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Publication numberUS3130789 A
Publication typeGrant
Publication dateApr 28, 1964
Filing dateAug 30, 1961
Priority dateAug 30, 1961
Publication numberUS 3130789 A, US 3130789A, US-A-3130789, US3130789 A, US3130789A
InventorsAlexander Thomas E, Nelson Wayne F
Original AssigneeKoehring Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Automatic fill-up and cementing devices for well pipes
US 3130789 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

April 28, 1964 T. E. ALEXANDER ETAL 3,

AUTOMATIC FILL-UP AND CEMENTING DEVICES FOR mam. PIPES HTTORNEVJ April 28, 1964 r. E. ALEXANDER ETAL ,7

AUTOMATIC FILL-UP AND CEMENTING DEVICES FOR WELL PIPES Filed Aug. 30, 1961 2 Sheets-Sheet 2 Tho/27am" f. A/exan a e/ Way/76% A/e/Jon INVENTORS ATTO/P/VEVJ United States Patent 3,130,789 AUTOMATIC FILL-UP AND CEMENTING DEVICES FOR WELL PIPES Thomas E. Alexander, Houston, and Wayne F. Nelson,

Waxahachie, Tex., assignors to Koehring Company,

Waxahachie, Tern, a corporation Filed Aug. 30, 1961, Ser. No. 134,932 Claims. (Cl. 166224) This invention relates to new and useful improvements in automatic fill-up and cementing devices for well pipes.

In well completion operations, it has been the practice to fill a well pipe, which is to be ultimately cemented in final position, as .such pipe is being lowered and various types of automatic fill-up and cementing devices have been in general use. Recently, the so-called tubingless completions, which eliminate the use of a well casing by utilizing the well tubing as the casing, are coming into more widespread use and because the well tubing is of considerably less diameter than the well casing heretofore employed, certain new problems are presented in connection with automatic fill-up and subsequent cementing of the smaller size well pipe.

For example, in tubingless completions, it is desirable to pump the cement downwardly at the highest possible rate so as to displace the mud in the annulus and the cement outlet should be completely unrestricted; also, after cementing is completed, it is essential that there be an immediate and positive closing of the back check or pressure valve to assure that there be no back leakage of cement because even a slight leakage will fill a considerable length of the smaller diameter pipe. Additionally, automatic fill-up of the pipe is desirable but at the same time, efiective protection against possible blow-out of the Well during lowering of the pipe should be provided.

Conventional fill-up and cementing devices designed primarily for use with the larger diameter well casing have been found inadequate for use in the tubingless completion field.

It is, therefore, one object of this invention to provide an improved fill-up and cementing device which is primarily adapted for use in running and cementing small diameter pipe, such as well tubing, within a well bore but which may, if desired, be employed with well casing or larger diameter pipe.

An important object is to provide a device, of the character described, having means for allowing a controlled or regulated fill of the pipe during lowering and which incorporates a full opening cementing valve, whereby maximum rate of cement pumping may occur; said valve being constructed to immediately and positively seal as a backpressure valve when the cementing operation is complete to prevent any reverse leakage of the cement into the well pipe.

Another object is to provide a device, of the character described, wherein a predetermined size orifice perrnits automatic controlled fill of the pipe during lowering and also wherein a normally open back check valve is associated with the orifice in such manner that any predetermined excessive entry of fluid through the orifice, such as might ultimately result in a blow-out, will atiect the back check valve and automatically move said valve to closed position to thereby provide protection against blow-out.

LA further object is to provide a fill-up and cementing device, of the character described, wherein the back check valve which functions to provide blow-out protection during lowering of the well pipe also acts as a cementing valve during a subsequent cementing operation; said valve being of an improved construction to assure a positive and leak-proof seal when in its seated position to prevent back flow of cement or other fluids into the well pipe.

3,130,789 Patented Apr. 28, 1964 A particular object is to provide a fill-up device having a valve element mounted therein, which element has its opposite sides exposed to the same annulus pressure and which is normally held in position permitting flow into the well pipe by a releasable means; a predetermined change in the differential pressures acting on opposite sides of the valve element, which change is caused by a predetermined increase in velocity of flow of fluid entering the pipe, resulting in release of said releasable means to automatically move the valve to a position closing said pipe to thereby protect the well against blow-out.

A still further object is to provide a device, of the character described, wherein a predetermined size orifice controls the filling of the well pipe and wherein a holding means requiring a predetermined force for release maintains the pipe closure valve in open position; the size of the orifice being so related to the force required to release the valve holding means that under normal flow of fluid into the pipe for filling purposes, the valve remains open but under excessive flow conditions the holding means is automatically released to move the valve to a position shutting off further entry of fluid into said pipe.

The construction designed to carry out the invention will be hereinafter described, together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

FIGURE 1 is a transverse vertical sectional view of a fill-up and cementing device, constructed in accordance with the invention and showing the parts thereof in the position during lowering of the pipe and normal controlled filling of said pipe;

FIGURE 2 is a similar view, illustrating the valve element of the device in its lowered position which it assumes during the cementing operation;

FIGURE 3 is a similar view, illustrating the valve element of the device in its upper position closing the lower end of the pipe against back-flow of fluid into the pipe;

FIGURE 4 is a horizontal cross-sectional view taken on the line 4-4 of FIGURE 1;

FIGURE 5 is a horizontal cross-sectional view taken on the line 55 of FIGURE 2;

FIGURE 6 is a schematic or diagrammatic view of a well bore showing the well pipe having the improved device at its lower end being lowered into the well bore during which time a controlled filling of the well pipe with liquid from the annulus is accomplished;

'FIGURE 7 is a view similar to FIGURE 6 illustrating the position of the parts during the introduction of cement into the well bore; and

FIGURE 8 is a similar view showing the valve element of the device in its back-check position preventing a reverse flow of fluid into the lower end of the pipe.

In the drawings, the numeral 10 designates a cylindrical tubular body having a bore 11 extending entirely therethrough. The lower end of the bore of the body is closed by a plug 12 which is preferably threaded into said lower end. An annular inclined valve seat 13 is provided in the upper portion of the body and above the valve seat a threaded box 14 is formed whereby the well pipe or tubing T may be connected therewith in the usual manner. Spaced below the annular valve seat 13 is a filling port 15 which is constructed of a predetermined size and which will permit an inflow of fluid from the area outside of the body into the bore and then upwardly into the well pipe or tubing T, as will be hereinafter explained. Spaced downwardly from the filling port or orifice 15 are a plurality of cementing ports 16, and as is clearly shown in FIGURE 2, a number of these ports are provided. With small pipe the combined cross-sectional area of the cementing ports should be at least as great as the cross-sectional area of the bore 31 of the well pipe or tubing string T, whereby when cement is pumped downwardly through said well pipe, the cementing ports do not form a restriction to the flow of cement outwardly into the area around the body 10. With large pipe a port area less than the crosssectional area of the pipe may be adequate as cement will be introduced to the pipe from smaller surface piping. In any case the port area should not be such as to cause a restriction. Nearer the lower portion of the body are a plurality of fluid equalizing openings 17 so that pressures inside and outside of the body may equalize in the lower portion thereof above the plug element 12.

A valve element generally indicated at A is slideable within the bore 11 of the body and, as will be explained, is adapted to coact with the cementing ports 16 and also with the filling orifice or port 15. The valve element includes a main valve body 18 having a closed upper end which is preferably substantially fiat throughout its major area. The outer peripheral edge portion of said upper surface is inclined or beveled at 19 to form a valve sealing surface which under certain conditions is engageable with the internal valve seat 13 within the upper end of the body. Immediately below the sealing surface 19, the valve body has a pair of O-rings 20 mounted within suitable annular recesses 21 and said O-rings seal between the external surface of the valve body 18 and the bore 11 of the body. The lower end of the valve body is reduced to provide a depending annular skirt 22 and at the intersection of said skirt with the main body an external annular shoulder 23 is formed. A coiled spring 24 is preferably confined within the lower portion of the body with its upper end in engagement with the annular shoulder 23 and its lower end engaged with the closure plug 12. The spring exerts its force to constantly urge the valve element A upwardly within the body. It might be noted that although it is preferable to employ the spring 24, it has been found that such spring could be omitted.

The valve element A is normally retained within the body in the position shown in FIGURE 1 by a frangible shear pin 25, said pin extending through the wall of the body and into a recess 26 in the exterior surface of the valve element. As will be explained in detail, the strength of the shear pin 25 is related to the size of the fill port and when the shear pin is connected with the valve element A (FIGURE 1), said valve element overlies the cementing ports 16 to close the same. The O-rings on the valve element seal with the wall of the body bore 11 and prevent any How of fluid from the area above the valve element outwardly through the ports 16. The length of the valve element is such that when in the position of FIGURE 1, its upper end is below the fill port 15 while its lower end is above the equalizing ports 17; obviously, the upper end of the valve element is spaced downwardly from the internal valve seat 13 which is provided in the upper portion of the valve body. With such arrangement, the cementing ports 16 are closed and fluid from the area outside of the body may flow through the filling port 15 into the well pipe or tubing string T. This same pressure may enter the ports 17 and is present in the area below the valve element so that, in effect, under static conditions, pressures above and below the valve element are equalized. The coiled spring is tending to urge the valve element upwardly but the shear pin which connects the valve element in the position of FIGURE 1 prevents such upward motion.

The pin 25 may be sheared under one of two conditions which may occur. If a sufiicient pressure is applied to the upper end of the valve element A, as for example by pumping cement downwardly through the well pipe or string T, the pin 25 will be sheared which will move the valve element A downwardly to the position shown in FIG. 2 to uncover the cementing ports. Under such condition. cement may be pumped outwardly through the ports 16 into the area outside of the body 10 and it is noted that at this time the valve sealing surface 19 as well as the O-rings 20 are below the cementing ports and neither the sealing surface or the O-rings will be affected by the abrasive action of the cement fluid. Upon completion of a cementing operation, the coil spring 24 will move the valve to the position shown in FIGURE 3 and in such position the beveled sealing surface 19 of the valve element 8 engages the internal seat 13 to effectively close any upward flow into the well pipe. The O-rings will assist in effecting a positive back-check seal.

The second condition under which the pin 25 may be sheared to permit a movement of the valve element A is upon a predetermined pressure diflerential occurring across the valve element. As has been noted, when the pipe is being lowered with the valve element A connected by the shear pin 25 and maintained in the position of FIGURE 1, fluid from outside the body may enter the orifice 15 and enter the well pipe. The same pressure may also enter the equalizing ports 17 so that under normal filling conditions the pressures across the valve element are not great enough to shear the pin. There will of course be a slightly lesser pressure in the area immediately above the valve element than the static pressure which is acting on the lower end of the element, this being caused by the fact that there is an upward flow into the well pipe. The strength of the shear pin is so related to the size of the port 15 that under normal filling conditions the parts will remain in the position of FIGURE 1. However, if there is a tendency for the well to blow-out, the velocity of flow through the control orifice 15 will be increased and the upward velocity into the well pipe will increase accordingly to thereby result in a reduction in pressure above the valve element. By relating the size of the port 15 to the shear pin 25, it is possible to cause a shearing of the pin by the static pressure acting underneath the valve element when a predeter mined pressure drop occurs above the element. When such predetermined pressure drop occurs, the pin 25 is sheared and the valve element A is moved to the position of FIGURE 3; in such position, its sealing surface 19 engages the internal valve seat 13 and the O-rings 20 seal with the wall of the bore 11 of the body above the filling port or orifice 15 and an effective back-check or back-flow valve is thus provided.

Specific examples of the operative relation between the size of the port 15 and the strength of the shear pin are now set forth. For instance, assuming that a 4"-20 shear screw retaining a valve element having an effective pressure diameter of 3%" is to be sheared when 10 pound mud is flowing through the orifice at the rate of gallons per minute, then the orifice should be approximately 0.624" in diameter. Under similar circumstances but using a "-18 shear screw, the diameter of the orifice should be approximately 0.551".

In the operation of the improved fill-up and cementing device, reference is made to FIGURES 6 through 8 in which the device is connected to the lower end of a tubing string T which is adapted to be lowered within a well bore W. A short section of surface casing 26 is set within the well bore W and has the usual tubing head 27, which is shown schematically mounted at its upper end. The head has a fluid outlet 28 controlled by a suitable valve 29 and also includes a conventional packing or seal 30 which seals off the annulus between the well bore W and the tubing T.

The shear pin 25 is positioned to connect the body 10 with the valve element A and to dispose said valve element in the position shown in FIGURE 1 and as the tubing string T is lowered the fluid, which is generally drilling mud from the annulus, flows through the fill-up port or orifice 15 and provides for an automatic controlled filling of the tubing string during the lowering operation. By relating the size of the orifice or port 15 to the strength of the shear pin 25, a controlled or predetermined amount of fluid may flow into the tubing and the pressure differential created across the valve element A will be insufiicient to shear said pin 25. Thus, during lowering of the tubing string and with conditions normal, a predetermined amount of fluid is introduced into the tubing to fill said tubing automatically.

In the event that the fluid within the annulus begins to enter the port or orifice at a rate which might cause a blow-out of the well, the velocity of flow of liquid upwardly in the tubing is increased and this increased velocity results in a reduction in the pressure which is acting against the upper end of the valve element A. The lower end of the valve element, as has been explained, is constantly exposed to the static fluid head and when the reduction in pressure above the valve element A is sufficient, the pressure acting below the valve element will shear the pin 25 and move the valve element A to the position shown in FIGURES 3 and 8. In such position, a back flow of any fluids into the tubing string T is effectively prevented because the sealing surface 19 of the valve element is in engagement with the internal valve seat 13 within the upper portion of the body. Also, the O-ring seals are engaged with the bore 11 of the body in the area between the internal seat 13 and the orifice or port 15 and thus such port is effectively closed. The pressure below the valve element maintains it in its back-check sealing position and thus positive protection against blow-out is provided.

In the event that the tubing string T is lowered to final position within the well bore W without there having been any occurrence which might tend to cause a blowout, then the cement is pumped downwardly through the tubing string T in the usual manner. This is illustrated in FIGURE 7 and the pressure of such cement is applied against the upper end of the valve element A to shear the pin and move the valve element downwardly to the positions shown in FIGURES 2 and 7. In such positions the large cementing ports 16 are uncovered and the cement may be rapidly introduced into the annulus to displace the mud or fluid within the annulus upwardly; of course, at this time, the valve 29 in the line 28 at the upper end of the annulus is opened to permit displacement of said mud. Upon completion of the cementing operation, the reduction of pressure in the tubing string permits the valve element A to be immediately moved into its seated, back-check position as shown by FIG- URES 3 and 8. The upward movement of the valve to back-check position is eflected primarily by the pressure acting below the valve element and where the coil spring 24 is employed, such spring adds its force to the pressure to assure seating of the valve. It is noted that during the cementing operation the upper surface of the valve element A is below the cementing ports 16 so that the annular surface 19 and the O-rings 20 are not exposed to the abrasive action of the cement. This means that the surface 19 and the O-rings 20 will etiectively and immediately move into sealing position when the valve element is moved upwardly.

From the foregoing it will be seen that a simple and effective fill-up and cementing device is provided. By controlling the size of the inlet orifice or port 15, a predetermined volume of fluid from the annulus will flow into the tubing string during the lowering operation. Under normal conditions, the valve element A is maintained in the position of FIGURE 1 closing the cementing ports and the shear pin 25 remains intact. In the event of any excessive increase in velocity of the fluid flowing upwardly in the tubing, a pressure reduction occurs above the valve element and when such reduction is to a predetermined point in accordance with the strength of the shear pin 25, the pin is sheared and the valve is moved upwardly to provide blow-out protection. It, on the other hand, the tubing is lowered into final position without any tendency for blow-out, the valve element has remained in the position of FIGURE 1 with the shear pin 25 connecting the same to the body. Upon the application of pressure through the cement column which is to be pumped into the well, the pin 25 is sheared to move the valve element A downwardly and uncover the large cementing ports which permits a rapid pumping of cement into the annulus. Upon completion of cementing, the valve is immediately moved to its back-check or closing position, as shown in FIGURE 3, to prevent any back leakage of cement into said tubing string. Although it has been found that a shear pin or other frangible means is a simple way of latching or holding the valve element in position, other types of latches could be employed. Any latch or holding means which maintains the valve element A in its position as shown in FIGURE 1 would, of course, be related to the size of the fill port or orifice 15 so that the force required to release the valve element for upward movement under predetermined pressure difierential conditions may be controlled. The proper relationship between the port 15 and the force required to release the valve element for movement upwardly may be predetermined and will, of course, be varied in accordance with the particular conditions of the well in which the device is to be used.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction, may be made within the scope of the appended claims without departing from the spirit of the invention.

What we claim is:

1. A fill-up device including, a tubular body having means for connecting said body in a well pipe string, said body having an orifice establishing communication between the exterior and interior thereof whereby fluid from the annulus surrounding the body and pipe string may flow through the orifice and into the string, a piston valve element mounted for movement within the body and movable to a position closing flow into the pipe string, said valve element being subjected to the pressure of the fluid flowing through said orifice into the pipe string, said valve element having means coacting with said tubular body to prevent flow through said orifice when said valve element is moved to said position closing flow into the pipe string, releasable means for normally holding said valve element in a position allowing flow through the orifice and into the pipe string, said releasable holding means being released by the differential pressure caused by a predetermined increase in the velocity of fiow of fluid passing through said orifice to permit movement of the valve element, said diflerential pressure also moving the valve element to a position closing further flow into the pipe string.

2. A fill-up device including, a tubular body having means for connecting said body in a well pipe string, said body having an orifice establishing communication between the exterior and interior thereof whereby fluid from the annulus surrounding the body and pipe string may flow through the orifice and into the string, a piston valve element slideably mounted within the bore of the tubular body and movable to an upper position closing flow into the pipe string, said valve element having means coacting with said tubular body to prevent flow through said orifice when said valve element is moved to said position closing flow into the pipe string, a releasable means for normally holding said valve element in a lowered position allowing flow through the orifice and into the pipe string, said last-named means being releasable upon the application of a predetermined force against the valve element, the upper surface of said valve element being exposed to the pressure of the fluid flowing through the orifice and entering the string, means for exposing the lower surface of said element to the static pressure of the fluid in the annulus exteriorly of the body, a predetermined increase in the velocity of the fluid flowing through said orifice and into the pipe string resulting in a reduction in the pressure acting against the upper surface of the element,

whereby the pressure differential across the element creates the required force to release the releasable holding means and to thereafter move the valve element to an upper position closing further flow into the pipe string.

3. A fill-up device as set forth in claim 2, wherein the releasable valve element holding means is a shear pin.

4. A fill-up device as set forth in claim 2, together with a spring means within the body below the valve element and exerting its force to constantly urge the valve element toward an upper position within the body.

5. A fill-up and cementing device including, a tubular body having bottom closure means and having means for connecting said body in a well pipe string, said body having an orifice located nearer its upper end and establishing communication between the annulus outside the body and string and the interior of the body and string, said body having cementing ports below said orifice and having equalizing openings spaced below said cementing ports and disposed nearer the lower end of the body, a piston valve element slideably mounted within the body and movable to an upper position closing flow through the orifice and into the pipe string and also movable to a lower position to uncover the cementing ports, said valve element having means coacting with said tubular body to prevent flow through said orifice when said valve element is moved to said position closing flow into the pipe string, releasable means for normally retaining the valve element in a position intermediate the orifice and the equalizing openings in which position the cementing ports are covered and closed, said releasable means being releasable by a predetermined force applied to the valve element, the upper surface of said valve element being exposed to the pressure of the fluid flowing through the orifice and into the pipe when the valve element is releasably retained in its intermediate position and the lower surface being exposed to the static pressure of the fluid in the annulus exteriorly of the body, whereby the valve element is subjected to the pressure-differential forces on opposite sides thereof, said releasable retaining means being released either by the existence of a predetermined pressure-differential across said valve element which is created by a predetermined increase in velocity of flow through the orifice and into the pipe string in which event the valve element is moved upwardly to close flow into the string or which is created by an increase in pressure applied against the upper end of the valve element through the pipe string in which event the valve element is moved downwardly to uncover the cementing ports.

6. A fill-up and cementing device as set forth in claim 5, wherein a spring means is mounted within the body below the valve element and exerts its force to constantly urge the valve element toward its upper position.

7. A fill-up and cementing device as set forth in claim 5, wherein the releasable retaining means is a frangible shear pin having a strength related to the size of the orifice, whereby a predetermined increase in velocity of flow through the orifice effects a predetermined increase in pressure-differential on opposite sides of the valve element which will fracture said shear pin.

8. A fill-up and cementing device as set forth in claim 5, wherein the releasable retaining means is a frangible shear pin having a strength related to the size of the orifice, whereby a predetermined increase in velocity of flow through the orifice effects a predetermined increase in Cit pressure-differential on opposite sides of the valve element which will fracture said shear pin, and a spring means mounted in the body below the valve element and exerting its force in a direction to constantly urge the valve element upwardly.

9. A fill-up and cementing device as set forth in claim 5, together with an internal annular valve seat formed within the body spaced above the orifice, said valve element being generally cylindrical and having an annular valve sealing surface engageable with said valve seat when in its upper position, and sealing rings mounted on the upper portion of the valve element below the valve sealing surface and engageable with the bore of the body to seal therewith.

10. A fill-up device including,

a tubular body having bottom closure means and having means for connecting said body in a well pipe string,

said body having an orifice establishing communication between the exterior and interior thereof whereby fluid from the annulus surrounding the body and pipe string may flow through the orifice and into the string,

an internal annular valve seat formed within the body spaced above the orifice,

a piston valve element slidably mounted within the bore of the tubular body and movable to an upper position closing flow in the pipe string,

said valve element being generally cylindrical and having an annular sealing surface engageable with said valve seat when in its upper position,

sealing rings mounted on the upper portion of the valve element below the valve sealing surface and engageable with the bore of the body to seal therewith, said valve element having means coacting with said tubular body to prevent flow through said orifice when said valve element is moved to said position closing flow into the pipe string,

releasable means for normally holding said valve element in a lowered position allowing flow through the orifice and into the pipe string,

said last-named means being releasable upon the application of a predetermined force against the valve element,

the upper surface of said valve element being exposed to the pressure of the fiuid flowing through the orifice and entering the string,

a predetermined increase in the velocity of the fluid flowing through said orifice and into the pipe string resulting in a reduction in the pressure acting against the upper surface of said valve element, whereby the pressure differential across said valve element creates the required force to release the releasable holding means and to thereafter move the element to an upper position closing further flow into the pipe string.

References Cited in the file of this patent UNITED STATES PATENTS 2,033,563 Wells Mar. 10, 1936 2,698,054 Brown et al. Dec. 28, 1954 2,846,015 Pittman Aug. 5, 1958 2,847,074 Maly et a1 Aug. 12, 1958 2,874,785 Muse Feb. 24, 1959

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4125289 *Dec 23, 1977Nov 14, 1978Kennecott Copper CorporationMethod for in situ minefields
US4311197 *Jan 15, 1980Jan 19, 1982Halliburton ServicesAnnulus pressure operated closure valve with improved reverse circulation valve
US4445571 *Aug 20, 1981May 1, 1984Halliburton CompanyCirculation valve
US4487221 *Nov 16, 1981Dec 11, 1984Klaas ZwartDevice for temporarily sealing a pipe
US5355959 *Sep 22, 1992Oct 18, 1994Halliburton CompanyDifferential pressure operated circulating and deflation valve
US5445224 *Sep 1, 1994Aug 29, 1995Comeaux; Luther R.Hydrostatic control valve
Classifications
U.S. Classification166/317, 166/325
International ClassificationE21B21/00, E21B34/06, E21B21/10, E21B34/00
Cooperative ClassificationE21B34/063, E21B21/10
European ClassificationE21B34/06B, E21B21/10