US1712948A - Apparatus for cementing oil wells - Google Patents

Description

Patented May 14, 1929.

DONALD D. BURCH, OF OKMULG-EE, OKLAHOMA.

APPARATUS FOR CEMENIING OIL WELLS.

Application filed June 21,

This invention relates to apparatus for cementing oil wells and more particularly to an improvement of the oil well cementing apparatus disclosed in my prior patent, No.

1,603,447, granted October 19, 1926, for casing shoes.

An important object of the invention is to so rearrange the structure disclosed in this prior patent that the plug is much more readily drilled out after the cementing operation has been completed and is much more readily installed for service.

A further object of the invention is to produce a device of this character so constructed that the elements thereof may be formed and separately shaped and the assembly thereof completed by the purchaser, thus materially reducing the cost of shipment and the difiicuh ties of transportation. In this connection, it is pointed out that oil wells are often located at almost inaccessible points and the transportation of heavy materials is always a serious problem.

These and other objects I attain by the construction shown in the accompanying drawings, wherein for the purpose of illustration .is shown a preferred embodiment of my invention and wherein 2- I igure 1 is a vertical sectional view through apparatus for cementing wells constructed in accordance with my invention, a plug being disclosed as seated upon the upper end of the control element to close the upper ends of the conduits thereof;

Figure 2 is a horizontal sectional view therethrough.

In accordance with the present invention, I provide acasing shoe 10, the interior wall of which is circumierentially recessed, as at 11, to provide shoulders or seats preventing movement of acast concrete plug 12, which may be formed therein. In combination wlth this casing shoe, I provide a control element, whichcomprises a central casing 13 having in communication with the upper end there-. of a conduit orconduits 14, the ends of which are downwardly directed and extend belowthe lower level of the casing. Communicating with the bottom of the casing are conduits 15, the ends of-which are upwardlyduected and extend above the top of the cas.1ng.'- Interiorly, the casing is provided w th avalve seat 16 having cooperating therewith a check ball or check valve of any suitable character, designated at 17 and seating downwardl In the use of the apparatus, as descri ed,

1927'. Serial No. 200,424.

the control element is placed in the casing shoe in alignment with the recess 11 and ce- {nent poured thereabout to form theplug 12 in whlch the control element is completely embedded, with the exception of the fact that the ends of the conduits l4 and 15 open tively.

In cementing a well, this device is attached to the lower end of the casing and when the casing is at the proper position, pump pressure is applied to drive the cement through the control element where, in its passage, it lifts thecheck ball 17, passes the same and discharges from the lower end of the casing shoe through theconduits 14. After the cement has been completely forced through the control element which, may be determined by the fact that aplug 18 following the same seats upon the upper end of the control ele ment and closes the upper ends of the con-i duits 15, the pump pressure is relieved and any tendency of the cement to return to the interior of the casing through the control element will be prevented, by reason of the fact that thecheck 17 will seat and will be held seated by the pressure of the incoming cement.

When the cement has fully set, theplug 18 which, if desired, may be of cement and theplug 12 are drilled from the shoe in the usual manner. The control element may be formed I from tin or galvanzed iron of light gauge and will not materially interfere with the drilling operation, as is the case with a heavy metallic body, suchwas described in my prior patent above mentioned. While I have above referred to theplug 12 as being constructed of concrete, it will readily be ,pnderstood that this plug may be constructed of any castable material which is readily drilled from the shoe without dama e to the drill. Among such substances mig t be mentioned in addition to the concrete previously mentioned wood or paper pulp and plaster of Paris. All of such substances, however, should be ma terial which can be readily pulverized.

Since the construction hereinbefore set forth is capable of a certain range of change and modification without mater ally departing from the spirit of the invention, I do not .limit myself to such specificstrueture except as hereinafter claim I claim:- 1. In comblnatio'n, a. casmg shoe having 1ts interior wall recessed, a cast concrete plug through the bottom and top thereof respec- I within the shoe and having: portions extending into said recess whereby the plu is held against movement with relation to t e shoe; a control element cast within the plug having means permitting fluids to flow through the plug from the upper to the lower end thereof, but preventing return flow of suchflu1ds,' the control element comprising acas ing, a conduit communicating with the upper end of the casing and extendin downwardly through the bottom of the p ug, 'a second conduit communicating with the bottom of the casin and extending upwardly through end thereof, a plurality of conduits arranged eccentrically to the chamber and extendm between said valve seat and the up or on of the plug formingvcommunications etween the interior of said chamber and the interior of thecasing shoe above the plug, other conduits arranged eccentrically to the chamber intermediate the other conduits and extending between the lower end of the plug and the upper end of the chamber forming communication therebetween, a ball valve in the chamber ada ted to cooperate with the valve seat; said bal valve permitting fluids to flow from the up er end of the plug throu h the chamber an through the lower end t ereof but being seated by the return flow of fluid from the bottom of the plug to prevent the fluid from 'pass' through the plug. In testimony v vffie signature.

' DONALD D. BURCH,

reof I hereunto afiix my 40

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