US1827287A - Casing head - Google Patents

Description

Oct. 13, 1931. I E. umm 1,827,287

CASING HEAD Filed Jan. 6, 1930 I ZSheets-Shea 2 I dwaraf 1T Guidinge be a tight seal between M m is. 1931 1,827,287

OF BARTLESVILLE, OKLAHOMA, ASSIGNbR TO PHILLIPS OF BARTLESVILLE, OKLAHOMA, A CORPORATION OF DELA- nnwann r. summers,

PETROLEUM COMPANY, WARE c emo HEAD Application filed January 6, eso. Serial, No. 418,863.

screws, etc., at the casing Another object is to furnish a casing head having a ground surface to contact with the corresponding surface of a tubing hanger, and also provided with means for protecting said ground surface to prevent mutilation of the same while the tubing is being fed into the casin This invention relates to improvements in well equipment, and more especially to improvements in oil wells of the type employing a casing and tubing. To facilitate an understanding of the present invention, it may be well at the begmning, to explain the use of the two different terms casing and tubing. An 011 well 1s nearly always completed for production with a string of steel pipe extending from the surface of the ground to the top of-the oil sand, or near it. This pipe is called the well casing. When the well is to use a gas lift, anotherstring of smaller pipe, called tubing, is inserted through the casing, the lower end of this tubing being placed wherever the well functions the best from the standpoint of oil production and quantity of gas required.

In some wells, the gas is admitted through the tubing and passes out at the bottom through the oil, risingto the top of the well through the space between the tubing and the casing. In other set-ups, the procedure is reversed,'the gas being injected into the well in the space between the casing and tubing, mixing at the bottom withjthe 011, and the mixture rising to the top through the tubing.- The-latter inthodiof hook-upis the one nearlfy always used in fields where the quality 0 the oil is such that there is a ten-- dency toward deposition of paraflin on the walls of the flow column. In a set-up of this character, it is; not only necessa that there with other objects 1n v1ew which will appear as the description proceeds, the invention consists in the novel features hereinafter described in detail, illustrated in. the accompanying drawings, and more particularly pointed out in the appended claims.

Referrmg to the drawings,

improved casing head and tubing hanger, and a portion of the well tubing.

Fig. 2 is a plan view of the casing head partly in horizontal -section,'the section being taken on the line 2'-2 of Fig. 3.

Fig. 3 is an elevation of the head, partly 1n vertical section, the section being taken on line 3-3 of Fig. 3. v

Fig. 4 is a plan view of my novel tubing hanger.- I

. iFig. 5 is an elevationofthe saine,"partly in vertical section, on the line 5-5 of Fig. 4:.

By reference to the drawings, seen that an ordinary well casing 6 is provided with internal threads that are engaged by external threads on my casin head 8 thetubmg and the casing. at the well, mouth, but the sealingmeans should be simple, effective, and should lend itself. toa quick andbjasy'change in amount of tubing mythe'wel-lt, i. -l The-primary object of. the present inven'- tion .isto' pro 'de such a sealin means of a, novel type, 'and-one-which will relatively inexpensive to. manufacture.-

Another object is to furnish such a sealing means, preferably comprising only two parts, one a packing head, and the other, a tubing piece of metal, such as steel, and it is of tubuar form, the lowerportion,beingprovided with the threads downwardly flared or frusto-conical surface 9 on its interior. While the surface 9 may be of any suitable inclination, I prefer to taper tively guides the tubing, (hereinafter referred to), as the latter is raised in, or withdrawn from the casing. v

The upper end of the surface 9 merges into a cylindrical surface 10, which extends upwardly on the inside of the head to an upanger.

A still further object is to provide a com.- bined casing head and tubing hanger, which will contact by means of ground surfaces, and

which will eliminate the use of packing, bolts,

head of the well.

With die foregoing'objects outlined and the section being taken This head is preferably formed'o a single the same about six and one-quarter inches per foot, as I have found that such a surface eflec- Fig. 1 is a diametrical vertical sectional new of the upper end of 'a well casing, my

it may be 7 on its exterior, and a taper of about ten inches per foot. This surface 11 acts as a protector for a frusto-conical ground sealing surface 12, which is arranged above the surface 11, and preferably has a slightly different inclination from the latter.

surface. For example, the flared surface 12, may have a taper of about fourteen inches per foot.

It is highly essential that the surface 12 be protected from scarring or mutilation, and this is insured, not alone by the guide surface 11, but by an annular groove or channel 13, which is arranged within the head, and is located between the surfaces 11 and 12. As a further precaution, an annular recess or rabbet 14 is located in the head between the upper end of the surface 12 and. the horizontal top surface 15 of the head, to prevent any elevating means placed on the surface 15 from contacting with or scarring the upper end of the surface 12.

The head terminates at its upper end in an annular flange 16, so as to provide an enlargement on which the tubing elevator may rest, and below this flange, the head has the usual lateral screw threaded openings 17 to be at tached to pipes that lead to or from the head.

This novel head cooperates with the tubing hanger 18, which is shown in detail in Figs. 4 and 5, and this hanger is also preferably made of a single piece of steel, and is provided with a centrally disposed vertical bore, having internal screw threads 19 and 20. in order that the hanger may be interposed between two sections 21 and 22 of the tubing string and function as a joint in such string. To allow the hanger to be readily operated by a wrench, the threads 19 are formed in an upwardly extending boss'or nipple 23, having angularly arranged surfaces 24 on its exterior.-

Thelower portion of the hanger is provided with an external frusto-conical ground surface 25, which is tapered to conform with the surface 12, and as the surfaces 12 and 25 are ground and snugly interfit when the hanger 18 is resting on the head 8. it will be understood that the weight of the tubing string will thus provide a sealed joint which will prevent the exit of gas.

In operation, the weight of the tubing, when resting on the tapered surface 12, gives a perfectly tight seal. preventing loss of gas, but when it is decided to take the tubing out of the well, or run in additional joints, it is only necessary to lift the string. of tubing with the ordinary elevator and tubing blocks, whereupon the tapered tubing coupling 18 rises from the tapered seat 12, on the head, and can be lifted up high enough to take the hanger 18 out of the string of tubing. After this is done, additional joints of tubaaaaeev ing may be run through the head, the couplings of such tubing passing freely through the bore of the hea As the tubing is moved into the well, the couplings have a tendency to strike the tapered surface 12, which would, in time, prevent the proper seating of the head 18, and result in a leaky joint. To prevent this, the head has been provided. with the tapered guide surface 11 for the purpose of guiding the tubing to facilitate the passing of the couplings thereof through the head. The recess 14, during such operation, prevents any possibility of mutilation of the surface 12 by the tubing elevators, which rest on the top of the head during the process of running tubing in, or out of the well. By taking the two precautions of shaping thelower surface.

11 as a guide for the tubing couplings, and the recess 14 at the upper end of the surface 12 to prevent mutilation, the latter surface, which ,is the sealing ring, is practically assured of being kept free from any damage.

So far as I am aware, there is no head made that will serve this purpose, in as simple a way, and with as few parts as the head which I have devised. The ordinary head used, consists generally of a casing head, a tubing support, and numerous glands, packing rings, slips, bolts, etc. Most of such heads must be taken off the casing in order to get additional joints of tubing in or out of the hole. Mv

improved head permits the free movement of the tubing with a minimum number of parts to be handled, and is very effective in its purose. P Some effor s have been made to provide heads capable of producing the same results as mine, but mv head differs from them in at least three different details. In the first place, the prior art heads have at their lower ends, internal, instead of external threads. An external thread, such as shown at 7 in my drawings, is much cheaper to cut in the shop, and from that standpoint, more desirable.

In the second place, each of the prior proposals, while suggesting the use of a tapered surface, shows only one tapered surface in the head for the reception of the tubing collar, and also has packing of some sort. In one instance, it is proposed to wrap the tapered tubing collar with a laver of ead or similar sheet packing. and rely on the seal of this packing to hold the pressure. In another case, it is suggested to cut grooves in the tapered tubing collar or hanger in which are to be placed square hydraulic packing. thusrelying on the contact of this packing with the tapered seat in the head for cutting off the pressure. In my head, I rely solely on the fit secured by proper machining of both the tapered seat and the tapered collar for the pressure shut-off. In practice, I have demonstrated that if these tapered surfaces are properly machined, and then ground to proposals differ from mine,

, occur by this .a fit, no difficulty is had in making a tight joint if the surfaces are perfectly clean when the tubing string is set down.

A third particular way in which the prior is that in the prior structures, no provision is made for protection of the tapered seat in .the head, against abrasion from collars on the tubing string,

while being run through the head. It is obvious, as the tubing string is'run into the casing, joint after joint being screwed into the top collar, and the entire string being lowered into the hole through the head, that the coupling collars will have a tendency to strike on one side of the circular opening of the head. If these collars strike the surface 12, some mutilation is to be expected, thereby preventing a perfect contact between the surfaces 12 and 25. In my head, I take care of this 'by providing the guide surface 11 on which the collars, as they pass into the hole, may strike-and be deflectedtowards the center of the hole, making it impossible for the collar to hang on any part of the head as it passes through, and whatever mutilation may striking, is on this guide surface 11. When the hanger 18 isset down, in order to effect the shut-ofl:', the tapered sur face 25 on the tubing collar does not rest in contact with any part of the surface 11, but contacts only with the surface 12, which has been arranged purposely for this contact. As stated heretofore, the top edge of the surface 12 is turned off for about half an inch below the flat top 15 of the head, and when elevators which support the tubing strings by contact under a tubing collar, rest on the flat top of the head 8, it is practically impossible for any mutilation to occur on the upper tapered surface 12. It will therefore be seen that the surface 11 and the groove 14 insure the protection of the surface 12, so that the latte] may always-properly cooperate with the surface 25 to make a perfect seal without the use of packing, bolts or the like.

Another advantage of my head over any of those on the market, resides in the extreme simplicity of construction and assemblv, due to the fact that it consists of only two parts. Any head which involves the use of such parts, together with packing, bolts, auxiliary flanges, etc., adds to the expense and diflicultv of equipping a well, ofttimes delaying work or making the job more or less incomplete. These heads are usually upper portion of its bore,

construction, operation and advantagesof my invention may be readily understood, and I am aware that changes may be made in the details disclosed, without departing from the spirit of the invention, as expressed in'the claims. 1

What I claim and desire to secure by Letters Patent is: v

1. A casing head comprising a metal tubular member having in the upper portion 0 its bore, an upwardly flaring ground contact surface, the bore being provided with an annular recess-spacing the upper end of said surface from the top of the head, an upwardly flared guide surface arranged below said contact surface, the bore having an annular groove arranged between the contact surface and the guide surface.

2. In combination, a casing head comprising a metal tubular member having in the an upwardly flaring .ound-contact surface, the bore being provided with an annular recess spacing the upper end of said surface from the top of the head, an upwardly flared guide surface arranged below said contact surface, the having an annular groove arranged between the 0011 act surface and the guide surface, and a tubing hanger provided with an external ground surface conforming to and contacting with the ground surface of the head.

In testimony whereof, I affix my signature.

EDWARD F. GUIDINGER.

installed on wells which have a'tendency to real advantage to use my improved head which does not require any unusual effort to finish the job. i

From the foregoing it is believed that the

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