US2637401A - Drill stem packer with deflating means - Google Patents

Description

May 5, 1953 G. H. -RAMSEY DRILL STEM PACKER WITH DEFLATING MEANS Filed Nov. so, 195o i/x w 9 VVV/AEE;

Gec'rqge H. Qamseg' Sav amber* 7 Cltborrze Patented May 5, 1953 DRILL STEM PACKER ^DELAIING MEAN S George Ramsey, Tulsa, 0km., :assigner Lto .Standard .Oil "Development-Company, ya corporation of Delaware Agpplie'ation'November 30, 1950, 'Serial'rNoflSSSV (Cl. ,16B-,101)

A laims. l

Thisinvention concernsapparatus Tor iuse'ill oil Wells. The vapparatus of this invention vis `to be employed 'with a 'balloon-type packer of lthe nature used -in sealingolf'a particularportion of an oil well. Thelapparatus maybe defined 'as ,a deflating toolfto control the deilation oi a balloon packer when `and if desired. In accordancewith this invention a `drill-stem-type balloon packer is employed, equipped Awith an inflation valve positioned Within the drill stem at the upper termination of the "balloon packer The deflatingtool, comprising a valve tripping rnechanisrfi ladapted to .be dropped throughithe drill stem `to operate the said inflation valve causing deiiation, is .ernployed with this packer.

Atthe present time, "balloon-type `packers are -frequently usedin testing for and -in producing oil from `a bore hole. Balloon-type vpaclners ,are primarily used Afor two purposes. First, ysuch packers lmay be employed to Yseal 01T particular portions of =a bore hole. Thus, for example, it may be desirable to seal a waterproducing portion 'of abore hole from an oil-produeingportion of ka bore hole. By positioning `and inilating .a suitable balloon'packerin the 4bore hole, this ,objective may often be accomplished. LSecondly, balloon packers `may .be .employed in ,a wide varietyso'f formation testing equipment. Thus .a number of types of formation testers are Anow known to the artemployingan inflatable :balloon packer to .seal va lparticular .portion of vthe .bore hole ina manner to vpermit sampling-of fluidsyproduced in the bore hole at or adjacent thepoint sealed'lby the balloon packer.. For example, porous pasagew'ays may be Vprovided ,in the walls of the Lballoon packer through which `uids may be drawn ,from theportion of the bore holegsealed by the packer.

AIn employing v-a .balloon vpacker -lfor these @or other purposes, problems have :arisen `as tothe best manneryof controlling ,the :inflation and'subsequent `deflation of the packer. vWhile :many methods have .been devised .and suggested, A:the present `invention 'concerns a :novel apparatus adapted to betr control 'deation of :bail-oon packers `as desired.

In accordance with 4this A:invention a drill zstem balloon lpacker is employed `which is `provided withfa checkvalvegposi-tioned at'the juncture oli thepacker apparatus with the drill stein. 'This chec'kvalve'is placed-in a fluid cond-uit extending between the finside of the `drill stem L `the insideof'the balloon packer. .Ijhe checlevalveis positioned `and employed to permit `flow of fluid through the drill l' stem 'into the 'balloon ``packer to vabout the 'backing rings.

cause inflation 1of theballoon packer. However, positioning the check valve :in 'this manner aprevents the reverse :flow of 'luid, fso that the check valve is normally 'operative to 'prevent deation of ithe lpacker once the ypacker has been inated. In order to control Athe deilation of VVa balloon packer of this character, in accordance .with-this invention, a -valve tripping apparatusis employed to trip the check valve heretofore described. Thus, when it is desired to A'deflate 'the balloon packer, this apparatus -is lowered y'or ydropped downfthe drill stem to `contact the f'check valve controlling iniiux and eiux of `liquid from fthe balloonpacker It is 'a particular feature of l'this valve tripping `apparatus that an additional 4check valve `within the tripping 'stool is "used Lto prevent ination 7of the balloon packer oncefit has been deliated. A

The general-=objectives and advantages of 'this apparatus ymay bezunderstood Vfrom-the -following Adetailed description of one operative `ernbodiment of this invention. The appended drawing dia- `grannnatically illustratesin cross'sect'ional elevational detail the type of balloon packer with lwhich this invention is concerned yand ja specific valve tripping :apparatus vprepared in :accordance with this invention. v"In the drawing, the packer Vis shownin vits inatedposition, with the deiatin'g ,toolin operativeposition to cause denationof the packer.

Referring to the dra\vin g,1a borehole .l5 is diagrammatically illustrated. :Assuming :that it :is desired tofemploy a'balloon packer iat some jportion o'f the `boreglrijoleJ the ,deflated packer assembly is attached toa drillstern TLB vand isilowere'd down .the .bore hole. The Ypacker assembly gin- .cludes the -.elastic Apacker il .which is sp refs'arably fabricatedof rubber laminated with xa strong fabric. ,Alternatively the packer may be oomposed solely fof Yrubber or fabric vor tany other desired ,material 'capable :of icontaining a luid seas to` permit. expansion orinnationfoi thefpackkerwhen-Huid is pumped into'thefpacker. Arnetal supportingsrod or mandreli passes through Vthe packer and/is :rred to or is'lan `integral -pa-rt of a'backingming ',ZSfat the uppertermination ofthe packer. A `.similar .backing lring l(not shown) .iis positioned onrnandrel 23 `iat `the .lower termina* tion of the l packer. 'The :packer :may thus ,be4 xed to .the lupper and lower backing rings 'by means of `adhesives lor by wire lwrapping the `packer Cylindrical metal-lic connectors `l and -30 4may be maintained v*threadedrelation 'to each other and-to thedrlll string vvkl'l fand the backing ring 29,4150 riixzethe packer assembly to the drill string. When the balloon packer is lowered to the desired point in the bore hole, inflation of the packer is achieved by pumping drilling mud or other fluid down the drill stem. During the lowering and lnflating of the packer, the deflating apparatus, generally indicated by numeral 2, is of course not employed, and is not in the position shown in the drawing. Drilling mud flowing downwardly through the drill stem may flow into the packer II through the check valve assembly 9. Thus drilling mud will be forced through the drill stem and through the orifices I8 of check valve 9 for entrance to the inside of packer Il through conduit I8 and ports 2l, positioned in mandrel 28. By pumping drilling fluid down the drill stem in this manner, the packer may be suitably inflated.

The valve stem of check valve 9 extends through the top of the check valve and terminates as an enlarged globe 3I. Spring 32 positioned around the valve stem acts against the globe 3I and the top of the check valve to normally maintain the valve closed. However the strength of spring 32 is selected to permit opening of the valve when fluid is forced through ports I3 of the valve as described.

For the purposes of this invention, the check valve assembly is positioned at the upper termination of the elastic packer assembly and preferably is centrally positioned.

After inflation and use of the balloon packer, it then becomes necessary to deflate the balloon packer so that it may be removed from the bore hole or moved to a different portion of the bore hole. In accordance with this invention, the valve tripping mechanism depicted in the drawing is lowered or dropped down the drill string. The valve trip-ping mechanism, generally indicated by numeral 2, has suflicient weight to open the check valve 9 when the tripping mechanism bears on the stem of the check valve. By this means the check valve 9 is opened so as to permit the flow of fluid from within the balloon packer through the check valve and up the drill stem, securing the deation of the balloon packer.

In order to positively direct the tripping mechanism so as to contact the valve stem, a portion of the cylindrical connector 1, directly above the check valve, is preferably formed so as to have an inner bore of substantially reduced cross sectional area. This presents a restricted opening surmounted by sides 20 sloping upwardly and outwardly, as illustrated, into which the tripping mechanism will be guided so as to contact the valve stem to trip the check valve.

It is a particular feature of the invention that the tripping mechanism seats on the shoulders 20 positioned above the check valve 9. The tripping mechanism has sufficient weight and is shaped with a projection of reduced area providing shoulders so as to match shoulders forming a fluid seal when the tripping mechanism is in the position illustrated in the drawing. To permit a passageway for the escape of fluid from the inside of the balloon packer, ports 2I connect to an internal channel 22 within the tripping mechanism. Channel 22 terminates within the tripping mechanism in the form of an enlarged cavity or opening 23 from which ports 24 provide a fluid passage to the inside of the drill stem I6. A check valve is positioned in channel 22 to permit the flow of fluid upwardly through channel 22 from the balloon packer and to prevent the flow of fluid downwardly through channel 22 towards the packer. Such a check valve may readily be provided by positioning a steel ball or its equivalent, identified by numeral 4, at the entrance of channel 22 to the enlarged cavity 23.

By this arrangement when tripping mechanism 2 has been dropped downwardly through the drill stem so as to open check valve 9, and so as to seat on the shoulders 20, fluid may flow from the inside of the packer through conduit I9, check valve 9, ports 2I and channel 22 to the inside of the drill stem I6. This flow may be induced by pumping fluid from the inside of the drill stem. This is effective to cause the deflation of the balloon packer.

The balloon packer may then be removed from the bore hole by drawing the drill stem upwardly to the surface of the earth. It is a particular leature of the tripping apparatus disclosed that when this is carried out, reinflation of the balloon packer is impossible. Thus, even though a positive pressure differential is developed within the drill stem with respect to the pressure outside the drill stem, this pressure differential cannot result in the reinflation of the packer by virtue of the check valve positioned in the tripping mechanism; the check valve comprising the steel ball 4 at the upper termination of channel 22 in the tripping mechanism prevents flow of fluid to the balloon packer. On the other hand, should residual fluid within the [ballon packer I'I tend to reinflate the balloon packer as the packer is raised to points of lower pressure in the bore hole, this fluid may escape through channel 22 and check valve 4 to prevent the reinilation of the balloon packer. It is therefore to be seen that the valve tripping apparatus described is well adapted to control and to maintain the desired deflation of a balloon packer during withdrawal of the packer from a bore hole.

It is preferred to position a Spearhead I at the upper portion of the tripping mechanism 2, so that if desired, the tripping mechanism may be retrieved from the drill stern. Thus, for example, it may be desired to deflate the packer to move the packer to a different portion of the bore hole without necessity for completely removing the packer from the bore hole. In this case the tripping mechanism may be dropped into the drill stem to deflate the packer while the packer is moved to a different horizon in the bore hole. Thereafter a retrieving tool may be dropped through the drill stem so as to permit removal of the tripping mechanism and consequently to permit reinflation of the balloon packer as desired.

The invention has heretofore been described in a simplified manner in order to disclose the nature and operation of the invention. Thus, as described, a closed fluid passageway is provided throughout the length of the drill string, having access to the inside of the balloon packer through the check valve provided. In such a simple arrangement, inilation may be achieved by filling the drill string with fluid such as drilling mud and if necessary by applying a positive pumping pressure to the fluid within the drill string. This will serve to develop a pressure differential between the fluid within the drill string and the fluid within the bore hole around the drill string causing the balloon packer to inflate. In such a simple system, deflation is then achieved, as described, by balancing the hydrostatic pressure within the drill string and the pressure outside the drill string, when the deflating tool has been dropped into the drill string. Deilation may often be achieved simply by discontinuing pumping of fluid into the drill stem as the elasticity of the packer will cause deflation if the pressures are 5 balanced in this manner. Alternatively, or preferably, it may be desirable to pump fluid from the drill stem to create a negative pressure within the drill stem causing positive deflation of the packer.

While this system is operative, in the manner indicated, such a simple system is undesirable for a number of reasons. The principal reason is that inflation of the elastic packer is diflicult to control while avoiding use of infiating pressures which would cause the rupture or failure of the elastic packer. To overcome this difhculty, various expedients may be employed. One method which may be employed is to extend a fluid passageway 6 from the inside ofthe drill string to the outside of the drill string at some point above the check valve 9. An additional check valve 8 is positioned in this passageway and is spring-loaded to maintain the valve closed, except when a desired predetermined pressure differential exists between the inside and outside of the drill string. Check valve 8 will thus open when sufficient fluid has been pumped down the drill stem to create the indicated pressure differential which, by selection, is a pressure differential sunicient to inilate the elastic packer without causing rupture. The passage 6 may thus be considered as a by-pass or a pressure relief channel serving to limit the pressure differential within and without the elastic packer so as to prevent rupture of the packer.

It is apparent that the apparatus described is subject to many desirable modifications not heretofore specifically emphasized. Consequently, the following claims are properly to be construed to cover the various and divergent types of apparatus in which a balloon packer may be employed.

What is claimed is:

1. In a drill stem balloon packer apparatus comprising a supporting member attachable to a drill stem and having attached thereto a balloon packer, a passageway within said member to conduct iiuid from Within said drill stern to the balloon packer to cause inilation of the packer and a check valve in said passageway to hold i'iuid within said packer; a tool for deating said packer comprising a body adapted to pass down through said drill stem, a projection on said body adapted to open said check valve, a portion of said body closing off said passageway between the drill stem and the check valve, a channel through said body communicating between said drill stem and said passageway below said closed off portion and a check valve in said channel operating to block fluid ilow from said drill stem to said packer while permitting flow in the reverse direction.

2. A drill stem balloon packer apparatus comprising a supporting member attachable to a drill pipe, a balloon packer mounted on said supporting member, a passageway in said supporting member communicating from the drill pipe to the interior of said packer, a first check valve in said passageway normally passing fluid from said drill pipe to the interior of said packer while blocking iiuid flow in the opposite direction, said check valve having a movable member accessible to said drill pipe, said member on being moved operating to open said check valve to permit fluid flow out of said packer into said drill pipe, an elongated body adapted to pass down through said drill pipe to engage and move said movable member, a portion of said Abody being shaped to close off said passageway between said drill pipe and said first check valve, a channel in said body communicating between the interior of said drill stem and said rst check valve and a second check valve in said channel operating to block iiuid flow from within said drill stem to said first check valve while permitting fluid now in the reverse direction.

3. A drill stem balloon packer apparatus comprising a supporting member attachable to a drill pipe, said supporting member having an interior chamber and a passageway connecting said chamber with the interior of said drill pipe, a portion of said passageway being of reduced diameter presenting an upwardly facing shoulder, an inflatable balloon packer xed to said supporting member, a conduit communicating between said chamber and the interior of said balloon packer, a check valve in said conduit normally permitting fluid iiow from said chamber to the interior of said packer and blocking uid flow in the reverse direction, a movable projection on said check Valve extending into said chamber, said projection on being moved operating to permit iluid now out of said packer into said chamber, an elongated body adapted to pass down through said drill pipe into said passageway, the lower portion of said body being of reduced diameter and of suicient length to project through said reduced diameter portion of said passageway into said ,chamber to engage and move said check valve projection, the contour of said body adjacent said lower reduced diameter portion presenting a surface seating on said up- Wardly facing shoulder whereby to seal the drill pipe from said chamber, a channel in said elongated body having a port opening into said drill pipe and a port opening into said chamber, and a second check valve in said channel operating to block fluid flow from within said drill stem to said chamber While permitting fluid flow in the reverse direction.

4. The apparatus defined by claim 3 in which the said elongated body is surmounted by a projection adapted to engage a retrieving tool.

GEORGE H. RAMSEY.

References Cited n the file of this patent UNITED STATES PATENTS Number Name Date 2,231,282 Norris Feb. 11, 1941 2,418,500 Chambers Apr. 8, 1947 2,497,185 Reistle, Jr. Feb. 14, 1950 2,521,332 Blood et a1. Sept. 5, 1950

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