Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS2178845 A
Publication typeGrant
Publication dateNov 7, 1939
Filing dateOct 10, 1936
Priority dateOct 10, 1936
Publication numberUS 2178845 A, US 2178845A, US-A-2178845, US2178845 A, US2178845A
InventorsBaker Reuben C
Original AssigneeBaker Oil Tools Inc
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Safety circulation medium for well casings
US 2178845 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

Nov. 7, 1939. R. c. BAKER 2.178.845


AJLTORNEY Patented Nov. 7, 1939 UNITED STATES PATENT OFFICE SAFETY CIRCULATION MEDIUM FOR WELL CASINGS Reuben C. Baker, Coalinga, Oalifi, assignor to Baker Oil Tools, Inc.,

Huntington Park, Califi,

3 Claims.

This invention relates to the operation of casing deep oil wells.

There are instances during the lowering of the casing into an oil well bore, or during the cementing of the same in an oil well bore, that circulation downwardly through the casing is shut off. This may be caused by clogging of the casing or fittings on the casing along its length, or due to circumstances and conditions which prevent fluid from passing upwardly beyond a certain point along the casing between it and the wall of the bore. The many other reasons and circumstances which cause prevention of circu lation downwardly through the casing are well known to those skilled in the art and are too numerous to set forth here.

It is the principal object of my present invention to fit the well casing with means uninterfering with circulation downwardly through the casing in the usual manner under normal conditions, but which means is responsive to increased pressure in. the casing resulting from the shutting ofi of such normal circulation to provide a means of circulation above the point of shut-oil.

In practicing my invention, I fit the casing intermediate its ends with a medium which is responsive to increased pressure within the casing to permit circulation through the side wall of the casing. The pressure to which such medium is responsive is preferably definitely greater than the pressure required for normal circulation downwardly through the casing and upwardly between it and the walls of the hole.

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 diagrammatic view showing a casing positioned in a well bore and constructed in accordance with my present invention.

Fig. 2 is an enlarged view in section of the casing showing my improved circulating plug fitted thereto.

Fig. 3 is an enlarged view in external elevation of the device shown in Fig. 2.

Fig. 4 is an enlarged fragmentary view in vertical section through the three ports disclosed in Fig. 1, showing the different diameters of the shear pins connecting the, closure means to the casing.

Referring more particularly to the accompanying drawing, l0 indicates an oil well bore and II indicates the water string of blank casing therein. As previously pointed out the present invention is concerned with a safety medium for opening a circulation port in the casing intermediate its ends when circulation cannot 'be established through the lower .end of the casing. For this purpose the casing is formed with a radial aperture II a through its side wall which is internally 5 threaded to receive a bushing l2. The aperture I la may be formed in a fitting interposed between casing lengths or may be formed directly in the casing itself, if it is so desired, and when I use the term casing herein, I mean either the cas- 10 ing lengths pro-per or 'any fittings connected therewith.

The bushing I2 is bored coaxially as at l5 so as to form a circulation port communicating at its inner end with the interior of the casing and 15 at its outer end with the space exteriorly of the casing. Slidably fitting within the circulation port or bore I5 is a plug l6 which is hollow and cylindrical. The outer end of this plug I6 is closed as at IT and the inner end thereof is open 20 as illustrated. The inner end of the plug is surrounded by an exterior annular fiange iii of a diameter greater than the circulating port or bore IS. The length of the plug between the annular flange l8 and its closed outer end I! is greater 25 than the length of the port or bore I5.

The side wall of the plug I 6 is formed with a radial port I9 closely adjacent to its outer end, as most clearly illustrated in Fig. 2. A transversely arranged shear pin 20 normally secures 80 the plug IS in the bore or circulating port l5 with its outer end flush with the exterior of the casing. In this position the radial port l9 in the ping I 6 is covered by the wall of the bore I 5 so that it will be inefiective to permit circula- 35 tion through the plug and casing. The shearing strength of the pin 20 is so calculated that it will be sheared when the pressure on the plug from within the casing exceeds a predetermined value. I prefer that this pressure he definitely 40 greater than the pressure normally necessary to establish and maintain circulation through the casing in the usual and normal manner. The margin of difference between the pressure necessary to maintain normal circulation and that necessary to shear the pin 20 depends, of course, on the operators judgment and the depth of the well into which the casing is interposed.

When the pressure builds up in the casing to the predetermined point, the pin 20 will be sheared 50 and the plug IE will be moved radially outward with respect to the casing until the flange l8 engages the inner periphery of 'the casing, at which time the port ill will be uncovered and disposed beyond the exterior of the casing so that circulation can be established through the circulating port [5 from the'interior of the casing to the space surrounding the exterior thereof.

It is obvious that should the auxiliary circulating port l5 and its associate mechanism just described be fitted to the casing at a point above its lower end and circulation should, for any reason, be shut off below such auxiliary circulating port, that a'definite and predetermined rise of pressure inthe casing will be followed by shearing of the pin 20 and opening of the circulating port [5 so that circulation may be established at that point along the casing. v

It is obvious, of course, that when circulation is shut ofi at the lower end of the casing that the pressure in the casing will automaticaly rise until that pressure required to open the auxiliary circulating port I5 is reached.

In a long string of casing, as illustrated in Fig. 1, I may prefer to use more than one auxiliary circulating port l5 and I prefer that they be opened in response to progressively increasing pressures in the casing in an upward sequence. This is accomplished, of course, by merely progressively increasing the diameter of the shear pins 20a and 20b of the upper closures of the circulating ports as shown in Fig. 4. In this ar-- rangement circulation may be established at the lowest possible point above the point of shut-off so that. if circulation cannot be eflected through the lower end of the casing, the pressure will rise to the point sufilcient to open thefirst auxiliary circulating port, and if circulation cannot be broken. at that point, pressure in the casing will rise to open the next uppermost circulating port i511 and so on until circulation is established.

From the foregoing it is obvious that I have provided a very eflicient medium for enabling circulation to be broken through the side wall of a blank string of well casing above the point where circulation could not be established or maintained.

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. In combination with a string of blank well casing, said casing having a circulation port formed therein at an intermediate point therealong, a closure for said port, a shear pin normally maintaining said closure effective, said shear pin being capable of being sheared by a predetermined pressure in the casing to render said closure inefiective.

2. In combination with a string of blank well casing, said casing having a plurality of circulation ports formed therein at longitudinally spaced intermediate points therealong, a closure for each port, shear means for each closure normally maintaining the same effective, said shear means being sheared in an upward sequence in response mg the same, a shear pin connecting said plug.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2644530 *Sep 20, 1948Jul 7, 1953Baker Oil Tools IncGas-operated well apparatus with expansion retarding device
US2737195 *Dec 14, 1951Mar 6, 1956Baker Oil Tools IncSubsurface back pressure valve apparatus for effecting automatic fluid filling of well casing
US2751022 *Dec 14, 1951Jun 19, 1956Baker Oil Tools IncApparatus for allowing well conduits to fill with well bore fluid
US3239008 *Nov 5, 1962Mar 8, 1966Baker Oil Tools IncHydraulically set tandem packer apparatus
US3360047 *May 18, 1965Dec 26, 1967Burnett Bob JWell drilling device
US3381756 *Sep 3, 1965May 7, 1968Otis Eng CoWell tools
US4286662 *Nov 5, 1979Sep 1, 1981Page John S JrTubing drain
US4577702 *Mar 28, 1985Mar 25, 1986Faulkner Oil Field Services, Inc.Method of preventing drill string overflow
US5165478 *Sep 16, 1991Nov 24, 1992Conoco Inc.Downhole activated process and apparatus for providing cathodic protection for a pipe in a wellbore
US5224556 *Sep 16, 1991Jul 6, 1993Conoco Inc.Downhole activated process and apparatus for deep perforation of the formation in a wellbore
US5228518 *Sep 16, 1991Jul 20, 1993Conoco Inc.Downhole activated process and apparatus for centralizing pipe in a wellbore
US5346016 *Apr 20, 1993Sep 13, 1994Conoco Inc.Apparatus and method for centralizing pipe in a wellbore
US5379838 *Apr 20, 1993Jan 10, 1995Conoco Inc.Apparatus for centralizing pipe in a wellbore
US6095247 *Nov 21, 1997Aug 1, 2000Halliburton Energy Services, Inc.Apparatus and method for opening perforations in a well casing
US6457528Mar 29, 2001Oct 1, 2002Hunting Oilfield Services, Inc.Method for preventing critical annular pressure buildup
US6591915 *May 23, 2001Jul 15, 2003Fike CorporationMethod for selective draining of liquid from an oil well pipe string
US6675898Aug 13, 2002Jan 13, 2004Hunting Energy Services, LpApparatus for preventing critical annular pressure buildup
US6752212 *May 22, 2003Jun 22, 2004Fike CorporationDump valve assembly for selective draining of liquid from an oil well pipe stream
US7090027 *Nov 12, 2003Aug 15, 2006Dril—Quip, Inc.Casing hanger assembly with rupture disk in support housing and method
US7191830 *Feb 27, 2004Mar 20, 2007Halliburton Energy Services, Inc.Annular pressure relief collar
US8016035 *Oct 25, 2004Sep 13, 2011Baker Hughes IncorporatedChemical injection check valve incorporated into a tubing retrievable safety valve
US8967272Feb 20, 2014Mar 3, 2015Hunting Energy Services, Inc.Annular pressure relief system
US20040216867 *Jun 7, 2004Nov 4, 2004Burris Mark A.Dump hole dump valve
US20050098210 *Oct 25, 2004May 12, 2005Strattan Scott C.Chemical injection check valve incorporated into a tubing retrievable safety valve
US20050189107 *Feb 27, 2004Sep 1, 2005Mcvay Chester S.Annular pressure relief collar
USRE38616 *Sep 4, 2001Oct 12, 2004Halliburton Energy Services, Inc.Downhole equipment, tools and assembly procedures for the drilling, tie-in and completion of vertical cased oil wells connected to liner-equipped multiple drainholes
EP1882808A1 *Jun 19, 2007Jan 30, 2008Sam SimonianFlow restrictor coupling
EP2128376A2 *Jun 19, 2007Dec 2, 2009FloTech Holdings LimitedFlow restrictor coupling
WO2008155578A1 *Jun 18, 2008Dec 24, 2008Sam SimonianFlow restrictor coupling
U.S. Classification166/223, 251/145, 166/319, 166/317, 137/70
International ClassificationE21B33/134, E21B17/00, E21B33/13
Cooperative ClassificationE21B17/00, E21B33/134, E21B34/063
European ClassificationE21B17/00, E21B33/134, E21B34/06B