US2631673A - Apparatus for and method of discharging liquid - Google Patents

Description

g 1 6 3 y i AAA March 17, 1953 M. H. HALDERSON ET AL 2,631,673

APPARATUS FOR AND METHOD OF DISCHARGING LIQUID Filed July 15, 1948 2 SHEETS-SHEET l ,"m/aw AM INVENTORS W.L.MORR|S M.H. HALDERSON A T TORNE Y March 1953 M. H. HALDERSON ET AL 2,631,673

APPARATUS FOR AND METHOD OF DISCHARGING LIQUID Filed July 15, 1948 2 SHEETS-SHEET 2 A T TORNEYS Patented Mar. 17, 1953 APPARATUS FOR AND METHOD OF DISCHARGING LIQUID Maxwell H. Halderson and William L. Morris,

Bartlesville, kla., assignors to Phillips Petroleum Company, a corporation of Delaware Application July 15, 1948, Serial No. 38,886

This invention relates to a method of and apparatus for discharging liquid, such as acid, into a drill hole. In another aspect, it relates to a tool which is adapted to be lowered into a drill hole to discharge vortices of liquid against the wall surface thereof.

Previous methods of acidizing drill holes have ordinarily contemplated the use of a jet of acid which is directed against the side walls of the drill hole. Where a jet is used, considerable mixing occurs between the acid and the fluid in the bore hole and it is necessary that the pipe or nozzle from which the jet flows be steadily advanced into the opening produced by the acid in the side of the drill hole. This requires expensive and complicated equipment including a tube extending into the well for operating the jet.

We have discovered that difliculties inherent in the use of jets can be overcome by the use of vortices in the acidizing of drill holes. The vortices used in this invention are annular or doughnut shaped masses of fluid which move along their axes with a whirling motion along their cross sections, in a similar manner to the propagation of a common smoke ring through the atmosphere. In order to produce vortices, it is necessary that the elastic properties of the vortices and the medium through which they travel be of the same order of magnitude. For example, smoke rings occur in the air while liquid vortices occur in a liquid. The vortices with which we are concerned occur only in annular configurations and cannot take any other form without disintegrating. Further, they travel in a straight line and retain their shape until striking a barrier, or the like, where they break up and thereby discharge the stored energy represented by the whirling movement along their cross sections in an intense scouring action against the barrier. Until the barrier is struck, the vortices maintain substantially all the energy with which they are released and the fluid constituting each vortex does not mix with the fluid through which the vortex is traveling until it is broken up by meeting a barrier or other obstruction. Thus, a smoke ring maintains its shape and does not mix with air while an ink vortex traveling through water does not mix therewith. Accordingly, when acidizing wells, a considerable saving in the amount of acid required for a given formation may be made, since the acid vortices are not diluted by mixture with the well liquids before engaging the formation or wall of the bore hole. These properties of vortices make them particularly desirable for use in acidizing wells in the manner 2 set forth in the following specification and defined by the claims.

The present invention contemplates a tool of simple construction which is adapted to be lowered into a drill hole by a wire line, without the use of tubing, this tool including an acid reservoir from which liquid is forcibly directed through a small orifice against the sides of the drill hole. Preferably, the orifice is circular, with the result that each forcible ejection of fluid produces an annular vortex which travels through the fluid or drilling mud in the well and engages the sides thereof.

The invention is particularly suitable for acid\ izing cavernous limestone formations. By the use of acid vortices, a hole is formed which may extend four or flve feet to a cavity, and no vertical solution will occur. As a result, subsequent entrance of salt water into the well from below the cavity is effectively prevented.

Although the present invention finds its main application in acidizing drill holes, we also con-\ template that liquid vortices may be used in i selective p f ter ora'idfiTo *w m ubing'dr a'itema 'f tively, we contemplate that the vorticesforme W merbausedtqsmunan.accn a ci iltenca serironrsulfidel.anchother.substanc Lcm.thesnrfacepiafcrmationcinlacslrillhole... c.

It will be noted that the use of vorticesin acidizing provides a number of important advantages not obtainable with the jets utilized in the prior art. Thus, jets of acid soon lose their original energy after release while the vortices do not. The fluid of a jet tends to mix with the surrounding fluid, thus resulting in dilution before the jet reaches the formation or walls, of the drill hole, While the vortices do not mix with the drill hole fluids until after they have expended their energy. The directional eifect obtained in the use of jets is lost as soon as the cavity in the formation becomes large, while vortices maintain their directional effect until their energy has dissipated by colliding with the side of the bore hole. The intense scouring action obtained from vortices cannot be obtained from a jet. The large volume of acid used with jets permits quantities of acid to act on the bottom of a well, but this will not occur with the small amount of acid used with vortices. Acid acting on the bottom of a well may eat into a water bearing formation and thus prove a detriment to the well. The action of the vortices is so far superior to that of the jet that only a comparatively small amount of acid is used in the present system. This small amount of acid may be readily stored within a reservoir in the vortex tool whereas, if jets were used, it would be necessary to run a string of tubing down the well to the formation being acidized.

It is an object of the invention to provide an improved method of and apparatus for producing liquid vortices in drill holes which may be utilized to acidize the well or clean formations from the walls of the drill hole.

It is a further object of the invention to provide a vortex-producing tool which is adapted to be lowered into a drill hole.

It is a still further object of the invention to provide apparatus which is simple in construction, reliable in operation, and which may be manufactured at a low cost.

Various other objects, advantages and features of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

Figure 1 is a vertical sectional view of the apparatus of this invention mounted in a bore hole;

Figure 2 is a vertical sectional view of the tool for producing liquid vortices;

Figures 3, 4 and are, respectively, sectional views taken along the lines 3-3, 4-4, and 5-5 of Figure 2, looking in the direction of the arrows; and

Figure 6 is a vertical sectional view of a vortex.

Referring now to the drawings in detail, and particularly to Figure 1, we have shown a drill hole H), the lower portion of which is filled with a fluid ll, such as water or a mixture of water and drilling mud. Our novel vortex generating tool I2 is suspended within the drill hole In by a cable I3 carried by a Windlass, not shown, which may be raised and lowered in the drill hole by any suitable power source. The tool I2 has a discharge orifice 20 formed therein and vortices of liquid material 2|, such as acid, are successively discharged through this orifice against the surface of the drill hole It], thereby forming an enlarged hole in the formation. One of the vortices 2| is shown by Figure 6, from which it will be noted that the vortex consists of an annular body of liquid which is propagated through the liquid II in the bore hole along its axes 2|a, the direction of propagation being as indicated by the arrow. Further, the annular mass of liquid has a whirling motion along its cross section as indicated by the two sets of arrows positioned above and below the axis of the vortex. When a number of these vortices successively engage the walls of the drill hole, as

by Figure 1, an intense scouring ag tig r results due to the release of the stored energy represented by the whirling movements of the vortices. In addition, the vortices are highly selective in their action and do not tend to mix with the fluid medium surrounding the tool The detailed construction of the tool I2 is shown by Figures 2 to 5, inclusive, and this tool includes a generally cylindrical casing 22 having a liquid reservoir 23 formed at the top thereof which is provided with an inlet 24 and which communicates through a line 25 with a piston or pressure chamber 26. A pressure equalizing line 21 connects the upper end of the reservoir with the pressure chamber 26 and permits equalization of the pressure in these chambers, thereby insuring a free flow of fiuid by gravity from the reservoir into the piston chamber.

The discharge orifice 20, as clearly shown by Figures 2 and 4, is of circular cross section and connects the lower or outlet portion of the chamber 26 with the exterior of the tool.

A piston 30 is mounted for reciprocatory movement in the chamber 26 and it is connected to a piston rod 3| which extends through suitable sealingmeans 32 at the top of the chamber. The rod 3| is encircled by a heavy compression spring 33 which forcibly urges thepiston toward the bottom or outlet portion of the chamber. This piston is also provided with one way valves 35 which permit liquid to pass from the upper portion of the chamber to the lower portion when the piston rises but which prevent such flow of liquid as the piston descends in the chamber. The piston is moved upwardly to store energy in spring 33 by mechanism which includes a'bifurcated operated lever 36 which is pivoted at the top portion of rod 3| and which is biased to a predetermined upright or vertical position by springs 31. Each arm of the lever 36 has a transversely bent end portion 39 which may be engaged by a hooked catch 40 protruding from a wheel 4|, and both of the wheels are driven by a motor 42 through a shaft 43. Power may be supplied to the motor 42 by suitable leads, not shown, extending through the casing 22 and carried by the cable [3, as those skilled in the art will understand. Alternatively, a battery, not shown, may be mounted within the casing 22 and connected to the motor by suitable conductors. A spring 45 urges each catch 40 in a radial direction to the position shown by Figures 2 and 3 and each catch has a stud 46 projecting therefrom which rides in a slot 41 formed in the associated wheel 4|. Assuming that the motor rotates each wheel 4| in a counterclockwise direction, Figure 3, it will be apparent that the catches 46 engage the respective protruding portions 39 of lever 36 and thereby move this lever together with the piston 30 in an upward direction with the result that spring 33 is compressed and a considerable amount of energy is stored therein.

When the wheels 4| reach a predetermined angular position, each stud 46 engages a stop 48 with the result that each of the catches 40 is moved radially inward of its wheel 4| and is thereby disengaged from the operating lever 36. Thereupon, spring 33 forces the piston 3|] downwardly in an abrupt manner and the lever 36 returns to the upright position to which it is biased by springs 31 until it is again engaged by the catches 46.

Assuming that a supply of liquid, such as acid, is contained within reservoir 23, it will be apparent that, during the downward stroke of the piston, a quantity of liquid is abruptly discharged through orifice 20 from the lower portion of chamber 26, this abrupt discharge resulting from the sudden release of the energy stored in spring 33. The piston then remains at the bottom of the chamber until the next engagement of catches 46 with operating lever 36 and, during this period, liquid flows into the upper portion of the chamber through line 25 from the reservoir 23. When the lever is again engaged by catches 46, the piston is raised, thereby opening one way valves 35 and permitting liquid to flow from the upper portion of the chamber 26 into the lower portion thereof. This upward movement of the piston also stores energy in spring 33 which is abruptly released when the operating lever 36 is disengaged from catches 40 by the next engagement of studs 46 with the respective stops 48.

Accordingly, the'piston 30 and associated apparatus functions as a spring loaded pump in which the spring 33 produces an abrupt power or discharge stroke while the motor 42 operating through wheels 4|, catches 40 and lever 3| effects the return stroke of the piston which stores energy in spring 33 for the next succeeding power stroke.

In accordance with the invention, we also provide an outlet valve or gate 50 for opening and closing the orifice 20. The valve 50 is actuated by a rod and it is biased toward its closed position by a spring 52, one end of which engages the casing at 53 and the other end of which engages a collar 54 formed on the rod 5|. The upper end of rod 5| is bent over, as indi-- cated at 55, and this bent portion extends through a slot 56 in the outer wall of the casing. An operating lever 58 is pivoted to the bent rod 55 and this lever is biased to a predetermined vertical or upright position by springs 59. The lever 58, in turn, has a bent end portion' 60 which is engaged by a catch 6| carried by an extended portion 62 of one of the Wheels 4|. The construction of catch BI is precisely similar to that of the catches 40 and, accordingly, as the wheel rotates, the catch 61 engages the lever portion 60 and raises it together with the rod 5| and valve 50, until a stud on catch 6| engages a stop 64 when the wheel has rotated a predetermined angular distance. Thereupon, the lever 58 is released bycatch BI and valve 50 is immediately closed by spring 52, the valve remaining closed until catch 6| once again engages the bent end portion 60 of lever 58 during the succeeding revolution of wheel 62.

The catch 6| is displaced 180 degrees with respect to the catches 40 with the result that the piston 30 and valve 50 operate in timed relation, the valve being opened during the downward power stroke of the piston to permit an abrupt discharge of fluid through orifice 20 and the valve being closed during the upward return stroke of piston 30 to prevent the fluid in the bore hole from entering the chamber 26 during such return stroke. It will be evident that the positionof the catches 40, 6| may be varied as desired to change the length of stroke of the piston, and thereby vary the amount of liquid ejected at each stroke. The size of the piston chamber, 26 and orifice 20 may also be varied to accomplish the same effect. The pressure within the casing 22 may be equalized with that existingoutside the casing by any suitable device, such as the pressure-equalizing bellows shown at page '75 of the Oil and Gas Journal, March 15, 1947.

Where the orifice 20 is of circular cross section, the abrupt discharge of liquid or acid therethrough caused by each sudden release of spring 33 produces an annular vortex which is propagated through the liquid medium surrounding the tool I2. Positive operation of the piston 30 and valve 50 is insured by the spring loading thereof and the catch mechanisms '40, 6| insure maintenance of the proper timed relation between the opening and closing of valve 50, and the power and return strokes of piston 30 so that successive vortices having a large amount of stored energy are produced. Preferably and advantageously, the tool I2 is used as shown in Figure 1 for acidizing drill holes. The clinging and scouring action of the vortices against the sides of the drill hole is so pronounced, however, that the vortices may be used for producing perforations in the steel sides of a drill pipe. Alternatively, the reservoir may be filled with water and the vortices used to scrub filter cake, iron sulfide, or other substances from the side of the drill hole.

While the invention has been described in connection with a present, preferred embodiment thereof, it is to be understood that this description is illustrative only and is not intended to limit the invention, the scope of which is defined by the appended claims.

Having described our invention, we claim:

1. A tool for intermittently discharging liquid into a drill hole which comprises, in combination, a casing adapted to be lowered into a drill hole, a liquid reservoir in said casing, means defining a discharge orifice in said casing, a pres sure chamber formed in said casing, a piston mounted for recipro-catory movement in said chamber, said piston dividing said chamber into an inlet portion and an outlet portion communicating with said orifice, a one Way valve in said piston for permitting flow of liquid from said inlet portion to said outlet portion, a line for conveying liquid from said reservoir to said inlet portion, a spring biasing said piston toward the outlet portion of said chamber, and means for cyclically moving said piston toward the inlet portion to store energy in said spring and thereafter releasing said piston to effect abrupt discharge of liquid through said orifice by the action of said spring, an outlet valve for said orifice, and means for opening said valve during the discharge stroke of said piston and for closing said valve during the return stroke of said piston.

2. A tool for intermittently discharging liquid into a drill hole which comprises, in combination, a casing adapted to be lowered into a drill hole, a liquid reservoir in said casing, means defining a discharge orifice in said casing, a, pressure chamber formed in said casing communicating with said orifice and said reservoir, a piston mounted for reciprocatory movement in said chamber, a spring for effecting abrupt movement of said piston in one direction to provide a power stroke, and means for moving said piston in the opposite direction to compress said spring and provide a return stroke comprising a control lever pivotally mounted on said piston, means biasing said control lever to a predetermined angular position, a motor, a wheel driven thereby, a catch on said wheel which is 'engageable-with said lever to move the piston in said opposite direction, and means for releasing said catch when said wheel reaches a predetermined angular position to permit said spring to move the piston and provide a subsequent power stroke.

3. A tool for intermittently discharging liquid into a drill hole which comprises, in combination, a casing adapted to be lowered into a drill hole, a liquid reservoir in said casing, means defining a discharge orifice in said casing, a pressure chamber communicating with said orifice and said reservoir, a piston mounted for reciprocatory movement in said chamber, a spring for efiecting abrupt movement of said piston in one direction to provide a power stroke, means for moving said piston in the opposite direction to compress said spring and provide a return stroke, said last mentioned means comprising a control lever pivotally mounted on said piston,

means biasing said control lever to a predetermined angular position, a motor, a wheel driven thereby, a catch on said wheel which is en able with said lever to move the piston in said opposite direction, and means for releasing said catch when said wheel reaches a predetermined angular position to permit said spring to move the piston and provide a subsequent power stroke, a valve controlling said discharge orifice, a spring biasing said valve to closed position, a second control lever for operating said valve, a second wheel driven by said motor having a catch thereon for moving the second operating lever so as to open said valve, and means for releasing said second catch at the beginning of each return stroke of said piston, thereby to abruptly close said valve.

4. A tool for intermittently discharging liquid into a drill hole which comprises, in combination, a casing adapted to be lowered into a drill hole, a liquid reservoir in said casing, a discharge orifice in said casing, a spring loaded outlet valve for opening and closing said orifice, a pressure chamber communicating with said orifice, a line connecting said chamber and said reservoir, a spring loaded piston in said chamber for effecting an abrupt discharge of liquid through said orifice, and means for operating said piston and said valve in timed relation so that the valve is opened at the beginning of each power stroke of the piston and closed at the beginning of each return stroke of the piston.

5. A tool for intermittently discharging liquid into a drill hole which comprises, in combination, a casing adapted to be lowered into a drill hole, a liquid reservoir in said casing, a discharge orifice in said casing, a spring loaded outlet valve for opening and closing said orifice, a pressure chamber communicating with said orifice, a line connecting said chamber and said reservoir, a spring loaded piston in said chamber for effecting an abrupt discharge of liquid through said orifice, and means for operating said piston and saidvalve in timed relation comprising a motor driven catch mechanism for alternately moving said piston and said valve so as to compress the respective springs associated therewith, and means for alternately releasing said piston and said valve to effect an abrupt discharge of liquid through said orifice while the valve is open and to effect an abrupt-closure of said valve at the beginning of the return stroke of said piston.

6. A tool for intermittently discharging liquid into a drill hole which comprises, in combination, a casing adapted to be lowered into a drill hole, a liquid reservoir in said casing, means defining a discharge orifice in said casin an outlet valve for opening and closing said orifice, means biasing said valve toward closed position, an operating lever for said valve, a motor, a wheel driven thereby, a catch on said wheel for moving said operating lever to open said valve, means for releasing said catch upon movement of said lever to a predetermined position whereby said valve is abruptly closed by said biasing means, a piston mounted in said casing in a chamber having an inlet portion on one side of said piston and an outlet portion on the other side of said piston communicating with said discharge orifice, a spring biasing said piston in a direction to discharge fluid from said outlet portion through said orifice, a line for feeding liquid from said reservoir to said inlet portion of the piston chamber, a bleeder line for connecting and thereby equalizing the pressures in the upper part of said reservoir and said inlet portion of the piston chamber, a one way valve in said piston permitting flow of liquid from said inlet portion to said outlet portion, a lever for moving said piston, means for operating said piston lever to move said piston and thereby compress said spring, said movement of the piston permitting liquid to flow through said one way valve into the discharge portion of said chamber, said operatin means including a second wheel driven by said motor, a catch on said second Wheel for engaging said piston lever, and means for releasin said catch upon movement of said piston lever to a predetermined position, whereby said spring abruptly moves said piston to cause forcible ejection of fluid through said orifice, said catches being so positioned upon their respective wheels that the piston is moved to eject fluid While the outlet valve is in open position and said outlet valve is closed during the return stroke of said piston.

7. In the art of acidizing liquid-containing drill holes, the steps which comprise directing a circular orifice toward the walls of the drill hole, and intermittently applying high pressure to a body of acid to force same through aid orifice at high velocity, whereby a plurality of vortices are formed which move through said liquid to the Walls of the drill hole.

8. In the art of treating liquid-containing drill holes, the steps which comprise directing 3, ircular orifice toward the walls of the drill hole, and intermittently applying high pressure to a body of treating liquid to force same through said orifice at high velocity, whereby a plurality of vortices are formed which move through the liquid in the drill hole to the walls of the drill hole.

MAXWELL H. HALDERSON. WILLIAM L. MORRIS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 700,328 Hendershot May 20, 1902 708,897 Meals Sept. 9, 1902 2,001,350 Mills May 14, 1935 2,016,825 Trotter et al Oct. 8, 1935 2,075,755 Anderson Mar. 30, 1937 2,117,898 McDowell May 17, 1938 2,134,320 Taylor Oct. 25, 1938 2,231,666 Golber Feb. 11, 1941 2,258,001 Chamberlain Oct. 7, 1941 2,290,502 Squires July 21, 1942 2,327,051 Lyons et a1 Aug. 17, 1943 2,435,527 Arpin Feb. 3, 1948 OTHER, REFERENCES Air Conditioning and Engineering, edited by Engineering Staff of American Blower Corp. and Canadian Sirocco Co. Ltd., pp. 27-33, pp. 27 and 33 relied on.

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