US2150311A - Wash-down and cementing shoe for well casings - Google Patents

Description

March 14, 1939. R Q BAKER 2,150,311

WASH-DOWN AND CEMENTING SHOE FOR WELL CASINGS Filed Dec. 12, 1938 INVENTOQR BY aa am ATTORNEY Patented Mar. 14-, 1939 UNITED STATES PATENT OFFICE WASH-DOWN AND CEMENTING SHOE FOR WELL CASINGS Application December 12, 1938, Serial No. 245,237

4 Claims.

This invention relates to devices and apparatus used during the casing and cementing of oil wells.

It is the principal object of the present invention to provide an improved wash-down and cementing shoe for oil well casings which is 50 constructed that it may be employed in conditioning a well bore and in efiectively washing out formation bridges during the casing of a well bore,

and which may be employed in cementing the casing in the bore.

In practicing my invention, I provide a casing shoe which is formed with a series of baffie ports at its periphery which are so directed that a series of downwardly projecting jets are created when fluid is pumped under pressure downwardly through the shoe, which jets are so directed that they will cut away the sides of a bridge or obstruction in advance of the shoe, while the casing is being lowered in the hole, and thereby facilitate the casing of a well. Likewise, these jets will act during the lowering of the casing in the well to condition the hole. After the casing has been positioned, cement may be ejected through these baflie ports, and inasmuch as they are distributed about the circumference of the shoe, the cement will discharge evenly about the entire perimeter of the shoe so as to insure distribution of the cement entirely around the lower 'end of the casing.

One form which the invention may assume is exemplified in the following description and illustrated by way of example in the accompanying drawing, in which:

Fig. 1 is a view in vertical section through a device showing the preferred form of my invention.

Fig. 2 is a side elevation of the same.

Fig. 3 is a transverse sectional view taken on line IIIHI of Fig. 1.

Referring more particularly to the accompanying drawing, l0 indicates a well bore and l l a casing being lowered thereinto. At the lower end of this casing is a casing shoe (2 having a plug Id of cementitious material cast therein to form a guide 15. While in this instance the plug 14 is shown as being of cementitious material, it may be formed of any suitable material and connected to the casing shoe l2 in any suitable man- 50 nor. This plug has a central passageway l6 formed therethrough as in usual practice.

In the present instance I have shown the casing shoe as being what is termed in the art a guide shoe, although it is readily apparent that it may be a float shoe. That is to say, a valve structure may be mounted in the shoe above the guide plug l4 so as to enable the casing to be floated in place in the well bore.

Extending laterally from the central and longitudinally directed passageway I6 are four ports I! which extend outwardly through the casing shoe l2. These ports are arranged at equal distances apart around the circumference of the shoe, and although I have shown four, it can be readily understood that more or less than that number may be employed if so desired.

1 In alignment with each port II, the outer surface of the casing shoe [2 is formed with an elongated groove I8 which is milled or otherwise formed in the casing shoe, but which extends short of the inner circumference of the casing shoe so that the port ll forms a communication between the groove (8 and the interior of the shoe. The bottom of each of said grooves l8 tapers outwardly from the ports I! to the outer perimeter of the shoe as illustrated in the drawing. Overlying each port is a baffle plate l9 which covers the groove at the perimeter of the shoe and spaced from the bottom of the groove. The lower end of the bafiie plate 19 extends short of the lower end of the groove so as to transform the same into a downwardly and slightly outwardly directed passageway. Although separate bafiles H) are shown for each port, it is obvious to those skilled in the art that any suitable baflling means may be provided to accomplish this result.

It will be noticed that the grooves are generally vertically positioned with respect to the longitudinal axis of the shoe, but that they are slightly inclined to the vertical so as to give any fluid passing downwardly through the passageways a slight whirling motion with respect to the shoe. I have found that this action not only creates an ideal washing action for cutting away the sides of a formation bridge in a well bore, but also in conditioning the walls of the hole during the casing thereof. Further, that after the casing is lowered into position in the bore and cement is ejected downwardly through the 4 casing, it will discharge from these ports with a. slight whirling action sufficient to insure that the cement will be evenly distributed around the shoe and thereby prevent channeling.

It should be pointed out here that the total area of the ports I1 is such with relation to the central passageway l6 and to the diameter of the casing that when fluid is pumped downwardly through the casing under the ordinary pressures, that forceful jets of fluid will be directed outwardly and downwardly through the passageways formed by the grooves l8 and the baflle plates I9 much in the manner shown by the arrows in Fig. 1.

In operation of the device, it is constructed as illustrated and assembled on the lower end of the casing. In running-in the casing, if the hole is bridged, the hydraulic or downward jetting action of the fluid discharging from the grooves or passageways [8 outs away the sides of the bridge and the formation is readily circulated up the hole as it is removed. At the same time that the bridge is disintegrated and washed away, the casing is lowered through a free hole without danger of being stuck. The direction of flow out of the ports is essentially downward, but there is enough inclination of the hydraulic streams to produce a whirling motion that facilitates circulation and completely washes away the obstruction.

I also desire to point out that by the fluid action emerging from the jets o-r passageways l8, the sides of the hole may be conditioned as the casing is being run-in, and that after the casing has reached its proper point in the bore, the ports I! and the jets 18 may be advantageously used for the discharge of the cement slurry utilized to cement the casing in the bore. Due to the slight inclination of the ports; the cement will be discharged in a slightly whirling motion which insures that it will be distributed equally around the casing and prevent channeling.

It is obvious from the foregoing that by means of my invention, I have provided a device which will facilitate the running of a easing into a hole where bridges or other formation obstructions may be encountered. The use of such devices will assure that the casing will reach bottom safely and that by means of the side washing action, the hazard of freezing of the casing in the hole will be reduced to a minimum.

While I have shown the preferred form of my invention,- it is to be understood that various changes may be made in its construction by those skilled in the art without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. A wash-down shoe for well casings comprising a tubular cylindrical member adapted to be connected to the lower end of a well casing, a plurality of nozzles formed about the circumference of said shoe at spaced distances apart, each of' said nozzles comprising an elongated groove formed in the outer surface of said cylindrical member and arranged generally vertically with respect to the same and communieating with the interior of the shoe, baflie means secured to the shoe and overlying the upper portions of said grooves so that fluid discharged through said grooves will be directed downwardly with respect to the shoe.

2. A wash-down shoe for well casings comprising a tubular cylindrical member adapted to be. connected to a well casing, a plurality of nozzles formed in said shoe at spaced distances about the perimeter thereof, each of said nozzles comprising a groove formed in the outer surface of said cylindrical member at a slight angle to the vertical and communicating with the interior of the shoe, and baffie means fixed to the shoe and overlying the upper portions of said grooves so that fluid discharging through said nozzles will be directed downwardly at a slight angle to the vertical.

3. A wash-down shoe for well casings comprising a tubular cylindrical member adapted to be connected to the lower end of a well casing, a plurality of nozzles formed in said shoe at spaced distances about the perimeter thereof, each of said nozzles comprising an elongated groove formed in the outer surface of said cylindrical member at a slight angle to the vertical and having its bottom tapering outwardly to- .ward the lower end until it intersects the outer perimeter of the shoe, said shoe having ports forming a communication between said grooves and the interior of the shoe at a spaced point above the lower end of the groove, and fixed bafile means at the exterior of the shoe overlying and enclosing the upper portions of said grooves and overlying said ports but extending short of the lower ends of the grooves whereby fluid discharged through said ports will be directed downwardly at a slight angle to the vertical.

4. A wash-down shoe for well casings comprising a tubular cylindrical member adapted to be connected to the lower end of a string of .well casing, a plug secured in said shoe and having a longitudinal passageway formed longitudinally and centrally therethrough, radial ports formed in said shoe above the lower end of the plug at spaced distances apart circum- 'ferentially of the shoe, said cylindrical member being formed with an elongated groove in alignment with each port, said grooves being disposed at the exterior of the shoe and being disposed at a slight angle to the vertical, said grooves being positioned with respect to said ports so that the latter communicate therewith at a point spaced from the lower ends of 'said grooves, the bottom of said grooves tapering outwardly from said ports toward their lower ends until they intersect the outer perimeter of the shoe, baflle means secured substantially at the perimeter of the shoe and overlying the grooves and said ports but extending short of the bottom of the grooves, whereby fluid pumped downwardly through the shoe will be forced in forceful jets downwardly at the perimeter of the shoe at a slight angle to the vertical.

' REUBEN C. BAKER.

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