has an upwardly facing, horizontal, fiat tip surface 40 disposed just below top 'wall 37 of; groove 36- when the mandrel is engaged with seat 34. Latch pin 39 also has a downwardly and inwardly slanting lower tip surface 41 disposed to come into engagement with the top of hanger member 3 as the mandrel is lowered shown.

' extendingcircularly and lying in a plane at right angles tothe' axis of the adaptor, .the axial length of the skirt being such that, when the adaptor has been completely made up on the hanger member, as shown, the tip of the skirt is located in the plane occupied by fiat surface 29 of the latch pin. It will be understood that the retrieving adaptor is engaged with the hanger member at a time when the hanger member occupies the seated position illustrated in FIG. 1 and is latched in place. Accordingly, as the retrieving adaptor isthreaded onto therhanger member, the tip of skirt 47 moves down wardly into engagement with cam surface 30 of the latch pin. Because of this engagement, continued downward movement of skirt 47 causes the latch pin to be cammed progressively inwardly until, when the adaptor has been fully installed, thelatch pin 25 occupies the position seen into the hanger member, surface 41 serving to cam the A latch pin 39 inwardly in bore 38 so that the tip of the latch pin can ride along the plain cylindrical upper portion of bore 4 until the mandrel is seated," whereupon the latch pin is spring-biased outwardly into engagement in groove 36 in the manner hereinbefore described with reference to latch pin 25. A

FIG. 1 illustrates the hanger member 3 after it has been landed, by manipulation of handling point 13, with the handling joint and sub 12 still in place. For removal of handling joint 13, it is necessary that the threaded connection between sub 12 and the upper end portion of hanger member 3 be disengaged and this, of course, can only be accomplished by rotation of the handling joint while the hanger member is held against rotation. To make this possible, a stop pin 44 is provided, being driven into a suitable radially extending bore through the cylindrical wall of groove 20, the arrangement being such that the head of the stop pin 44 substantially fills groove 20. Accordingly, if the hanger member 3, once being seated, rotates on its seat, latch pin 25 will come into engagement with the headof stop pin 44 and. prevent further rotation of the hanger member. It will thus be seen that the stop pin 44 coacts with latch pin 25 to hold the hanger member against rotation and so enable the operators to unscrewthe handling joint. A stop lug 45 is welded in groove 36 to cooperate with latch pin 39, preventing rotation of mandrel 5, in the samemannerjust described.

FIG. 5 illustrates the manner in which latch pin 25 can be dis'engagedin order to allow removal'of hanger member 3. For this purpose, the handling string terminates in a retrieving adaptor 46 having internal threads adapted to cooperate with the externally threaded upper portion of the hanger member. Retrieving adapter 46 also has a cylindrical skirt 47 of such diameter as to closely embrace the intermediate cylindrical surface 23 of the hanger member when the retrieving adaptor has been completely made up on the hanged member, as.

approximately. seated.

in FIG. 5 and is fully retracted from groove 20. With the latch pin in thisposition, hanger member 3 can now be Withdrawn upwardly from passage 2, by manipulation ofthe handling string; It will be understood that a similar, smaller retrieving. adapter (not shown) canbe engaged over the threaded upper end 'of mandrel 5 in order to cause retraction of latch pin 39," in the same I manner just described.

the well, whether the hanger member and mandrel have been properly seated.

In this connection, it will be understood-by those skilled in the art that, as the production casing string is lowered, an obstruction may be encountered at a-time when the hanger member 3 is Movement of the string .downwardly thus stops, and it could be assumed that the hanger member has engaged seat 17. There is thus an ambiguity, insofar as the situationappea'rs to the operators,. since the operators cannot tell'for certain whether seating has beenaccomplished or an obstruction encountered. Under these circumstances, an upward strain applied to the handling string will be opposed by engagement of surface 29 with the top wall 21 of groove 20 if the hanger member is actually properly seated'so that the latch pin 25 is engaged in'groove 20. Such en-' gagement is observable because the load applied via the handling string will be in excess of the weight of the producting casing string. If, on the other hand, hanger member'3 has not been properly seated, .then latchpin 25 willnot be engaged in groove 20 and only the weight of the production casing. string will oppose the upward force applied to the handling string. The difference in loads existing for the two situations is observable by the operators at their location remote from the well head and serves as a positive indication as to whether or not the hanger member is in fact seated properly in body member 1.. Latch pin 39 servesin the samegeneral fashion to allow the operators to determine whether or not mandrel 5 is properly seatedon the hanger member.

V The second function'servedby the latch pins is to I secure the hanger member and the mandrel positively in place against fluid pressures existing inthe well. Thus,

so long as latch pin 2-5is properly engaged in groove 20,

head construction is to be subjected to very high well pressures. Thus, two diametrically opposed latch pins can be employed, or three latch pins can be employed, with equal angular spacings therebetween.

Hanger member 3 is provided with a plurality of vertical flow ducts 4-8 and a plurality of angularly spaced vertical bores 49, each bore 49 having an upper portion 50 of larger diameter and a lower portion of smaller diameter. A plurality of bolts 51 extend downwardly each through a different one of the bores 49, the length of the bolts being such that, when the bolt heads engage the shoulder 52 between the upper and intermediate portions of the hanger member 3, the tips of the bolts project well below bottom face 53 of the hanger member. A helical compression spring 54 is disposed about each bolt 51 in the larger diameter bore portion 50, springs 54 being engaged between the bolt head and the shoulder at the bottom of bore portion 50 in each case.

Below hanger member 3, an annular movable valve plate 55 surrounds casing it). Plate 55 has a flat upper face 56 adapted to engage bottom face 53 of the hanger member,

circular grooves

57 and 58, concentric with the circular opening of the valve plate, being provided to accommodate sealing rings 59 and 60, respectively. The radial spacing between

grooves

57 and 58 is greater than the diameter of flow ducts 48 and the ducts 48 are so located that, when valve plate 55 engages the hanger member, the lower ends of all of the ducts 48 are disposed between sealing rings 59 and 60 and therefore excluded from communication with the annular space between the production and surface casings.

The threaded tips of bolts 51 are each engaged in interiorily threaded upwardly opening bores 61 in valve plate 55 so that the valve plate is suspended from the hanger member via the bolts. The lengths of bolts 51, and the normal or extended dimensions of springs 54, are such that, assuming that the bolts are free to move upwardly relative to the hanger member, the springs are effective to bring the valve plate simultaneously into engagement with the hanger member so that good seals are accomplished by sealing rings 59 and 60.

From FIG. 1, it will be observed that the heads of bolts 51 are disposed immediately adjacent to the upper portion ll of hanger member 3 to which sub 12 is to be attached. The proportions of sub 12 are such that, when the same is fully made up on the hanger member, lower end face 62 of the sub is disposed at a point near shoulder 52, such point being well below the transverse plane occupied by the tops of the bolt heads when springs 54 are relaxed. Hence, installation of sub 12 serves first to engage end face 62 with the heads of bolts 51 and then to force the bolts downwardly until the bolt heads engage shoulder 52. and valve plate 55 is spaced well between lower face 53 of the hanger member. With the valve plate in this position, flow ducts 48 are open at their lower ends for communication with the space between the production and surface casings. Ducts 43 are also open at their upper ends via the space between shoulder 52 and end face 62 of sub 12, for communication with the annular space between the conductor casing or riser 9 and the handling string.

Accordingly, when the handling string is manipulated to land the hanger member, flow ducts 48 are open and there is free communication between the space between the production and surface casings, on the one hand, and the space between the conductor casing and handling string, on the other. So long as the handling string is left attached to the hanger member, engagement of end face 62 of sub 12 serves to maintain valve plate 55 in its open position so that flow ducts 48 remain open. Accordingly, before installation of mandrel 5 when the tubing string is run in, cement can be pumped downwardly through casing 19 for cementing of the casing, Well fluid being free to pass upwardly between the production and surface casings, through ducts 48 in the hanger member, and then upwardly between the conductor casing and the handling string. When the cementing operation has been completed, removal of the handling string, with its sub 12, allows springs 54 to actuate valve plate 55 to its closed position.

Typically, the embodiment of the invention illustrated is useful in applications where the well head is to be installed at the floor of a shallow body of water, the operation being carried out from a floating vessel or fixed platform. Body member 1 is fixed to the top of the last joint of the surface casing and run down with sub 3 and conductor casing or riser 9 attached thereto as shown. With the surface casing string completed, so that the body" member 1 is in its final position, hanger member 3 is then installed. Preliminarily, the hanger member is fixed to the top of the last joint of production casing, and sub 12 is made up on the top of the hanger member so that bolts Sl are depressed and valve plate 55 is in the open position seen in FIG. 1. The production casing string, with the hanger member thereon, is now further lowered by manipulating the handling joint until the string comes to a stop. Assuming that this occurs because of seating of the hanger member on seat 17, latch pin 25 will spring outwardly and engage the groove 20. That this has occurred can be determined by applying an upward force to the handling string, as hereinbefore described. The production casing is now cemented by pumping the cement composition down the production casing, well fluid being allowed to pass upwardly through the open flow ducts 48 in the hanger member. Sub 12 is now retrieved by rotating the handling string, causing latch pin 25 to come into engagement with stop pin 44 in groove 2%), so that the hanger member cannot rotate and rotation of the handling string will unscrew the sub. Removal of the handling string and sub 12 allows springs 54 to actuate valve plate 55 to its closed position so that upward flow of fluid through flow ducts 48 is then precluded. Latch pin 25, engaged in groove 20, act to prevent upward displacement of the hanger member.

The well is now hydraulically fractured in conventional fashion. Mandrel 5 is then attached to the last joint of the tubing string and a handling joint is made up on the top of the mandrel. The tubing string is then lowered, the operator again observing when downward motion ceases. Assuming that lowering of the tubing string terminates because of seating of the mandrel on seat 18, latch pin 39 will spring outwardly into groove 36, latching the mandrel in place. The operators again test for seating by applying an upward strain on the handling string, as hereinbefore described. Further well completion steps can be carried out in conventional fashion.

A good fluid seal is established between hanger member 3 and the cyindrical wall portion 19 of passage 2 by a sealing ring 63 disposed in an outwardly opening transverse annular groove in the hanger member immediately above seat-engaging surface 18. A seal is provided between the top of body member 1 and sub 3 by a sealing ring 64 disposed in a downwardly opening groove located in a portion of the sub opposed to the top end face of body member 1, as seen in FIG. 1.

While one particularly advantageous embodiment of the invention has been chosen for illustrative purposes, it will be understood by those skilled in the art that various changes and modifications can be made therein without departing from the scope of the invention as defined in the appended claims.

What is claimed is:

1. In a well head construction, the combination of a body member having an upright passage therethrough;

a support member adapted to be fixed to a string of pipe to be suspended from the well head,

said support member being dimensioned for downward insertion into said passage, said body member and said support member having cooperating shouldermeans engaged to supof said body member, and a lower annular space,

surrounding the suspended pipe, when said support member is installedin said body member,

said support member having flow duct means extending upwardly therethrough to communicate, when open, between said upper and lower annular space;

movable valve means carried by said support member for movement between a first position, in which it opens said fiow duct means and a second position, in which it closes said flow duct means; and V yieldable means biasing said movable valve means to said second position,

said movable valve means being so constructed and arranged as to present an upwardly facing element for engagement from above said'support member to actuate said movable valve means to said first position. 2. A well head construction in accordance with claim and wherein said support member is a casing hanger member having an upright bore for communication with the casing to be suspended therefrom,

annular sealing means being provided to seal between said hanger member and' said body 7 member, 7 V said flow du'ct means extends through said hanger member in at least one area located radially out: wardly from said bore, and said movable valve means comprises an annular valve member, and means vertically slidable in said hanger member and attached to said valve member to suspend the same below said hanger member,

said valve member carrying upwardly facing sealing means disposed to engage said hanger member and establish a seal around said flow duct means. 1 t

3. A'well head construction in accordance with claim 2 and wherein 4. A well head construction in accordance with claim 2 and wherein said hanger member includes an upwardly said hanger member immediatelyltherebelow, said top portion joining the adjacent portion of said hanger member at a transverse shoulder,

said hanger member being provided with a pluprojecting top portion of smaller'diameter than the portion of' rality of angularly spaced vertical bores extendsaid value member is in said second position, whereby said elongated elements can be depressed from above to move said valve member to said first position.

5; A wellhead construction in accordance with claim 4 and wherein said top portion of said hanger member is threaded for attachment to a'handling device, and

said elongated elements are so located as to be engaged and depressed by the handling device when the latter is attached to said top portion.

6. In a well headapparatus, the combination of a body member having an upright passage thercthrough;

a hanger member having an upright bore for communicationwith a string of pipe to be suspended from said hanger member, said hanger member having at least one flow duet extending upwardly therethrough,

said hanger member being dimensioned for downward insertion into said passage,

said body and hanger members having cooperating shoulder means engaged to support said hanger member on said body member when said hanger member is inserted into said passage,

said hanger member being sealed in fluid-tight relation to the wall of said passage when said shoulder means is engaged to support said hanger member,

said hanger member having at least one vertical bore therethrough outwardly of said upright bore; 1

an elongated 'memberextending slidably through said vertical bore;

a movable valve member disposed below said hanger member and fixed to said elongated member, said valve member being engageable with said hanger member to close said flow duct, said elongated'member projecting freely above the upper end of said vertical bore when said'valve member is engaged'with said hanger member;

and resilient means engaged between said elongated member and said hanger member to bias said elongated member upwardly, whereby said valve member is t biased to engage said hanger member and close said flow duct,

said elongated. member being engageable from above said hanger member, when said hanger member has been seated in said passage, for

depression against the biasing action of said resilient means, to move said valve member downwardly to open said flow duct,

7. In a well head construction adapted for underwater installation, the combination of a tubular member having an upright passage therethrough; a hanger member having an upright bore for communication with a string of pipe to be suspended from said hanger member,

said hangerrmem'ber being dimensioned fordownward insertion into said passage, said tubular member andsaid hanger member having cooperating shoulder means engaged to support' said hanger member on said tubular member when said hanger member is inserted into said passage, said hanger member being sealed in fluid-tight relation to the wall of said passage when said shoulder means is engaged to support said hanger member, said hanger member having at least one flow duct extending upwardly therethrough to communicate, when open, between the space above. said hanger member and the space surrounding the string of pipe below said hanger member; and valve means mounted on said hanger member for movement between a first position, in which it opens said flow duct, and a second position, in which it. closes said flow duct,

said valve means normally occupying one of said first and second positions, said hanger member having an upper portion of smaller transverse dimension than said passage, and said valve means including at least one element which is located in the space between said upper portion of said hanger member and the wall of said passage and which is upwardly exposed, whereby remote actuation of said valve means from said one of said positions to the other thereof can be accomplished by means of an actuating tool moved downwardly to surround said upper portion of said hanger member and operatively engage said upwardly exposed element of said valve means. 8. In an underwater Well installation, the combination of a head member having an upright passage therethrough; a hanger member having an upright bore,

said hanger member being dimensioned for downward insertion into said passage, said head member and hanger member having cooperating shoulder means engaged to support said hanger member on said head member when said hanger member is inserted into said passage, said hanger member being sealed in fluid-tight relation to the wall of said passage when said shoulder means is engaged to support said hanger member; a well pipe fixed to said hanger member and depending therefrom,

said hanger member having an upright bore communicating with the interior of said well pipe; conductor casing secured to said head member and extending upwardly therefrom,

said hanger member having an upper portion spaced inwardly from said conductor casing,

said upright bore extending through said upper portion;

a tubular member connected to said upper portion of said hanger member and extending upwardly therefrom within said conductor casing,

said upright bore communicating with the interior of said tubular member,

there being an annular space above said hanger member between said conductor casing and said tubular member,

said hanger member having flow duct means extending therethrough outwardly of said upright bore and communicating between the space outside of said well pipe below said hanger member and said annular space above said hanger member, whereby well fluid outside of said well pipe can pass upwardly through said hanger memher and into said annular space when said flow duct means is open; and

valve means mounted on said hanger member for movement between a first position, in which it opens said flow duct means, and a second position, in which it closes said flow duct means,

said valve means normally occupying one of said first and second positions,

said valve means including at least one upwardly exposed element disposed outwardly of said upper portion of said hanger member for engagement by an actuating tool carried by said tubular member, whereby said valve means can be actuated to the other of said positions by manipulating said tubular member and tool from a location above and remote from said head member.

References Cited by the Examiner UNITED STATES PATENTS 2,080,610 5/37 Humason l66-87 2,212,036 8/40 Otis 166-86 2,476,172 7/49 Williams 285-317 X CHARLES E. OCONNELL, Primary Examiner.

Claims

1. IN A WELL HEAD CONSTRUCTION, THE COMBINATION OF A BODY MEMBER HAVING AN UPRIGHT PASSAGE THERETHROUGH; A SUPPORT MEMBER ADAPTED TO BE FIXED TO A STRING OF PIPE TO BE SUSPENDED FROM THE WELL HEAD, SAID SUPPORT MEMBER BEING DIMENSIONED FOR DOWNWARD INSERTION INTO SAID PASSAGE, SAID BODY MEMBER AND SAID SUPPORT MEMBER HAVING COOPERATING SHOULDER MEANS ENGAGED TO SUPPORT SAID SUPPORT MEMBER ON SAID BODY MEMBER WHEN SAID SUPPORT MEMBER HASA BEEN INSERTED INTO SAID PASSAGE. SAID SUPPORT MEMBER HAVING A BODY PORTION SUBSTANTIALLY COMPLETELY FILLING SAID PASSAGE WHEN SAID SUPPORT MEMBER IS DISPOSED WITH SAID SHOULDER MEANS IN ENGAGEMENT, AND AN UPPER PORTION OF REDUCED TRANSVERSE CROSS SECTION DISPOSED ABOVE SAID BODY PORTION, THERE BEING AN UPPER ANNULAR SPACE, SURROUNDING SAID UPPER PORTION OF SAID BODY MEMBER, AND A LOWER ANNULAR SPACE SURROUNDING THE SUSPENDED PIPE, WHEN SAID SUPPORT MEMBER IS INSTALLED IN SAID BODY MEMBER, SAID SUPPORT MEMBER HAVING FLOW DUCT MEANS EXTENDING UPWARDLY THERETHROUGH TO COMMUNICATE, WHEN OPEN, BETWEEN SAID UPPER AND LOWERANNULAR SPACE; MOVABLE VALVE MEANS CARRIED BY SAID SUPPORT MEMBER FOR MOVEMENT BETWEEN A FIRST POSITION, IN WHICH IT OPENS SAID FLOW DUCT MEANS AND A SECOND POSITION, IN WHICH IS CLOSES SAID FLOW DUCT MEANS; AND YIELDABLE MEANS BIASING SAID MOVABLE VALVE MEANS TO SAID SECOND POSITION, SAID MOVABLE VALVE MEANS BEING SO CONSTRUCTED AND ARRANGED AS TO PRESENT AN UPWARDLY FACING ELEMENT FOR ENGAGEMENT FROM ABOVE SAID SUPPORT MEMBER TO ACTUATE SAID MOVABLE VALVE MEANS TO SAID FIRST POSITION.