US2117898A - Apparatus for cementing wells - Google Patents

Description

Filed Sept. 9, 1937 Patented May 17, 1938 PATENT OFFICE APPARATUS FOR CEMENTING WELLS Charles 0. McDowell, Fairmont, W. Va.

Application September 9, 1937, Serial No. 163,049

4 Claims.

This invention relates to apparatus for cementing wells.

The primary object of the invention is to provide an eflicient and inexpensive device whereby 5 a quick-setting ementitious material in a liquid or semi-liquid state may be lowered into an oil or gas well to a point where the wall of the well has caved in, the cement being released and discharged from the device under pressure at the 10 point of cave-in so that the 'cement may be sprayed therefrom, impinge and become lodged against the caving surface to a predetermined, substantially uniform, thickness for forming a lining for the ruptured or slipping portion which, 15 when hardened or set, serves as a lining to prevent further caving or inward movement of the earth.

With this and other objects in view, the invention resides in certain novel features of construcgo tion, operation and arrangement of parts which will hereinafter be fully described, reference being had to the accompanying drawing, in which- Figure l is a partial vertical sectional view of a well illustrating the device positioned in a cave- Figure 2 is an enlarged side elevational view of the device, parts being broken away in order to depict interior construction and arrangement of parts; and-- Figure 3 is an enlarged fragmentary detail view depicting the latch and latch release means.

Referring to said drawing, the reference numeral l designates a cylindrical casing having a tapered closed bottom 2 and whose upper threada length of pipe or a well bailer 3 by means of the coupling 4, the pipe 3, which may be of any predetermined length or capacity, serving as a hopper or reservoir for containing the supply or 40 charge of cementitious material. A pivoted car- I rying bail 5 is attached to the upper open end of the hopper 3 and is designed to receive a length of cable (not shown) by means of which the apparatus is raised and lowered in the well 45 casing 8. n

An inverted conical bottom I is provided for the cement reservoir, the same being provided adjacent the upper end of the casing and having a port provided in its extreme bottom end. Lateral discharge ports 8 are provided in the casing directly beneath the bottom I at diametrically opposite points of the casing I, although the number and position of said ports 8 may be varied as desired.

A vertically slidable tappet valve 9 is designed to register with the under side of the port of the reservoir bottom 1, the valve stem It! being received in bearing apertures provided in spaced 50 plates II and 12 located interiorly of the casing ed end is designed to be detachably connected to I I. A disc-like plate I3 is permanently attached to the lower end of the valve stem 10.

A fixed bracket [5 extends transversely of the casing l at a spaced distance beneath the valve stem l and has pivoted thereto an inverted L- shaped lever I 6, the lower end being bifurcated and carrying on a shaft H a freely rotatable wheel l8. A pin 33 protrudes outwardly from each of the opposite faces of the wheel for a purpose to be hereinafter explained.

A small segmental portion of the wheel 18 extends outwardly of the casing I through a rectangular opening l9 provided in the casing. The upper end of the lever has provided therein an adjusting set screw 20 which, when the wheel I8 is in the position depicted in full lines in Fig.

1 of the drawing, underlies the valve stem plate l3 so as to maintain the valve in closing relation to the port. A small retractile coil spring 2| is interposed between and attached to the bracket I5 and lever l6, while a compression spring 22 encircles the valve stem l0 and is interposed between the underside of the plate II and a member 23 fixed to the valve stem.

Latch mechanism for maintaining the valve 9 25 in closed position is pivoted to the bracket l5. The latch mechanism consists of a two-piece lever 25 whoseabutting ends are joined together by a flat spring 26, the upper section of the lever having a notch 38 adapted to receive therein the valve stem plate l3 and thereby support the valve 9 in closed position and being maintained in valve closing position by the provision of a spring catch 3|. The bottom portion of the lower section of the lever 25 is bifurcated and straddles the wheel l8 when the latter occupies the full line position shown in Fig. 1, the extreme lower ends of the bifurcated portion terminating in an inclined angle.

Preparatory to using the device, the valve 9 is 40 locked in the position shown in the drawing and a quantity of an appropriate cement-itious material in a suitable liquid or semi-liquid state is introduced into the reservoir 3 and thereafter the device is lowered into the well by the cable attached to the ball 5 until the spraying device reaches the point of cave-in 35. As the device is being lowered into the well, that portion of the wheel l8 protruding outwardly of the casing I through the opening l9 frictionally engages the well casing 6 causing counterclockwise rotation of the wheel I8. With each complete revolution of said wheel its pins 33 will slightly engage the lower portion of the latch lever 25, but, due to the flexibility afforded by the spring connecting joint 26, as well as the inclined terminal end of the lever 25, the lever 25 will be permitted to be forcibly moved by the pins 33 in the same direction as the wheel rotation a sufficient dis.-

changed to clockwise direction.

tance to permit passage of the pins 33 without disturbing the valve latch.

Upon reaching the point of cave-in 35, the device is elevated a short distance in the well casing 6 so that rotation of the wheel I8 is During such rotation, the pins 33 will engage the side of the lever 25 opposite that engaged during counterclockwise rotation. This results in movement of both sections of the lever 25 as a unit resulting in disengagement of the valve latch 30 against the tension or resistance offered by the spring catch 3|.

Following release of the valve latch, the device is lowered into the cave-in area 35. At this point the wheel I8 is no longer in contact with the well casing 6 and the retractile coil spring 2| acting on the lever l6 forces the wheel l8 and the lower portion of the lever l6 outwardly of the casing I through the opening l9. Obviously, therefore, no support is now afforded the valve 9 and the compression spring 22, together with the weight of the imposed cement charge, forces the valve 9 to open position and the cementitious material gravitates from the reservoir and is discharged laterally from the device through the ports 8. The imposed weight of the cement in the reservoir results in considerable pressure at the discharge ports 8 so that the cement is sprayed with considerable pressure or velocity against the surface of the cave-in and tenaciously adheres thereto for effecting a lining of cement and preventing further slippage of the earth. As hereinbefore stated, the cement is preferably quick setting so that it hardens rapidly.

The device is preferably rotated and vertically reciprocated in the cave-in by means of the v suspending cable in order that the entire surface may receive an adequate coating of cement.

After a sufficient coating of cement is applied, the device is upwardly withdrawn from the well. Upon again entering the well casing, the wheel l8 will be pushed into its casing enclosed position moving the lever l6 about its pivot to elevate the valve 9 to closed position. Thus, no cement 'can be discharged from the device while the same is being removed from the well.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

What is claimed is:

1. In a device for cementing wells, a cylindrical casing having an opening in its wall, a reservoir for a quantity of cementitious material, a bottom for said reservoir having a discharge opening therein, lateral discharge ports in said casing beneath said reservoir bottom, a valve operable in said reservoir opening, pivoted means maintaining said valve closed while said means are confined within said casing by pressure exerted thereon by the casing of the well to be cemented, said means being forced outwardly of said casing through its wall opening upon cessation of the well casing pressure for releasing said valve and permit of its opening to permit the cementitious material to gravitate from said reservoir through said bottom opening and outward of the casing through the lateral discharge ports.

2. In a device for cementing wells, a cylindrical casing having an opening in its'wall, a reservoir for a quantity of cementitious material, a bottom for said reservoir having a discharge opening therein, lateral discharge ports in said casing beneath said reservoir bottom, a valve operable in said reservoir opening, pivoted means maintaining said valve closed while said means are confined within said casing by pressure exerted thereon by the casing of the well to be cemented, said means being forced outwardly of said casing'through its wall opening upon cessation of the well casing pressure for releasing said valve and permit of its opening to permit the cementitious material to gravitate from said reservoir through said bottom opening and outward of the casing through the lateral discharge ports, and releasable latch means for locking said valve in closed position.

3. In a device for cementing wells, a cylindrical casing having an opening in its wall, a reservoir for a quantity of cementitious material, a bottom for said reservoir having a discharge opening therein, lateral discharge ports in said casing beneath said reservoir bottom, a valve operable in said reservoir opening, a pivoted valve supporting lever controlling the operation of said valve, a wheel, carried 'by the valve supporting lever and having a segmental portion protruding outwardly of the casing through its opening and frictionally engageable with the casing of a well to be cemented, said lever supporting said valve in closed position while said wheel is in contact with said well casing, said wheel being free to move outwardly of said casing through its wall opening when said wheel is out of well casing contracting relation for moving said lever from valve supporting relation and permitting said valve to move to its open position to permit discharge of the material from said reservoir through said bottom opening and outward of the casing through the lateral discharge ports.

4. In a device for cementing wells, a cylindrical casing having an opening in its wall, a reservoir for a quantity of cementitious material, a bottom for said reservoir having a discharge opening therein, lateral discharge ports in said casing beneath said reservoir bottom, a valve operable in said reservoir opening, a pivoted valve supporting lever controlling the operation of said valve, a wheel carried by the valve supporting lever and having a segmental portion protruding outwardly of the casing through its opening and frictionally engageable with the casing of a well to be cemented, said lever supporting said valve in closed position while said wheel is in contact with said well casing, said wheel being free to move outwardly of said casing through its wall opening when said wheel is out of well casing contacting relation for moving said lever from valve supporting relation and permitting said valve to move to its open position to permit discharge of the material from said reservoir through said bottom opening and outward of the casing through the lateral discharge ports, and latch means engageable with said valve for maintaining the valve' in closed position and adapted to be disengaged by contact with a protuberance borne by said wheel.

CHARLES O. MCDOWELL.

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