US1959368A - Means and method of centrally positioning alpha tube within an open well hole - Google Patents

Description

May 22, 1934. c. B. KENNEDYE 1,959,368

MEANS AND METHOD OF CENTRALLY POSITIONING A TUBE WITHIN AN OPEN WELL HOLE Original Filed 001;. 5, 1932 I III lllill [NVENTOB CHAQL E5 :BENTON mam/E0 YE A fro NE Y.

Patented May 22, 1934 UNITED STATES PATENT OFFICE MEANS AND METHOD OF CENTRALLY POSI- TIONING A TUBE WITHIN AN OPEN WELL HOLE Application October 5, 1932, Serial no. 636,280 Renewed March 7, 1934 Claims.

This invention relates to improvements in a method and means for cementing or otherwise anchoring a well casing and refersspecifically to a method of introducing Portland cement or other 5 cementitious material between a predetermined portion of the well casing and the walls of the open hole, and means associated with the casing to maintain said casing concentric with the hole during the introduction and setting of the cementitious material.

The objects, utility and advantages of my invention will be apparent from the accompanying drawing and following detail description.

In the drawing, Fig. 1 is an elevational view 16 of a string of casing provided with a suitable device for carrying out my invention.

Fig. 2 is a detail elevational view of a portion of the well casing shown in Fig. 1. v

Fig. 3 is a sectional view taken on line 3-3 of Fig. 2.

Fig. 4 is a sectional view taken on the line 4---4 of Fig. 2.

Referring in detail to the drawing, 1 indicates a fragmentary portion of a section of well casing positioned within open hole 2. In drilling oil wells, for instance, it is common practice to insert a 7-inch (outside diameter) casing, for example, within a 9% inch hole, or an 8 inch casing inside of an 11 inch hole. ,However, it is to be understood that I do not wish to be limited to the particular size or sizes of pipe or hole with which my invention may be used.

After the hole 2 is initially drilled, it is the practice to insert into the hole one or more casings,

depending upon the depth of the hole. To support said casing or casings within the hole, the

space between the inner walls of the hole and the outer surface of the casing is filled with cementitious material which, in addition to supporting 40 the casing prevents the encroachment of water and, hence, preserves the life of the casing. In

cementing the casing in place, it is advantageous to have the casing completely surrounded with cement, in other words, it is desirable that the casing be coaxially disposed with respect to the hole.

As a feature of my invention, I my position a spacing member upon predetermined portions of the exterior surface of the casing whereby said surface may be prevented from bodily contacting the walls of the hole. The spacing member may take the form of a live rubber or composition band 3 which may spirally encircle the casing 1 for a predetermined portion of its length. For in- 65 stance, the band may extend upwardly a distance of twenty-five feet or more above the point of introduction of the cementitious material. Ac-' cording to common practice, to cement a casing in place, the cement is passed downwardly through the casing under pressure and forced upwardly between the outer surface of the casing and the inner walls of the hole. By the provision of the spirally positioned band 3 a spiral path is defined which may serve as a passageway for the upwardly passing cement. In passing upwardly in this manner the cement must of necessity travel around the casing and, hence, a substantially equal quantity thereof will be positioned upon each side of the casing, consequently tending to centralize the casing. It can readily be seen that, if the cement were free to pass upwardly without the guidance of the spiral path,

it may tend to mass upon one side or other of the casing and maintain the casing in contact at its opposite side with the inner walls of the hole. This action may be cumulative and may even tend to displace a normally centralized casing. However, by the provision of the spiral band 3 and by imparting swirling or helical motion to the rising cement a casing normally disposed eccentric with so respect to the hole will tend to be centralized whereas a casing normally centralized will be maintained in coaxial position.

To maintain the spiral band 3 in position, I may pass metallic straps 4 through apertures 5 provided at spaced intervals along the length of the band 3. Said straps may then be fastened transversely around the casing in any conventional manner so as to maintain band 3 in spiral position upon the casing. Of course, it is to be understood that, other means may be provided for maintaining the band 3 in place upon the casing. Hence, I do not wish to be limited to the precise structure shown inasmuch as my invention broadly contemplates spacing the casing 95 within the hole in substantially concentric position with the hole and cementing the same therein.

It is to be understood, of course, that my invention may be used wherever it may be desirable to maintain a pipe, tube or casing concentric with the axis of a hole. For instance, my invention may be utilized in conjunction with the drilling of wells, wherein the drill pipe (not shown) may carry a helical spacing element similar to member 3 which may tend to prevent contact between the pipe proper and the walls of the hole being 1 drilled. By this provision, the slush water being discharged. at the bit (not shown) passes upwardly between the surface of the pipe and the 110 walls of the hole along a helical passageway defined by the spacing member, the surface of the pipe and the walls of the hole. By confining the upwardly passing water to said helical path, the velocity of the water is increased in a degree dependent upon the pitch of the helix and consequently a more eflicient washing away of the cuttings results, in addition to the tendency of the swirling water to maintain the drill pipe in coaxial position with respect to the hole.

I claim as my invention:

1. A method of cementing a. well casing within an open hole which comprises passing a plastic cementitious material downwardly through the casing under superatmospheric pressure, passing said cementitious material upwardly from the bottom of the casing and positively directing said material along a spiral path around the casing between the outer surface of the casing and the walls of the hole for at least one complete revolution.

2. A method of cementinga well casing within and substantially coaxially with an open hole which comprises positioning a casing within an open hole and mechanically spacing said casing from the walls of the hole, passing a plastic cementitious material downwardly through the casing under superatmospheric pressure, passing said cementitious material upwardly from the bottom'of the casing and positively directing said 'material along a. spiral path around the casing between the outer surface of the casing and the walls of the hole for at least the circumferential length of the casing.

,3. In combination with a well casing, a strip of resilient material wound spirally about the casing for a plurality of revolutions, and means for securing the strip to the casing in such position, comprising metallic straps encircling the casing at spaced intervals, said straps passing through the body of said resilient strip.

4. In combination, a well casing, a strip of resilient material wound, spirally around said casing throughout a predetermined portion of its length defining a spiral channel upon the face of the casing, a plurality of metallic straps embracing said casing at spaced intervals throughout said predetermined portion of the length of the casing, said strapspassing through apertures provided in said resilient strip.

5. In combination with a well casing, a continuous rubber strip wound spirally about the casing for a plurality of revolutions to center the casing within a well hole, and means for securing the strip to the casing in such spiral position.

CHARLES BENTON KENNEDYE.

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