US2207471A - Casing head - Google Patents

Description

July 9, 1940;. J. R. YANCEY I 7 2,207,471

' I CASING HEAD Filed Jan. 27, 1940 2 Sheets-Sheet 1 Patented .iuly 9,1940

a v CASDIG HEAD John B. Yancey, Houston, Tex, assignmto Gray Tool Company, Houston,

of Texas Tea, a corporation Application January 27, 1940, Serial No. 316,012

'1 Claims.

vide a novel association of the parts mentioned above resulting in a strong and efficient support for the well casing, as well as the other parts which are mounted above the foundation ring.

Heretofore in the art, it has been customary to rigidly attach the first or outermost string of casing to the landing base, or foundation ring, rather than hanging said casing therein.

It has further. been the custom inthe prior art, w to sometimes attach the upper end of the first or outermost casing to a casing head, the latter being supported on the foundation ring.

In the present invention, I provide a novel construction wherein a new type of hanger en- 35 compasses the outermost string of casing, which hanger is supported by a seat in the foundation ring. The hanger referred to is designed with an outside sealing surface which engages a corresponding surface on the inside of a tubular casing head mounted on the foundation ring. With this construction, the hanger is supported in the foundation ring, and the casing head retains the hanger in its seat, and forms a seal therewith.

Another principal object of the invention is to 88 provide a novel foundation ring and easing hanger seated therein, which hanger, when installed, projects upwardly above the foundation ring, so that the casing to be supported by the hanger can be conveniently welded thereto from superstructure, partially in section, showing the 50 manner in which the outermost string of casing,

and one inner string thereof, is supported,

Figure 2 is a similar view, showing only a portion of the equipment, which displays a modified means for connecting the hanger with the outermost casing,

Figure-3 is a view similar to Figure 2 showing a further modification, 1

- Figure 4 is a side elevational view of a portion of the apparatus of Figure 1. This view shows an intermediate stage in the building of a well 5 I using the present invention, and

Figure-5 is a horizontal sectional along the line 55 of Figure 4;

'Referring to Figure 1, the landing base or foundation ring is shown at "3.. This ring comprises a relatively wide circular one-piece flange adapted to be supported on the ground at the surface of the well, usually on cement (not shown) to which it may be secured as by means, of bolts.

The foundation ring is strengthened by means of radial webs l2, and has a central vertical bore it therethrough, which bore includes an enlarged upper portion l6 meeting the smaller portion id in a ledge l8, which constitutes a hanger seat.

Extending upwardly through the central bore of the foundation ring, is the first or outermost string of casing 22. The upper end of said string of casing is encompassed by a tubular hanger 28, the lower end of which rests on the ledge it of the foundation ring. The outer diameter of the hanger 24 is designed to seat within the enlarged portion l6 of the bore through the foundation ring. The outer surface of the hanger is conically tapered upwardly and inwardly adjacent its upper end as at 26', and this tapered surface is provided with one or more circular grooves extending around the hanger and containing packing 28.

As is well known in the art, wells are built by drilling into the earth a predetermined depth short of the sought for pressure sands, after which the first or outer string of casing is run into the drilled hole and cemented. After this has been done, and practicing the persent inven tion, the foundation ring Ill is lowered downwardly over the upper end of the outermost string of casing and positioned on. the cement base which usually surrounds the well. Thereafter,

the 'hanger 24 is lowered over theupper end of the casing and positioned on its seat I8. At this time, a strain may be take on the casing with the derrick equipment, and the casing may be welded to the upper end of the hanger as at 30, the bore of the hanger being beveled adjacent its upper end in order to receive the metalof the weld. It will be evident that the welding may be easily effected, as the parts to be connected are conveniently exposed. The hanger and foundation ring are so formed that the hanger projects view, taken upwardly out of the bore of the foundation ring.

By the arrangement shown, the casing may be welded to the hanger from the outside, resulting in a more easily performed and better weld, and one more convenient to inspect. Thereafter, the casing which extends abovethe hanger is cut off as at 32.

Packing is not required between the hanger 24 and the foundation ring, for the outermost casing 22 in most cases does not traverse formations having fluid under pressure. Furthermore, there would be no way to control pressures outside the casing 22, if such existed, and this outermost casing is usually cemented from top to bottom.

When the casing has thus been landed and welded, a one piece tubular casing head 34 is mounted on the foundation ring, as shown in Figure 4, and is secured thereto as by means of bolts 36 which extend through the lower flange 38 of the casing 'head and into threaded sockets 40 which are integral with the foundation ring. The casing head 34 is substantially the same as that shown in the patent to Mueller et al., 2,082,413, June 1, 1937, having an inside surface 4| adjacent the lower end of its bore, tapered in a manner corresponding w th the outside surface 26 of the hanger 24. When the casing head 34 is bolted to the foundation ring, it serves to retain the hanger 24 in its seat while forming a seal with the outer surface thereof, and thereby retaining the outermost string of casing 22 in place. The seal between the hanger and the casing head is necessary, as the second or inner casing may have traversed pressure zones of the well formation. Because the casing head 34 is used to retain the hanger in place, no separate locking device or ring, to retain the hanger, is required.

It will be noted that the casing head 34 has an inside bore as wide as that of the casing 22. It also has an upper inside tapered seat 42 to receive the lower tapered sealing surface of a hanger 44, which hanger is adapted to be connected in any suitable manner with the second or inner string of casing 46.

when the casing head 34 has been secured on and above the foundation ring as previously described, drilling is continued through the outermost casing 22 and then the inner casing is lowered into the well with the hanger 44 attached thereto, and supported in the seat 42 of the casing head 34 in a now well known manner. These operations may be performed while com-- plete mechanical control of the well is maintained, as described in Patent Number 2,117,444,

- Mueller et al., May 17, 1938, The casing head .34 has the usual side outlets below its seat 42,- flow through one of which may be controlled by a valve 48, while the other outlet may be closed by a bull plug 50.

The hanger 44 is of a type generally similar to that described in the aforementioned Patent Number 2,082,413, having both lower and upper tapered sealing surfaces. When the hanger 44 is landed, as shown in Figure l, a tubing head 52 is secured on and above the casing head 34, forming a seal with the upper surface of hanger 44. The tubing head 52 also has an upper inside tapered seat (not shown), which receives a hanger carried by the upper end of the tubing 54 which is lowered into the well after the drilling in" operation, as described in Patent No. 2,150,887, Mueller et al., March 14, 1939. The upper flange of the tubing head 52 is adapted to connect with the flow control valve 56 of the Christmas tree, as described in the preceding Mueller et a1. patent. The tubing head 52 also has conventional side outlets below its tubing hanger seat, one of which may be controlled by a valve, and the other closed by a plug and pressure gauge, as shown in Figure 1.

In Figure 2, a modified type of hanger i0 is illustrated, the bore through this hanger being upwardly and outwardly tapered as at 62 to receive a plurality of serrated slip segments 64. The chamber in the hanger, and the slips therein, may be formed as disclosed in the application of Richard T. Roye, Serial No. 248,301, filed January 4, 1939. The hanger 60 may be moved downwardly over the upper end of the casing 22, as previously described, and when an upward strain is taken on the casing by the derrick equipment, the slips will hold the strain while the weld 30 is being made, as previously described. Thereafter, the upper end of the casing may be cut off as at 32 and the procedure outlined above carried through to complete the well.

In Figure 3 a hanger 66 is shown, similar to that of Figure 1, except that it is interiorly threaded as at 68 to connect with the upper end of the casing 22. -This type of hanger is rigidly connected to the casing before it is lowered onto the seat I8 of the foundation ring 10, and obviously, no welding is required. When this hanger is landed, the procedure previously described is then carried out.

It will be apparent that I have provided a very simple, compact, yet rugged and efficient casing head construction to support well casing from a foundation ring. As previously described, the outermost casing is encompassed by a separate hanger, which is supported in a seat of the foundation ring. The hanger is retained in place by the engagement of the casing head with its outside surface, and sealing means between the outside surface of the hanger and the inside surface of the casing head provides an effective seal preventing any escape of fluid or gas from the well.

It will be apparent that various changes may be made in the constructions disclosed herein without departing from the invention.

I claim:

1. A casing head for wells comprising a relatively wide foundation ring having a central vertical opening therethrough, a hanger seat around said opening, a tubular hanger adapted to be connected with the first string of well casing supported in said seat, and a tubular casing head adapted to support an inner string of easing mounted on and above said foundation ring engaging said hanger adjacent the upper end thereof to retain the same in said seat.

2. A casing head for wells comprising a relatively wide foundation ring having a central vertical opening therethrough, a hanger seat around said opening, a tubular hanger adapted to be connected with the first string of well casing supported in said seat, said hanger having an outside sealing surface adjacent its upper end, a tubular casing head adapted to support an inner string of easing mounted on and above said foundation ring engagingsaid outside surface of said hanger to retain the same in said seat, and sealing means between said outside surface of said hanger and said casing head.

3; A casing head for wells comprising a relatively wide foundation ring having a central vertical opening therethrough, a hanger seat around said opening, a tubular hanger adapted to be connected with the first string of well casing supported in said seat, said hanger having a tapered outside sealing surface adjacent its upper end and a packing ring extending around said surface, a tubular casing head adapted to support an inner string of casing mounted on and above said foundation ring, said casing head having a correspondingly tapered inside surface adjacent its lower end engaging said outside surface of said hanger to retain the same in said seat, and form a seal therewith.

4. A casing head for wells comprising a relatively wide foundation ring having a central vertical opening therethrough, a hanger seat around said opening, a tubular hanger adapted to encompass the upper end of the first string of well casing supported in said seat, said hanger having means adjacent its upper end for welding the same to the upper end of the first string oi casing, and a tubular casing head adapted to support an inner string of casing mounted on and above said foundation. ring engaging said hanger adjacent the upper end thereof to retain the same in said seat.

5, A casing head for wells comprising a relatively wide foundation rdnghaving a central vertical opening therethrough, a hanger seat around said opening, a tubular hanger adapted to encompass the upper end of the first string of well casing supported in said seat, said hanger having a chamber in its bore and slips therein to support the first string of casing, and means ad-= jacent its upper end for welding said hanger tn the upper end of the first string of casing, and a tubular casing head adapted to supper-t an ten ner string oi casing mounted on and above said foundation ring engaging said hanger adjacent the upper end thereof to retain the same in said seat.

6. A casing head for wells comprising a relatively wide foundation ring having a central vertical opening therethrough, a hanger seat around said opening, a tubular hanger adapted to en-- compass the upper end of the first string of well casing supported in said seat, said hanger having a bore and threads therein to connect with corresponding threads adjacent the upper end of the first string of casing, and a tubular casing head adapted to support an inner string of casing mounted on and above said foundation ring engaging said hanger adjacent the upper end thereof to retain the same in said seat.

7. A casing head for wells comprising a relatively wide foundation ring having a central vertical opening therethrough, a hanger seat around said opening, a tubular hanger adapted to encompass the upper end of the first string of well casing supported in said seat, the upper end oi said hanger projecting upwardly above said foundation ring and having means for welding the same to the first string of easing adjacent its upper end, and a tubmar casing head adapted to support an inner string of easing mounted on and above said foundation ring when the portion of the first string of casing above said weld is removed, said casing head engaging said hmer adjacent the upper end thereof to retain the same in said seat,

semi R. YANCEY.

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