US2211122A - Tubing head and hanger - Google Patents

Description

Aug. 13, 1940. J. H. HOWARD 2,211,122

TUBING HEAD AND HANGER Filed March 10, 1938 v (Q f3 4 2 James H. Howard. i INVENTOR.

Patented Aug. 13, 1940 PATENT OFFICE TUBING HEAD AND HANGER James H. Howard, Houston, Tex., assignor to J. H. McEvoy & Company, Houston, Tex., a

corporation of Texas Application March 10,

4 Claims.

This invention relates to improvements in well head equipment and particularly to improved means for sealing the space about a well tubing and suspending the well tubing.

The general object of this invention is to provide a sealing device which can be renewed whenever desired and to provide a means in connection therewith for suspending tubing therein without interfering with the renewal of the sealing device.

In the successful completion and handling of deep high pressure oil and gas wellsit is necessary to provide equipment whereby tubing, through which a well is to be washed, may be placed within the well, and the space about the tubing sealed off so that the well may be washed without danger of blowing out. Where such tubing is also to be used in flowing the well after it is brought into production, it is further necesin a desired position.

The present invention relates to such an apparatus in which the suspension means for the tubing is located above the seal about the tubing 25 so that the suspension device may be applied to the tubing or released at will.

Inasmuch as the tubing employed is 'not finished on its outer surface, movement of this tubing through the seal above mentioned frequently results in damage to the seal to such an extent as to make it unsuitable as a permanent seal during the production of the well. Heretofore, when this condition prevailed, it was necessary to pump heavy fluid such as mud or weight material into the well in a sufflcient amount to hold in the well pressure so that the well could be opened and the packing replaced. Such practice, however, in addition to requiring a good deal of time is rather dangerous in that it can never be known with certainty that sufllcient weight material has been added to hold the pressure in, and if too much weight material is placed in the well the well may be permanently killed or damaged to such an extent that reworking will be necessary.

To avoid killing a well forthe purpose of replacing the seal about the tubing, and to eliminate the other hazards and undesirable results prevalent'in previous well completion methods 50 and apparatus is one of the primary objects of this invention.

In addition to the foregoing, in those forms of apparatus where the tubing suspension means was placed above the seal about the tubing, it was necessary in order to renew the seal in event sary to provide means for suspending the tubing 1938, Serial No. 195,023 (01'. 166-14) a leak showed up to have the drilling equipment in place over the well. If the leak did not appear until after the well had been completed, that is,

if the seal about the tubing retained its efl'ectiveness sufficiently to prevent a leak until the I; well had been completed and the drilling equipment removed, it would then be necessary when the leak did appear not only to kill the well, as I above described, but also to move the extremely heavy and expensive drilling equipment back onto the well and set it up in order to lift the heavy string of tubing while the suspending means was removed for the purpose of obtaining access to the sealing means in renewing the same. In this connection it is to be noted that not only is the matter of replacing the drilling equipment expensive because of labor involved but also because of the fact that the expense of maintaining the drilling equipment for deep wells varies from $300.00 per day upward and considerable time is consumed in putting the equipment in place and removing it again after the seal has been renewed.

Also, during the replacing of the drilling equipment as just mentioned there is involved a great hazard due to the likelihood of damaging the christmas tree and other control equipment at the top of the well which is during that time under heavy pressure. 0f no mean consequence is the fire hazard attendant upon erecting the drilling equipment while the seal-about the tubing is leaking.

It is, therefore, another object of this invention to make it possible to renew the seal about the tubing of a producing oil or gas well without necessity for providing and erecting equipment for lifting the tubing which is positioned within the well.

Itis a further object of this invention to provide a means for sealing about a tubing in a well, a portion of which sealing means can be removed and replaced without disturbing the efi'ectiveness of the remainder thereof.

Another object of this invention is to provide a sealing means for sealing about a tubing in a well, a portion of which sealing means may be removed and replaced without disturbing the remainder thereof, and in addition to provide a means for draining off whatever leakage may occur through that portion of the sealing means that is not so removed.

Another object of this invention is to provide a means for sealing about a tubing in a well and for supporting the tubing from a point above the sealing means in such a manner that a portion of the sealing means may be removed and replaced during the time the tubing is suspended from the tubing suspending means.

Another object of this invention is to provide such a device in which the tubing may be prevented from upward as well as downward movement.

Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawing, it being understood 'that the same are by way of example and illustration only and not by way of limitation. This invention is to be limited only by the prior art and by the terms of the appended claims.

In the drawing:

Fig. 1 is a vertical cross section of an apparatus constructed in accordance with this invention.

Fig. 2 is a horizontal cross section of the apparatus shown in Fig. 1 taken along the line 2-2 of Fig. 1.

The numeral designates the customary well head body adapted to be secured by means of threads 2 or the like to the upper end of a well casing and having lateral outlets 3 and intermediate its upper and lower ends.

Within the upper portion of this well head body there is provided a tapered surface 5 adapted to receive the lower end 6 of the body of the sealing and suspending means to which,

hold down cap being in turn secured by a threaded connection II to the upper end of the well head body I. It will thus be seen that the body of the sealing device will be held in sealed engagement with the upper end of the well head body I by means of the hold down cap III. This hold-down cap may be provided with ears I2 or the like for use in handling the same.

The body of the sealing device which is indicated by the numeral I3 is provided with an opening therethrough adapted to receive a tubing It, and this opening is counter-bored from both its upper and its lower ends as indicated at I5 and I6, respectively, for the purpose of receiving packing to form a seal between the body 3 and the tubing I l. The lower counter-bored portion of this body has disposed therein a solid ring II against which is disposed suitable packing I2 which in this instance is made up of V-shaped rings of packing material of such a nature that pressure from within the well will tend to cause expansion thereof so as to make this packing in a measure self-sealing. This packing 8 is supported in its position within the counter-bore I5 by means of a gland nut I9 threaded into the interior of the body I3.

The upper counter-bore I6 is likewise provided with a solid abutment ring 2|] adapted to receive packing 2| of a nature similar to that just referred to and upon this packing there is preferably positioned additional-packing 22 of a substantially homogeneous nature. This packing 22 is expansible and is expanded into a sealed position by means of a split packing gland 23 urged downwardly against the said packing by cap screws 24 which are threaded into oppositely extending flanges 25 on the body l3. The body I3- above the flanges 25 is provided with lateral openings 25 of such a nature that the sections of the split gland 24 may be inserted thereinto, one at a time, and then moved together to form the complete gland. It will be understood that this gland is made in two parts for ease in assembling but that under certain circumstances it could be made of one integral part and inserted into the body I3 in one piece.

The ears or laterally extending portions 21 of this gland are formed with suitable openings for receiving the cap screws 24 previously mentioned, and these ears overlie the flanges 25 on the body member.

The upper end of the body member I3 is threaded as at 28 or provided with other means for receiving an internally tapered bowl member 29 adapted to receive slips 30 which in turn engage the tubing I4 to support the same. In order to hold these slips down and cause them to grip the tubing even when the tubing tends to move upwardly, there is provided an annular ring 3| adapted to engage the upper ends of these slips and to be held thereagainst by cap screws or the like 32. These cap screws pass through the ring 3| and threadedly engage the bowl 29 to hold the slips 30 down and in engagement with the tubing I4. The slip bowl 29 may be provided with laterally extending lugs 33 for ease in handling.

The body I3 is tapped at 34 intermediate the ends of the counter-bores I5 and I6 for the purpose of receiving a drill pipe or bleeder pipe 35 controlled by a suitable valve 36.

In operation, the device is assembled as illustrated in Fig. 1 and when the well is ready for flowing the tubing is suspended by means of the slips 30. 7

If due to the activities which have preceded the completion of the well the packing I8, 2| or 22 has become defective, or if it is suspected that defects may exist which may later result in leaks, the valve 36 may be opened so as to relieve any pressure which may have leaked past the packing I8. With this pressure relieved, even though there may be some leakage past the packing I8 the cap screws 24 may be removed and the gland 23 raised after which the packing 22 and if necessary the packing 2| also may be removed and replaced with new packing. The well pressure during this time will be held by the packing I8 even though a slight leakage may be permitted, and when the packing 2| and 22 is in place, this leakage will be permitted to escape through the valve 36. With the gland 23 replaced and secured in position valve 36 may then be closed and the seal about the tubing having been renewed there will be no danger of leakage around the tubing.

It is to be particularly noted that the lower packing l8 and the lower portion 2| of the packing in the upper counter-bore is of a nature which will be expanded into sealed engagement by the pressure from within the well. Such packing, however, is of ordinarily a fibrous heat resisting composition so that it will better withstand the temperatures encountered.- Because of this fibrous nature this packing will not form a perfect seal but under conditions of high gas pressure there will be some seepage. For this reason, there is included in the upper counter-bore a section of homogeneous packing of oil resistant rubber or material of like nature. By this means a perfect seal is provided and seepage is positively prevented.

It will be readily seen that by the foregoing 75 there has been provided an apparatus by which it is made possible to suspend a tubing from a point above the top of a well, and while the tub-.

ing is suspended to remove and replace a portion of the seal about the tubing so as to prevent seepage therethrough. It will be seen that in carrying out this operation with the present equipment there is no necessity for killing a well by introducing weight material, and further that there is no need for expensive drilling equipment such as would be necessary to raise and handle the tubing if it were necessary to remove the tubing suspension means before renewing the tubing seal. Means has also been provided for relieving any pressure which might exist on that portion of the tubing seal to be removed and renewed, and for taking care of any leakage which might occur past that portion of the seal not removed during the removal and replacement of the other portion of the seal.

Having described my invention, I claim:

1. A combination tubing support and seal comprising a member adapted to be sealed to a well head body, a plurality of sealing means carried by said member for forming a seal between said member and a tubing passing therethrough, securing means accessible from outside said member when the same is mounted on a well head body for releasably securing the upper of said sealing means in place and movable to permit replacement of said sealing means, tubing support means above said sealing means for supporting tubing passing therethrough, and means for supporting said tubing support means on said member independently of said sealing means, the lower of said sealing means including a comparatively less homogeneous and more heat resisting sealing material, and the upper of said sealing means including a comparatively more homogeneous and less heat resisting sealing material.

2. A combination tub-ing support and seal comprising a member adapted to be sealed to a well head body, a plurality of sealing means carried by said member for forming a seal between said member and a tubing passing therethrough, securing means removable from outside said member'when the same is mounted on a well head body for releasably securing the upper of said sealing means in place and movable to permit replacement of said sealing means, tubing support means above said sealing means for supporting tubing passing therethrough, means for supporting said tubing support means on said member independently of said sealing means, and means for retaining the lower of said sealing means in sealed position, said last mentioned means being accessible only from within said member when said member is not mounted on a well head body the upper of said sealingmeans being replaceable while a tubing is supported therein by said supporting means.

3. A combination tubing support and seal comprising a member adapted to be sealed into a well head body, and having a stufiing box formed therein, opposed packings in said stufling box adapted to form a seal about a tubing passing therethrough, means accessible only from within said member for securing one of said packings within said stufling box and means accessible from outside said member for securing the other of said packings in said stufling box, valve means for releasing the pressure between said packings, a slip bowl supported an appreciable distance above said stufling box and spaced therefrom, and means for supporting said slip bowl from said member without obstructing access to the said means for retaining said second packing.

4. A combination tubing support and seal comprising a member adapted to be sealed to a well head body, and having a packing receptacle formed therein, opposed packings in said receptacle adapted to form a seal about a tubing passing therethrough, means accessible only from that portion of said member which is in communication with the interior of the well head body during use for securing one of said packings within said packing receptacle, and means accessible from outside of said member for securing the other of said packings in said packing receptacle, tubing holding means supported an appreciable distance above said packing receptacle and spaced therefrom, and means for supporting said tubing holding means from said member without obstr cting access to said means for retaining said sec nd packing while a tubing is supported therein by said supporting means.

JAMES H. HOWARD.

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