US3393740A - Well-packing head - Google Patents

Description

July 23, 1968 R 55555 ET AL 3,393,740

WELL-PACKING HEAD Filed Feb. 17, 1966 p/ I I I RA r B. 55555 2: PETER R Z/NCHUK A T TORNE V United States Patent 3,393,740 WELL-PACKING HEAD Ray B. Seese, Glenville, W. Va., and Peter P. ZIIICIlllk, Old Bridge, N.J., assignors to Air Reduction Company, Incorporated, New York, N.Y., a corporation of New York Filed Feb. 17, 1966, Ser. No. 528,208 17 Claims. (Cl. 166-84) ABSTRACT OF THE DISCLOSURE This invention relates to an improved casing head for a well. The improved casing head includes a cylindrical threaded portion for connecting it to the upper end of the well, a cover having an opening for a tubing string and a cable line, the cover being split to facilitate assembly and the cover also including packing means to prevent uncontrolled exhaust of gases from the well.

This invention relates to apparatus for removing solid material from an oil, gas or water well. This invention takes the form of an improved casing head which can be easily mounted on the upper end of a well. The head may be split so that it can be assembled around a tubing string and associated cable. The casing head has a cover which includes packing which is radially expandable to effect a gas tight seal with the head and the tubing string and cable.

It is an object of the invention to provide improved apparatus for controlling the release of gas pressure from a well where gas is supplied to the well under high pressure to enter into the interstices of sand or other matter that is causing a drilling or swabbing tool to stick in the well casing. When the gas pressure is suddenly released, this loosens the sand or other material by expansion of the gas and thus releases the tool or swab, as described in the Bryant patent application Ser. No. 449,219 filed Apr. 19, 1965.

Wi h a well casing left open ended when the pressure is suddenly released, oil is sometimes sprayed over the surrounding area. Aside from the annoyance of this experience, it presents a fire hazard, and it has resulted in damage to the pumping and well equipment apparatus by fire.

Another object is to keep the top of the well casing closed during the release of gas pressure and to provide a controlled escape for the gas through a side outlet.

Siill another object is to provide a packing head of the character indicated with provision for attaching it to the upper end of a standard well casing and with provisions for placing the head over existing cable and/or tubing strings that extend down into the casing.

Other objects, features and advantages will appear or be pointed out as the description proceeds.

In the drawing, forming a part hereof, in which like reference characters indicate corresponding parts in all the views;

FIGURE 1 is a diagrammatic view showing a well and casing with a well-packing head, made in accordance with this invention, connected to the top of the casing;

FIGURE 2 is a greatly enlarged side elevation, partly broken away and in sec'ion, showing the packing head of FIGURE 1 without the tubing string and the drilling or swabbing line;

FIGURE 3 is a top plan view of the apparatus shown in FIGURE 2 but with the packing head placed around the tubing string and the drilling or swabbing line as in FIGURE 1;

FIGURE 4 is a view similar to FIGURE 2 but showing 3,393,740 Patented July 23, 1968 "ice a modified form of the invention and showing the tubing string and the drilling or swabbing line;

FIGURE 5 is a top plan view of the apparatus shown in FIGURE 4, but with the top plate removed; and

FIGURE 6 is a sectional view taken on the line 6-6 of FIGURE 4.

FIGURE 1 shows a well 10 having a casing 12 with a head 14 closing the top of the casing. The head 14 has a side outlet 16 through which gas is exhausted from the inside of the casing. Gas under high pressure is supplied to the well 10 from a gas supply unit 18 through tubing string 24.

The escape of gas is prevented by a control valve 20. The cross section of the side outlet 16 and the control valve 20 are sufficient so that when the control valve 20 is opened, the escape of gas from the well is very rapid and the expansion of gas which has entered the interstices of the sand or other solid material in the well expands to loosen any such material which has packed at locations to prevent free movement of a drilling or swabbing tool within the casing.

FIGURE 1 also shows diagrammatically a tubing string 24 and a drilling or swabbing line 26 which extend downward into the casing 12. The head 14 is of such construction that it can be placed around the drilling or swabbing line 26, and the construction for obtaining this result will be explained in connection with the larger scale views.

FIGURE 2 shows the head 14 which includes a generally cylindrical portion 30 with threads 32 on the outside of its lower end for threading into the top section of the well casing. The side outlet 16 is preferably located about midway between the upper and lower ends of the cylindrical portion 30.

At the upper end of the cylindrical portion 30 there is a rim providing a shoulder 34 inside the head 14 and this shoulder rovides an abutment surface for holding a top plate 42 in the head. Under this top plate 42 there are a plurality of packing seals 43, 44, 45 and 46 in the head. Below the packing seals there is a bottom plate 48 which fits into the cylindrical portion 30 and the seals 43-46 between the plates 42 and 48 to serve as a stufiing box around the tubing string 24 and the drilling or swabbing line 26 to prevent escape of gas through the upper end of the head 14.

In order to construct the head 14 so that it can be placed in the top of the well casing and around the drilling or swabbing line without disturbing them, the head 14 is made in two parts which divide along a plane 50 (FIG- URE 3) which coincides with the diameters of the tubing string 24 and the drilling or swabbing line 26. In order to obtain proper alignment of the two sections of the head 14, there are tapered pins 51 projecting from one section and which fit into complementary openings in the other sec'ion.

Not only the cylindrical portion 30 is so divided but also the top plate 42 and the lower plate 48. The packing seals 42-46 are constructed so that they can be placed around the tubing and drilling or swabbing lines and in contact with the inside surface of the cylindrical portion 30 of the head and this can be done in various ways depending upon thetype of packing seals that are used. In FIGURE 2 the packing seals 43-46 are made with split portions at different locations and by having a plurality of packing seals at different locations lengthwise of the head 14, the splits or discontinuities in the packing seals come at different places so that there is no location where there is not a solid section of packing at one place or another along the assembly packing seals 43-46.

After assembly of the various parts of the head 14 around the tubing and cable strings, the assembled parts are held together by clamps 54 which fit tightly around the upper and lower parts of the head 14. The clamps 54 are shown provided with a fastening in the form of clamping bolts 56.

FIGURE 4 shows a modified construction for the head. In this modified construction a head 14 is provided with an outlet 16' and has threads 32 at its lower end. The head has a cylindrical portion 30' with a shoulder 34'.

A cove-r generally shown at 38 includes a lower plate 42' that rests on the shoulder 34', and an upper plate 60 which serves as a stuffing box gland. Packing sea-ls, for example, 43 and 46', are clamped between the lower plate 42 and the upper plate 60 and this upper plate 60 is attached to the head 14' by bolts 61 which extend through openings in the top plate 60. There are nuts 62 threaded on the upper ends of the bolts 61 for clamping the top plate 60 tightly against the packing seals 43' and 46' to control the pressure of the packing seals against the inside of the cylindrical portion 30' and against the tubing string 24 and the drilling or swabbing line 26.

The lower plate 42 and the top plate 60 are made in two parts with a split along a plane 50 in order to fit around the tubing string and the drilling or swabbing line as in the case of the construction described in FIG- URE 2; but the cylindrical portion 30' is of different construction and has a longitudinal slot 66 (see FIGURE extending for the full height of the cylindrical portion 30'. This slot 66 is wide enough to pass the drilling or swabbing line 26, and will now be described in more detail.

The side wall of the cylindrical portion 30, on both sides of the slot 66, is constructed with a radially extending flange. The flange on the lefthand side of the slot 66 is indicated by the reference character 68 and the flange on the righthand side of the slot 66 is indicated by the reference character 69. These flanges extend from the top of the cylindrical portion 30' to a location 72 which is somewhat above the threads 32. Below the location 72 the cylindrical portion 30 does not have flanges on opposite sides of the slot 66 since these would interfere with the continuity of the threads 32'.

A filler 74 fits into the slot 66 throughout the entire length of the slot and closes the slot after the head 14' has been placed around the drilling and swabbing line 26 and around the tubing string if the latter is also an obstruction. This filler 74 extends out for the full radial extent of the flanges 68 and 69 along the part of the head where there are flanges 68 and 69, but not below the location 72. The filler 75 below the location 72 is flush with the circumference of the cylindrical portion 30' and is threaded in the same way as the rest of the cylindrical portion for screwing it to the upper end of a well casing.

In order to insure alignment of the threads 32' on the filler 66 and on the other portions of the head 14' at opposite sides of the slot 66, there is a tapered pin 78 which fits into complementary openings through the flange 68, filler 74 and flange 69 so as to always bring these parts into the same longitudinal alignment with one another.

This also aligns openings 81, 82, and 83 which extend through the flanges 68 and 69 and through the filler 74 for receiving bolts 85 which clamp the flanges 68 and 69 against the opposite sides of the filler 74 after the parts have been brought into alignment by the pin 78.

The connection of the bolts 61 to the outside of the cylindrical portion 30 is by means of lugs 88 welded to the sides of the head 14 and by cross pieces 90 welded to the bolts 61 below the lugs 88. This provides a secure connection between the bolts 61 and the outside of the head 14' and eliminates possibility of the bolts becoming lost since they are permanently attached to the head; but other expedients can be used for holding the bolts 61 such as a conventional flange around the outside of the head, but with the same slot 66 as in the cylindrical portion 30.

The preferred embodiments of the invention have been illustrated and described, but changes and modifications can be made and some features can be used in different combinations without departing from the invention as defined in the claims.

We claim:

1. A casing packing head including, a cylindrical threaded portion for connection to the upper end of a casing of a well, a cover having an opening for a tubing string that extends down into the casing from above the head, the cover being formed in two parts and having its line of division across said opening whereby the cover can be assembled over the tubing string, means for holding the parts of the cover tightly together, and the cover also including packing means, said packing means comprising a plurality of split packing seals arranged substantially coaxially in said head and effecting a gas tight seal with the side walls of said head to prevent the escape of gas from said well.

2. The casing packing head described in claim 1, said cover having a second opening on the line of division for a cable line.

3. The casing packing head described in claim 2, the cylindrical portion of the head extending to the top of the head and the cover extending into the upper end of the cylindrical portion of the head, and a branch outlet in one side of the head above the casing coupling and below the cover for the release of gas from the annular space within the well.

4. The casing packing head described in claim 3, the packing means being between the part of the cover that extends into the upper end of the head and a confronting area of the inside surface of the cylindrical portion of the head.

5. A casing packing head including a cylindrical threaded portion for connection to the upper end of a casing of a Well, a cover having an opening for a tubing string that extends down into the casing from above head, the cover being formed in two parts and having its line of division across said opening whereby the cover can be assembed over the tubing string, means for holding the parts of the cover tightly together, and the cover also including packing means in position to prevent gas under pressure in the well from escaping between the cylindrical portion of the head and the cover, said cover having a second opening on the line of division for a cable, the cylindrical portion of the head extending to the top of the head and the cover extending into the upper end of the cylindrical portion of the head, and a branch outlet in one side of the head for the release of gas from the annular space Within the well, the packing means being between the part of the cover that extends into the upper end of the head and a confronting area of the inside surface of the cylindrical portion of the head, said packing means including a plurality of split seal means, the seal means immediately adjacent said cover having solid portions extending across the line of division of the cover.

6. The casing packing head described in claim 5, said packing seal means also sealing between the cover and the tubing string and cable.

7. A casing packing head including a cylindrical threaded portion for connection to the upper end of a casing of a well, a cover having an opening for a tubing string that extends down into the casing from above the head, the cover being formed in two parts and having its line of division across said opening whereby the cover can be assembled over the tubing string, means for holding the parts of the cover tightly together, and the cover also including packing means in position to prevent gas under pressure in the well from escaping between the cylindrical portion of the head and the cover, said cover having a second opening on the line of division fora cable, said cover including a stuffing box gland plate, and a lower plate which seats on an abutment surface within the cylindrical portion of the head, the gland plate clamping the packing means against the lower plate.

8. The casing packing head described in claim 7, said planed plate having a portion that extends across the top of the head radially beyond a portion of the head located below the plate, and fastening means around said portion of the head located below the plate and at angularly spaced locations around the head for holding the plate on the head, said fastening means being adjustable to change the pressure on the packing means.

9. The casing packing head described in claim 8, said fastening means being a circle of bolts with the bolts connected to the outside of the head by welding and with threaded upper ends of the bolts extending above the top of the head and through and beyond openings through the plate.

10. A casing packing head including a cylindrical threaded portion for connection to the upper end of a casing of a well, a cover having an opening for a tubing string that extends down into the casing from above the head, the cover being formed in two parts and having its line of division across said opening whereby the cover can be assembled over the tubing string, means for holding the parts of the cover tightly together, and the cover also including packing means in position to prevent gas under pressure in the well from escaping between the cylindrical portion of the head and the cover, said cover having a second opening on the line of division for a cable, said head having a longitudinal slot extending for the full length thereof and Wide enough to pass over a tubing string and a cable with which the head is intended to be used, and means for closing the slot after the head and cover are placed around the tubing string and cable.

11. The casing packing head described in claim 10, further including means for aligning the opposite sides of the slot to close the slot with the opposite sides in a predetermined relation to one another.

12. The casing packing head described in claim 11, the lower end of the head being threaded for screwing into a well casing, and the aligning means being in position to align threads on opposite sides of the slot.

13. The casing packing head described in claim 10, further including a filler piece that fills the slot, radially extending flanges along opposite longitudinal edges of the slot, and fastenings that extend through the flanges and filler to hold the filler in the slot.

14. The casing packing head described in claim 13, further including a tapered pin that extends through openings in the flanges and filler to align the fastening openings.

15. The casing packing head described in claim 14, further including threads on the lower portion of the head for connecting the head with a well casing, the threads extending across the filler, and said filler, at the threaded portion of the head, having its outside surface flush with the adjacent outside surface of the head on both sides of the slot.

16. The casing packing head described in claim 2, the cable line being for swabbing.

17. The casing packing head described in claim 2, the cable line being for drilling.

References Cited UNITED STATES PATENTS 836,065 11/1906 Coates l6693 X 858,321 6/1907 Auchu 166-93 1,258,273 3/1918 Titus et al 16693 X 1,708,645 4/1929 Wright 166-93 X 2,153,852 4/1939 Tschappat 16688 X 2,168,591 8/1939 Tschappat 16688 X JAMES A. LEPPINK, Primary Examiner,

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