US3012623A

US3012623A - Wellpoint

Info

Publication number: US3012623A
Application number: US720287A
Authority: US
Inventors: Joseph P Powers
Original assignee: Moretrench Corp
Current assignee: Moretrench Corp
Priority date: 1958-03-10
Filing date: 1958-03-10
Publication date: 1961-12-12
Anticipated expiration: 1978-12-12

Description

J. P. POWERS 3,012,623

WELLPOINT Filed March 10, 1958 Dec. 12, 1961 TECH.

L50 lNVENTOR k \fOJEPH Po WEAJ United States atent 3,012,623 WELLPOINT Joseph P. Powers, Boonton, N.J., assignor to Moretrench Corporation, Rockaway, NIL, a corporation of New Jersey Filed Mar. 10, 1958, Ser. No. 72tl,287 4 Claims. (Cl. 175-318) This invention relates to wellpoints; and more particularly to improved valve means for controlling the flow of water therethrough.

A wellpoint is a pipe device which is inserted into the ground to dewater the soil about it. Wellpoints are normally used where an excavation is to be made and the water level of the soil is above the elevation of the bottom of the area to be excavated.

A wellpoint consists of a center tube or pipe with a coupling at its upper end to which a riser pipe is attached. A jetting tip is fitted to the bot-tom end of this center pipe and an open mesh screen cylinder surrounds the center pipe and is positioned between the coupling and the jetting tip.

A wellpoint is sunk into the ground by connecting the riser to a pressurized source of water. A stream of water is forced through the riser pipe and into the wellpoint. In a wellpoint of typical construction, the water then flows through a ball valve and is jetted out through the jetting tip. As the water leaves the jetting tip it erodes away the soil about it; thus providing a hole beneath the wellpoint into which the wellpoint sinks. This is continued until a desired depth is reached at which point the supply of jetting water is shut oif.

The riser pipe is then connected to a header pipe which is connected to a suction source, such as a vacuum or suction pump, and a suction is set up within the wellpoint. A combination of the ball valve buoyancy and the suction causes the ball valve to close the passageway through the jetting tip. With this jet-ting tip closed, the suction pulls the water which is in the soil surrounding the wellpoint through the mesh screen, into the center pipe, and into the riser and header from which it is discharged. In actual commercial operations a centrifugal pump continuously primed by a positive displacement vacuum pump is used.

Prior to the present invention various types of ball valve assemblies were used in wellpoints to control the flow of water through the jetting tip. However, these have suifered from many shortcomings and have not been fully satisfactory.

Previous valves were not arranged to insure that the flow of water through the tip would be fairly smooth and not unduly turbulent. This turbulence was caused by the fact that the ball valve was eccentrically positioned, thus causing an unbalanced condition in the passageway of the jetting tip.

Accordingly, it is an object of the Present invention to provide a simple and efficient ball valve assembly for wellpoints. It is another object to provide such an assembly which improves the flow of water through the jetting tip. It is a further object to provide a ball valve assembly which is easy to install and maintain. It is still another object to provide an assembly wherein the ball valve is positively positioned and held in the center of the stream of water. It is a still further object to provide a ball valve assembly which is securely held in place within the jetting tip. Another object is to provide a ball valve assembly which provides a symmetrical annular passageway for the water flowing through the jetting tip.

In this specification and the accompanying drawings a prefered embodiment of the present invention in wellpoints is shown and described. It is to be understood that this is not intended to be exhaustive nor a limiting ice of the invention, but, on the contrary, is given for the purpose of illustration in order that others skilled in the art may fully understand the invention, its principles and the manner of. carrying it out.

In the drawings:

FIGURE 1 is a front view of a wellpoint;

FIGURE 2 is a sectional view of the wellpoint in the direction of arrows 2-2 of FIGURE 1;

FIGURE 3 is a sectional view of the ring valve of the wellpoint in the direction of arrows 33 of FIGURES l and 2; this view extending downwardly only to the bottom of the seat for the ball valve;

FIGURE 4 is a front view of a basket for holding the ball valve centered within the jetting tip; this basket being shown in relation to the seat for the ball valve and the wall sections of the wellpoint; and

FIGURE 5 is a top view of the basket shown in FIG- URE 4.

Referring to FIGURE 1, a complet wellpoint 10 is shown connected to a riser pipe 12. The major components of this wellpoint 10 are the jetting tip 14, the cylinder screen 16 and the upper coupling 18, and as shown in FIGURE 2, the center pipe 20, the ball valve assembly 22 and the ring valve 24.

As stated above, when the wellpoint is being sunk into the ground water enters the riser pipe 12, flows downward through the center pipe 20, through the ball valve assembly 22 and out the bottom of the jetting tip 14.

The ball valve assembly 22 shown in FIGURE 2 comprises a ball valve 26, a retainer basket 28, a valve seat 30 and a shoulder ring 32 for holding the valve seat 34} in position above the retainer basket 28. The ball valve 26 has a wooden center 33 which gives it buoyancy in water while assuring a true spherical shape. The wooden center is encased in a tough elastic coating 35 which protects the ball from wear and tear and helps to achieve a close fit between the ball valve 26 and the valve seat 30.

The valve seat 30 is a fiat disc which is set transversely within the jetting tip 14. This seat 30 has a central opening 34 which has a smaller diameter than that of the ball valve 26. When suction is applied to the center pipe 20 the ball valve 26 is pulled into the opening 34, thus closing off the lower portion of the jetting tip 14 from the center pipe 20. When jetting water is forced through the center pipe 20, the ball valve 26 rests in the retainer basket '28, which serves as a cradle support for the ball valve. The retainer basket 28 is placed so that the ball valve 26 when against the bottom of the basket is substantially centered on the vertical axis of the wellpoint. Basket 28 is comprised of four crossed arms 38,

4t

42 and 44 and an automatic centering action is provided by virtue of the fact that the

arms

38, 40, 42 and 44 slope inwardly toward the lower end of the basket. which, as shown in FIGURE 2, is shaped to conform exactly to the contour of the ball valve 26. Thus, the ball valve 26, when cradled in the basket 28. provides a symmetrical, annular opening 37 in the jetting tip 14.

This annular opening 37 and the spherical shape of the ball valve reduces the amount of turbulence that would otherwise occur in the jetting water when the wellpoint is being sunk into the ground. The annular opening 37 and the spherical shape of the ball valve 26 tend to stream- 7 The valve seat 30 is held in position by a novel arrangement. A series of vertical ribs 36 are spaced about the bottom portion of the center pipe and, as shown in FIGURE 3, tack welded to the inner wall surface of the jetting tip 14 and to the outer wall surface of the center pipe 20. The shoulder ring 32 is then set within the jetting tip to about against these ribs 36. The valve seat is placed against ring 32 and held in this position by the upper portion of the retainer basket 28.

The retainer basket 28, as shown in greater detail in FIGURES 4 and 5, is comprised of two separate lengths of wire which are crossed at 51 to form the four

cradle arms

38, 40, 42 and 44. The two arms formed from each length of wire are substantially similar and the length of

wire forming arms

38 and 40 is dimpled or crimped at 51 so as to accommodate the crossing wire of

arms

42 and 44, thus insuring that the inside surface of the four arms form a spherical landing for the ball valve 26.

Arms

38 and 40 have short, hooked ends 46 which are inserted into holes 48 in the wall of the jetting tip 14-. The

other arms

42 and 44 are also bent at their ends 50, and these bent ends bear against the lower face of the valve seat 30.

The normal, relaxed positions of the

arms

38, 40, 42 and 44 are shown by the phantom lines in FIGURES 4 and 5. In order to insert the retainer basket 28 into the jetting tip 14, it is necessary to compress the

arms

38, 40, 42 and 44 towards the center of the basket 28. After being inserted into the jetting tip 14 by placing ends 46 in the holes 48 and by pressing the bent ends 50 against the valve seat 30, the

arms

38, 40, 42 and 44 are sufiiciently resilient to impose a substantial upward force against the valve seat 30 to maintain it in proper position against the lower end of the ring 32.

The outfiowing water in the jet stream tends to carry the ball valve 26 with it and would do so except for the basket 28. The pressure of this outward flow of water on the ball valve 26 is transmitted to the

arms

38, 40, 42 and 44 of the retainer basket 23, and the basket 28 would also be dislodged from the jetting tip except for engagement of the hooked ends 46 in the holes 48. To insure that the hooked ends 46 will not slip out of the holes 48, these ends 46 are preferably inclined downwardly toward their outer ends to enhance their anchorage in the holes against the downwardly applied force.

When jetting water is being pumped through the center pipe 20 and out the jetting tip 14, it is desirable to have most of this water flow through the jetting tip 14. To

insure this result, a flat ring valve 24 is provided on top of the valve seat 30 and within the shoulder ring 32. This ring valve 24 is freely slidable and loosely fitting within the shoulder ring 32. As jetting water passes through the opening 34 in the valve seat 30, a slight turbulence and back wash is created at that point since the diameter of opening 34 is slightly less than the inside diameter of the center pipe 20. This turbulence and back wash lift up the ring valve 24 and hold it against the spacer ribs 36, thus almost completely sealing off the annular space between the outer wall of the center pipe 20 and the inner wall of the shoulder ring 32. Therefore, most of the jetting water is confined within the jetting tip 14 and forced out of the tip in the form of a jet stream. However, due to the loose fit of the ring valve 24 within the shoulder ring 32, a small volume of the jetting water flows upwardly between the ribs 36 and out through the cylinder screen 16. This slight back wash has a beneficial efiect inasmuch, as it helps to keep the screen 16 clear while sinking the wellpoint 10 into the ground.

When the wellpoint is sunk to the proper elevation, and the jetting water is turned 01?, the ring valve 24 drops back onto the valve seat 30. The water in the soil causes the ball valve 26 to float upwardly against the valve seat 30 and close the opening 34 therein. When suction is applied, the ball valve 26 is sucked even more tightly against the valve seat. This suction causes water in the soil surrounding the wellpoint 10 to be pulled through the cylinder screen 16, between the ribs 36 and into the center pipe 20. From there it passes into the riser pipe 12 and then into a header from which it is discharged.

From the foregoing description it will be appreciated that the present invention provides a practical wellpoint valve means which insures improved jetting action and increased efiiciency in sinking the wellpoint. It will thus be appreciated that the present invention accomplishes the aforementioned and other advantageous objects. However, it should also be emphasized that the foregoing description of the particular embodiment of the present invention which is shown in the accompanying drawings is intended to be merely illustrative of the invention and not restrictive of the scope of the invention which is defined in the following claims:

I claim:

1. In a wellpoint of the type described, a jetting tip assembly comprising a jetting tip with an opening longitudinally therethrough, a valve seat transversely positioned in place in said tip, a ball valve, and a valve retainer basket fixedly engaged within and immovably secured to said tip by holding means, said retainer basket thereby being held securely and immovably in place beneath said valve seat and said ball valve being movably located within said basket and beneath said valve seat.

2. In a wellpoint of the type described, a jetting tip assembly according to claim 1, wherein said retainer basket is tapered towards the longitudinal axis of the jetting top and depends downwardly from said valve seat so that said ball valve is centered substantially about the longitudinal axis of said wellpoint when fluid is discharged outwardly through said jetting tip and past said valve seat and said ball valve, the position of said ball valve providing a symmetrical passageway through said tip whereby the jet stream of fiuid is centered substantially directly beneath the wellpoint.

3. In a wellpoint of the type described, a ball valve assembly set within a jetting tip and comprising a ball valve, guide and support members for said ball valve, a valve seat for said ball valve, and rigidly positioned upper support means set above said valve seat, said valve seat being positioned below but against said upper support means and above said ball valve and above said guide and support members, the upper portions of said guide members being adjacent to the walls of said jetting tip and said valve seat, at least two of said members having hooked ends in their upper portions and said hooked ends being fitted into openings in said jetting tip, and the upper portion of at least two of said members in contact with said valve seat whereby said seat is fixedly positioned between said members and said upper support means, said guide members extending downwardly from said valve seat and converging to form a bottom support for said ball valve below and away from said valve seat.

4. A wellpoint of the type described, a jetting tip assembly according to claim 1 wherein said retainer basket is comprised of a plurality of arms which taper towards the longitudinal axis of the jetting top and depend down wardly from said valve seat.

References Cited in the file of this patent UNITED STATES PATENTS 369,032 Richards Aug. 30, 1887 411,660 Hart Sept. 24, 1889 672,097 Eastman Apr. 16, 1901 827,190 Stebbens July 31, 1906 1,596,520 Eskholrne et al Aug. 17, 1926 2,136,015 Nicks Nov. 8, 1938 2,198,573 Davis et a1. Aug. 23, 1940 2,640,545 Share June 2, 1953