US1950267A - Cold shrunk-in valve seat - Google Patents

Description

March 6, 1934. i 4 PR|E 1,950,267

COLD SHRUNK-IN VALVE SEAT Filed April 27, 1931 amt idem/rake,

Patented Mar. 6, 1934 1,950,267 com SHRUNK-IN VALVE SEAT Frederick Price, Stroud, Okla assignmto Price- Trawick, Inc., Stroud, Oklahoma 0kla., a corporation of Application April 2'7, 1931, Serial No. 533,321

2 Claims.

This invention relates to a removable, or pressed in, or cold-shrunk in valve seat, and to the combination of said valve seat with a receiving port forming part of a suitable body and is more particularly designed and intended for use in combination with a tubing collar such as shown in my Patent No. 1,793,193, granted February 17, 1931, and will usually be used in oil wells and subject to all of the conditions obtaining in all portions of such wells.

The liquid in practically all oil wells has present in it a number of different minerals, salt water, corroding agents, parafiine, and base settlements, these ingredients being present in varying degrees in difierent wells and varying greatly in degree often as between two wells from widely separated oil fields or areas.

Such minerals and corroding agents of course act upon the metal of the tubing and particularly the body and faces of all working or cooperating parts, such as the valve assemblage shown in my said Patent No. 1,793,193, and the seat cooperating with said valve, and even though said seat may be made of an inner corrosive metal, such as malleable metal, the sand and gravel carried in suspension by the fluid as well as scale, will in time out into, wear away, and deface and render defective the faces and in fact the body portion of the valve seat.

The present invention has in mind particularly to avoid the above objections and defects which are to be found in a construction having the valve seat integral with the body member or permanently associated therewith so as not to be removable but provide a construction whereby the valve seat may be pressed into place in its receiving port under great pressure by what is generally referred to as a cold shrinking process, so that in operation it will be for all practical purposes operatively integral with the body in which it is positioned, and yet may be removed when it becomes so worn or defaced as to be operatively defective. A further object or purpose of the present invention is to provide a construction of both cooperating elements, that is the body which receives the seat and the seat so combining the two that the valve seat may be inserted into position from either side of the wall of the body in which it is positioned and similarly may be removed by pressure directed to either side of the said wall, in other words, whereby the seat may be forced in either direction endwise 0! its receiving bore either in insert-' ing and positioning the seat in operative position or in removing the seat preparatory to the insertion of another seat by way of substitution therefor.

In the practice of my invention, I form the collar or body which receives the seat with a radial bore having a smooth cylindrical inner M wall of the same diameter from end to end and provide a seat having a cylindrical, outer, peripheral face and being of an external diameter slightly in excess of the internal diameter of the said bore. In practice I prefer to use a seat havthe pressure or force necessary to cause any I movement of said seat endwise of its receiving bore will want to be always such as to be greatly in excess of any pressure that will have to be resisted by said seat in cooperation with its valve element under any operative conditions in any well in which it may be located.

In the accompanying drawing:

Fig. 1 represents a central vertical cross section through a fragmentary portion of a well casing disposed about a well tubing in which a collar embodying my invention is inserted; the valve member cooperating with the valve seat being illustrated in elevation;

Fig. 2, a view similar to Fig. 1, but omitting the valve assemblage;

- Fig. 3, a view on a greatly enlarged scale and taken in the same plane as Figs. 1 and 2 and showing a fragmentary portion of the body portion about the valve seat receiving'port and the valve seat adjacent thereto, with the valve seat in its normal or pre-shrunk in condition, the

slight excess diameter of the valve seat being exaggerated and being indicated by the dotted lines extended from the diametrically opposite portions of said port;

Fig. 4, a perspective view of the valve seat by itself; and

Fig. 5, a fragmentary detail sectional view taken on the line 5-5 of Fig. 2 and looking in the direction of the arrows.

Referring now in detail to the drawing, A designates the usual well casing; D, a collar having oppositely presented internally screw-threaded ends respectively receiving the externally screw-threaded ends of pipe sections B and C of the usual well tubing; E, a vertical slot formed in the collar D to receive the leaf spring G to which is connected the double-valve unit F by means of a free or wobbling or universal joint or 1 connection, said spring being mounted in said groove E by means of a screw H, the outer portions of the walls of said slot extending radially outward beyond the-extreme movement of all vof the portions of said screw H, spring G, and

valve unit F.

All of the foregoing parts described in the immediately preceding paragraph may be and preferably will be as illustrated and described in my said U. S. Letters Patent No. 1,793,193 and in particular the double valve unit and its suspending or positioning spring, whether they be of the form exactly as illustrated in said Patent No. 1,793,193 or of some other form, will be so constructed, mounted and related to each other and to the cooperating valve seat 2 that, as assembled and in operative condition, the valve may have a free wobbling motion with relation to its seat whereby it may shift its position under the influence of pressure as may be required by scale or to the obstructions on some part of one or the other or both of the operative seat faces of the valve seat to firmly and completely seat itself to close communication between the interiors of said tubing and easing through said valve seat, all as mentioned in said Patent No. 1,793,193.

The body D is formed with a reinforced or thickened portion d surrounding the cylindrical radially extending port 1 and embracing or including the walls defining the slot E, said thickened portion resulting in increasing the strength of the body adjacent the port 1 and increasing the length of said port 1 in a radial direction. In practice I prefer to make the port 1 one-inch in diameter and of course of uniform diameter from end to end, though if preferred the extreme end portions of said port 1 may be flared, or coned or outwardly tapered to facilitate the insertion of the seat 2.

With a port one-inch in diameter, the seat 2 should be one and two one-thousandths (1 2/ 1000) of an inch in external diameter or approximately of a diameter two one-thousandths (2/1000) of an inch in excess of the internal diameter of the port 1 where said port 1 is of an internal diameter of substantially one-inch; the body or collar D being of malleable cast iron and theseat 2 being of Monel metal. Of course where the bore 1 is of much greater internal diameter the ratio between the intemal diameter of said bore and the external diameter of said seat 2 should be maintained or the excess size of the seat 2 might even be increased with good effect. Also where some materials other than malleable cast iron and Monel metal are employed it may be necessary to either increase or to slightly decrease the difference between the internal diameter of said port 1 and the external diameter of said seat 2, depending upon the properties of the materials employed. However, I prefer to use the malleable cast iron for the body D and Monel metal for the seat 2, I prefer to use a seat 2 of Monel metal to be inserted in the port 1 of said malleable cast iron body D, and in practice I have found that for the average well and as the most suitable or universal size a port one-inch in internal diameter receiving a. seat one and two-one-thousandths (1 2/1000) of an inch in external diameter gives very satisfactory results and has proven out as highly efflcient, the frictional bond "1, the most convenient and satisfactory means.

being a large powerful press such as is now used in a great number of different metal working arts. In inserting the seat 2 the stroke of the press or plunger will be so calculated and regulated as to press the seat 2 radially inward axially of the port 1 to a standard distance'or uniform operative position. It will be apparent from the drawing that there may be a plurality of such standard uniform operative positions of the seat 2 axially of the port 1 and said seat 2 may be moved to any such desired operative position axially of the port 1 according as may be necessitated by the particular type of tubing collar desired. To remove the seat 2, the same press may be employed and may exert its pressure radially inward so as to move the seat radially inward axially of the port 1 until it has been forced beyond the radially inner end of said port 1, when a new seat 2 may be inserted by the same press, or the seat may be inserted by introduction into the interior of the body D and forcing it radially outward to its proper operative position as shown in Figs. 1 and 2.

Preferably the inner face of the port 1 will be smooth, and as nearly uniformly circular as it is practical to attain by ordinary boring, grinding, reaming or polishing operations on a large scale quantity production and, subject to the same qualifications, the external peripheral face of the seat 2 will be as nearly truly circular as is to be had and will be as smooth as it can be made by usual grinding operations. Of course the cooperating parts of the present invention are to be considered in the light of their units and the conditions normally governing their production and assemblage and they are not to be regarded as scientific instruments of exactitute of precision and any slight variations from the truly circular such as are bound to occur under the above referred to conditions of quantity production will be taken care of by the inevitable slight deformation of the seat 2 incident to itsbeing forced into position under great pressure.

With a collar D of malleable cast iron formed with a port 1 having'an internal diameter of oneinch, and a valve seat 2 of Monel metal having an external diameter of one and two one-thousandths (1 2/1000) inches, at pressure of 2,000 pounds to the square inch is necessary to force or press the seat into proper position in the port 1, that is to say, to move the seat 2 in an endwise direction in the interior of the port 1. This pressure of 2,000 pounds per square inch is greatly in excess of any flowing pressures obtaining or applying to any oil wells known at the present time and is believed to be suflicient to be in excess of any pressure that would be encountered in any well that was under control, and hence to be sufficient to meet all conditions that may be encountered in any well under operative conditions.

In Figs. 1, 2 and 5 of the drawing, the port 1 is drawn to a diameter on a scale one-half of actual or full size and the same applies to the the same care as to maintaining definite relation between the proportions outwardly appearing in the drawing and proportions of the actual physical elements has not'been exercised as to them.

The valve seat 2 will be preferably formed of a double conical face construction, wherein the conical faces are formed in the respective end faces of the seat and converged radially inward- 1y toward each other at the same angle to the vertical, or preferably at the same angle to the vertical, or to a line extending at right angles to the axis of the seat and the profile of each said face will preferably be of the same length as the axial length of the outer peripheral cylindrical face of the seat, or in other words, the valve seat 2 will preferably be of equilateral triangle form in cross section with the base of thetrlangle constituting the radially outer face of the said seat 2. thus described my invention, what I claim new and desire to secure by Letters Patent is: v

l. A body termed with a port and with in mal in ccuinca'tion with port eat-ending from face to race through the wall of said body and being formed with a cylindrical portion and at all points throughout its length having. its least cross sectional dimension at least equal to the internal diameter of said cylindrical portion, in' combination with a valve seat forced into any desired position axially of said port and held inany such desired position to which it is forced solely by its frictional contact with the opposed wall of said cylindrical portion as held in compressed condition thereby, said valve seat having a peripherai face of greater diameter than the internal diameter of the cylindrical portion of said 'port prior to being forced therein.

2. A metallic body formed with. a port and with an internal passage in communication with said port, said port extending from face to face through the wall of said body and being formed with a cylindrical portion and at all points throughout its length having its least cross sectional dimension at least equal to the internal diameter of said cylindrical portion, in combination with a solid unbroken ring form, resilient metal valve seat forced into any desired position axially of said port and held in any such desired position to which it is forced solely by its frictional contact with the opposed wall oi said cylindrical portion as held in compressed condition thereby, said valve seat ha a peripheral race or greater diameter the internal diameter of the cylindrical portion of said port prior to being forced therein.

- a E RKGE,

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