US1527749A - Well-cementing plug - Google Patents

Description

`of cementing a well as an oil well;

Patented Feb. 24, 1925.

.UNITED STATES EDWARD F. RAYMOND, 0F SANTA FE SPRINGS, CALIFORNIA.

WELL-CEMENTING PLUG.

Application led March 24, 1924. Serial No. 701,467.

To all whom t may concern.'

Be it known that I, EDWARD F. RAYMOND, a citizen of the United States, and a resident of the city of Santa Fe Springs, county of Los Angeles, State of California, have invented new and useful Improvements in Vell-Cementing Plugs, of which the following is aspecification.

My invention pertains to a well plug adapted to follow the cement in the' process Its objects are to provide a plug constructed of material which will oder the least possible obstacle to drilling after the cement formation has hardened; that is provided with suilicient buoyancy for the purposes desired; that contains no vegetable-fibre or other material which l'ilight clog the drill pipe and pump screen when drilled out; that is practically frictionless when advancing into the hole; and that is readily drilled and ground to powder by the well tools and removed as dbris with the mud and sediment in the ordinary manner.

I attain these objects among others by the novel provision, formation, construction, association and combination of parts and members as shown in the accompanying drawings, in which* Figure l is a general view in side elevation of the complete plug.

Figure 2 is a longitudinal cross section of the complete plug.

y plug has been especially designed for use in drilling and cemcnting of oil Wells, and I have herein limited my description and explanation to its application in that line of business.

Plugs adapted to part the cement and mud inthe process of cementing oil wells at the present time are commonly made of wood and provided with a rubber sleeve at its lower or entering end to serve as a. seal, and a libre cap nailed to the upper end upon which `pressure of the mud above is made to sink the plug. As this plug advances into the casing the wooden part swells and soon moves with great diiliculty because of the increasing friction. At the Sametime the rubber sleeve is torn and shredded by the burrs at the ends of the casing sections, the shreds being forced between the plug and casing to increase the friction as Well as to destroy .in great measure its sealing effectiveness. A further objection to .this commonly used type of plug is the fact that ground rubber. and wood fibre form with the mud a homogeneous mass that speedily clogs the drill pipe and pump screen. In this case there is no recourse except to come out Iof the hole to clean the drill pipe and screen. Further, this necessity frequently occurs for two or three days after the cement has hardened and is being drilled, the remedy being tedious and expensive.

Referring more particularly to the drawings:

1 indicates the cylindrical barrel of the plug.

2 indicates the lower or entering end of the plug, tapered to a blunt nose in the form of a truncated cone.

3 indicates a cup-shaped cap to fit into the upper end of barrel l, the sides of which are divided into multiple sections by' means of -multiple slits in the same reaching from the rim to approximate the bottom of said cap.

4 indicates a hermetically sealed metal chamber within said barrel l and positioned therein by means of rod 10 passing therethrough.

6`6 indicate the walls of said chamber 4. indicate a cement or concrete mass filling barrel l and completely surrounding chamber 4. l

8 indicates an open shallow chamber in the upper end of barrel l, adapted to form a receptacle for cap 3.

9 indicat-es a` diaphragm fitting tightly within the upper end of barrel l, adapted to form a bottom for receptacle 8, and provided with multiple perforations Sla-9 through which the concrete mass 7 7 may be poured, and aperture 9b for rod lO.

l0 indicates a rod adapted to pass a. "In *D longi- .tudinally from end toend of said barrel l and position air chamber 4 therein, provide-l with a threaded end'J adapted to receive nut 11j 3b indicates an aperture through the bottom of cap 3, through which rod 10 passes.

3c indicates a short section of a pipe adapted to be brazed at one end to bottom 8 over aperture 31 to serve as a guide for rod 10 and to iiisure the proper seating of cap 3 in cavity 8.

The function cfa well cementing plug is I to follow the concrete mixture and prevent the mud admitted above to pass andmix with the concrete. It is necessary that the plug be somewhat buoyant and sturdy llO enough to withstand great pressure. To said body; a compound filler within said provide buoyancy I have provided an herbody and surrounding said chamber; and l metically sealed air chamber 4, adapted by an automatically acting cupped cap adapted its size to offset; the specific gravity of the to fit into the upper end of said body above metal plug and its concrete content.' said iller.

In assembling, rod is passed through 2. A metallic plug of the character disair chamber 4 longitudinally and brazed closed comprising a cylindrical tubular 60 therein. The lower end of rod 10 is brazed body, one end thereof tapered to form the to the blunt nose of the barrel 2 to pofrustrum of a cone; a hermetically sealed sition air chamber 4. Diaphragm 9 is then air chamber positioned in approximately positioned somewhat above the top of chamthe center of said body by means of a metal ber 4, rod k,10 passing through the center rod passing longitudinally therethrough aperture 3b therein, and ixed by brazin and fixed against lateral movement within or soldering. The concrete mixture T-g said body; a composition filler within saidis then poured through perforations 9**--9a body and surrounding said air chamber; until the cavity of the barrel is completely the upper portion of the walls of said body filled. Cap 3 is then slipped over rod 10 forming a receptacleabove said filler; and 70 into receptacle 8 and nut, 11 threaded onto a cupped cap adapted to tit into said the projecting threaded end of rod 10 receptacle. Y against the free end of pipe 3. Sections 3`. A metallic plug of the character dis- 3"--3a are slightly flared somewhat and the closed, vcomprising a cylindrical tubular plug is ready for insertion into thecasing. body; an air chamber positioned in approxi- I prefer to make this plug of tlat metal mately the center of said body; a metal rod copper sheeting of rather thin gauge, the passing longitudinally through said chamoutside diameter of barrel 1 being approxiber adapted to position said chamber and mately the same as the inside diameter of provided with `a threaded end adapted to the casing of the well. Flaring of the direceive'a nut thereon; a filler within said so vided sections 3**--3a very slightly willbring body and surrounding saidv air chamber; a them in contact with the easing wall and diaphragm adapted to t said body and e'ectually seal against passing ofV mud serve as the bottom of a receptacle formed downward. Novel and valuable advantages by the walls of said body and said dialie with my type of plug, namely, friction phragm, the same being provided with a .Y

between plug and casing 1s reduced to a central aperture for the passing of said rod, minimum; sections 3"---3a of the cap 3 will and multiple perforations through which pass the burred ends of the casing withsaid iller may be poured; and an automatiout damage; copper is easily cut and later cally expandible cap comprising a metallic ground into ne powder by the drilling cup adapted to it into said receptacle, the tools, and because of its high specific gravsides thereof being divided by slits into mulity this powdered dbris will sink to the tiple sections adapted to are peripherally bottom of the hole; any amalgamation or when said cap is illed and pressure exerted binding of the metal with mud is impossithereon; said cap being provided with .a ble, so that in powdered form it will be car- `tubular guide corresponding to the center ried readily in suspension through the drill perforation in the bottom thereof adapted pipe and screen. to receive said rod and against the free end Having thus disclosed the construction of which said nut advances. Y and mode of operation of my well cement- In witness whereof I have signed this ing plug; I claim as new and desire to obapplication and power of attorney in the tain Letters Patent of the United States presence oi two subscribing witnesses. u on:

I)1. A metallic plug of the character dis- EDWARD F RAYMOND' closed comprising a cylindrical tubular Witnesses: v body; a hermetically se led air chamber P. G. JOYCE, positioned in approximately the center of 4D. L. CosBEY.

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