US3850250A - Wellbore circulating valve - Google Patents

Abstract

A wellbore circulating valve especially useful in a string of testing tools ultilizes a sequentially ratcheted inner mandrel which covers a series of flow ports and is opened by a predetermined sequence of operations which move the mandrel away from the flow ports thereby communicating the annulus with the inner bore of the tool.

Description

United States Patent 1191 Holden et al.

[ Nov. 26, 1974 [54] WELLBORE CIRULATING VALVE 3,306,366 2/1967 Muse 166/128 x 3,361,212 1/1968 Page, Jr. 166/224 R [751 lnlemorso 0mm, Gary wray 3,433,301 3/1969 McEver, Jr. 166/128 both of Duncan, Okla' 3,456,723 7 1969 Current et al. 166 134 x 3,507,327 4/1970 Chenoweth.......... 166/134 [73] Asslgnee' gi Company Duncan 3,570,595 3 1971 'Berryman 166 226 3,664,415 5/1972 Wray et al. [66/5 [22] Filed: Sept, 11, 1972 3,750,749 8/1973 Giroux 166/224 R [21] Appl 1 Primary Examiner-James R. Boler Attorney, Agent, or Firm-John H. Tregoning; Floyd [52] US. Cl 166/315, 166/226, 166/95 A. Gonzalez; James E. Cockfield [51] Int. Cl E21b 33/00 [58] Field of Search 166/315, 224, 225, 226, 57 ABSTRACT 166/126,128,150, 152, 72, 73, 77.5, 95, 98, A 11b l l n f l 134, 181, 237, .5; 285/302, 303; 403/227, .clrcuamg especla a strmg of testmg tools u1t111zes a sequentially ratcheted 228, 345, 377, 294/8615, 86.21

mner mandrel wh1ch covers a senes of flow ports and d by a predetermined sequence of operations [56] References Clted 9 wh1ch move the mandrel away from the flow ports UNITED STATES PATENTS thereby communicating the annulus with the inner [S4123 bore of the tool, in seu 1 3,237,695 3/1966 Bostock et a1, 166/134 x 11 Clalms, 8Draw1ng Figures as 34 1 w 1Z PATEm gxavzslsm saw 3BF 3 FIG. 2'

FIG. 3

FIG. 1f-

FIGVI WELLBORE CIRCULATING VALVE BACKGROUND OF THE INVENTION After an oil well has been encased and cemented it usually becomes desirable to test the formations penetrated by the wellbore for possible production rates and general productivity of the well. In doing so, a test string containing several different types of tools is utilized to indicate the productivity of the well. These tools may include a pressure recorder, a sample chamber, a closed-in pressure tester, hydraulic jar, one or more packers, and several other tools. In addition, it is preferable to include one or more circulating valves in the string.

The testing procedure requires the opening of a section of the wellbore to atmospheric or reduced pressure. This is accomplished by lowering the test string into the hole on drill pipe with the tester valves and sample chambers closed to prevent entry of well fluid into the drill pipe. With the string in place in the formation, packers are expanded to seal against the wellbore or casing and isolate the formation to be tested. Above the formation the hydrostatic pressure of the well fluid is supported by the upper packer. The well fluid in the isolated formation area is allowed to flow into the drill string by opening the tester valve. Fluid is allowed to continue flowing from the formation to measure the ability of the formation to produce. The formation may then be closed in to measure the rate of pressure buildup.

After the flow measurements and pressure buildup curves have been obtained, one or more samples can be caught and then the test string will be removed from the well.

At this point the importance of the circulating valve becomes important. Since it is not desirable to pull the testing string while it may still be full of formation fluids and/or high pressure gas due to the danger of explosion and fire at the surface, plus the resulting contamination of the rig and rig floor with the crude oil and other formation fluids which leads to dangerous and slippery footing, it is almost mandatory that the formation fluids be reversed out under controlled conditions and bledoff away from the rig floor.

To accomplish this reversing out, the inner bore of the test string and drill pipe must be opened near the test tools so that displacement fluid (usually drilling mud) from the annulus can flow into the string to force out the formation fluids at the top where they can be piped away from the rig. The hydrostatic pressure from the displacement fluid is usually considerably higher than the formation pressure due to the high density of the mud and the height of the mud column in the well, therefore displacement from the annulus into the string and up to the surface usually occurs without the need for pumping. All that is required is that the annulus be placed in fluid communication with the bore of the test string at the proper time. During testing and sampling operations the hydrostatic fluids in the annulus must be isolated from the formation fluids to prevent contamination of the tests and samples.

Thus, it is only after the testing and sampling is completed that it is desirable to reverse out the remaining formation fluids in the tubing.

Several methods of accomplishing this are currently in use. One of these methods involves covering the ports through the tubing wall with an inner sleeve which is shear pinned to the tubing wall. When the sleeve is to be opened a weighted bar is dropped through the tubing to strike the sleeve and shear the pins, moving the sleeve downward to uncover the ports and communicate the annulus with the tubing bore. The disadvantages of this device are obvious; a deviated hole may cause the bar to bind in the tubing thereby blocking the tubing and preventing opening of the circulating valve sleeve and removing any chance of reversing out. Also slant holes may reduce the speed of the bar moving down the tubing because of friction between the bar and the tubing wall. A reduction in speed could lower the striking force of the bar to the point where the shear pins will not break and reversing out will not be possible. Also when some of the extremely heavy formation fluids are being recovered the bar may not be heavy enough in these fluids to shear the pins in the circulating valve, or there may be enough trash collected in the valve sleeve to cushion I the impact of the bar and prevent shearing of the pins.

Other types of circulating valves utilize reciprocal or rotational movement to operate the valve sleeve. The rotationally operated circulating valve suffers from the disadvantage that often the string may bind in the well bore so that the string has enough flexibility to allow rotation by twisting above the circulating valve. The operator at the surface may have no way of knowing that the rotation is not accomplishing the desired effect, or if he knows he may have no way of correcting it. The same defect occurs in the reciprocating tools, they may become lodged in a deviated well and the circulating valve becomes inoperable.

In addition, the above described circulating valves are unsatisfactory in offshore wells because the blowout preventers must be opened in order to manipulate the drill string or drop the opening bar into the pipe in order to open the circulating valve. This becomes extremely dangerous because well blowout, explosion, and fire become a possibility when the blowout preventers are released and this remains a constant threat until the preventers are closed.

The apparatus of this invention overcomes these difficulties by opening in response to controlled fluctuations in annulus pressure, requiring no manipulation nor activating members inserted onto the tubing.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I, which is broken into FIGS. 1a through If for convenience in drawing, illustrates a partial crosssectional view of the apparatus of this invention.

FIG. 2 is an elevational view of the latch mandrel showing the orientation of the latch blocks.

FIG. 3 is a blown-up cross sectional view of the threads on the latch mandrel and pull mandrel.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 depicts the preferred embodiment of the circulating valve apparatus 1 in which atubular latch mandrel 2 is concentrically and slidably located inside a segmentedtubular housing 3. Mandrel 2 has an externalbeveled shoulder 20 for engaging an internalbeveled shoulder 30 inhousing 3. This limits downward movement ofmandrel 2 inhousing 3.Housing 3 has one ormore ports 31 through the wall thereof which communicate from theinner bore 32 ofhousing 3 to theannular area 33 between the tool 1 and the well cas- In its lowermost position,skirt 21 oflatch mandrel 2 coversports 31 and prevents fluid communication therethrough.Circular seals 34 located ininternal grooves 35 ofhousing 3 provide fluid-tight seals betweenhousing 3 andmandrel skirt 21 above and belowports 31.

Valve sleeve 4 is a tubular sleeve having anupper skirt 40 and a lowerflanged end 41, with theskirt 40 being slidably located coaxially inside thelatch mandrel skirt 21 and having acircular seal 42 located inannular groove 43 for providing a fluid-tight seal betweenskirt 21 andskirt 40. Flangedend 41 extends out ofmandrel skirt 21 and is enlarged greater than the OD ofskirt 21 to preventskirt 21 from sliding over the flanged end. Abutment ofskirt 21 on flangedend 41 limits downward movement ofmandrel 2. Flangedend 41 is further extended into an inner annularrecessed groove 36 inhousing 3 which prevents upward or downward movement of valve sleeve 4 inhousing 3. Acircular seal 44 is located annularly aroundflange 41 to provide fluid-tight sealing contact withhousing 3.

Latchmandrel 2 has one ormore windows 22 through the wall thereof near theupper end 23 of the mandrel. Located inwindows 22 arecurved latch blocks 24 having curved internal threadedsurfaces 25 located on their inward faces.Retainer pins 26 are fixedly attached to the edges oflatch blocks 24 and arranged to abutrecessed shoulders 27 ofwindows 22 to limit inward movement ofblocks 24 inwindows 22.

Latch blocks 24 are arranged to move outwardly fromwindows 22 in response to wedging forces pushing them outward.Spring elements 28 encircle blocks 24 ingrooves 29 andlatch mandrel 2 and provide a spring force tending to pressblocks 24 inwardly inwindows 22 thereby providing a constant but yieldable restraining force thereon.

Pull mandrel is a tubular cylindrical sleeve located concentrically within thelatch mandrel 2, having ahelical thread 50 which engages and matches thehelical thread 25 insidelatch blocks 24. Alternatively, instead of threads at 25 and 50, circular parallel grooves could be used in the latch blocks and on mandrel 5. Referring now to FIG. 3,threads 50 have asloped face 62 on their lower leading edge and a slightlysloped face 63 on their upper trailing edge.Threads 25 have a slightly slopedface 64 on their lower edge and asloped face 65 on their upper edge. This allows downward longitudinal movement of pull mandrel 5 throughlatch mandrel 2 by means of wedging action of the sloping face ofthreads 50 on the sloping face ofthreads 25, which wedging action forces latchblocks 24 outward and allows telescopic movement of mandrel 5 intomandrel 2. The wedging forces required to move latch blocks 24 outward and allow mandrel 5 to telescope intomandrel 2 must necessarily be less than those holdingmandrel skirt 21 in position inhousing 3, which are the friction forces of seal rings 34 and 42.

Upward movement of pull mandrel 5 results in abutment of the backwardly sloped faces 63 and 64 ofthreads 50 and 25 which results in likewise upper movement oflatch mandrel 2. A subsequent downward movement of pull mandrel 5 intolatch mandrel 2 achieves another wedging outward of latch blocks 24 and allows the pull mandrel to take another bite on the latch mandrel, and through this ratcheting type of action, will allow a sequential train of upward and downward movements of the pull mandrel to result in a complete extension of the latch mandrel and skirt out of the annular area between the valve sleeve 4 andhousing 3.

Faces 63 and 64 ofthreads 50 and 25 respectively are illustrated having a slight back slope of around 2 to 10, with a preferable angle of about 5. This provides a positive locking engagement ofthreads 50 and 25 when they are moving in such a relationship, one to the other, that faces 64 are abutted with faces 63. It is contemplated that the back angle offaces 63 and 64 with the vertical in FIG. 3 may be anywhere from 0 to 60 and the forward angle offaces 62 and 65 may be from about 10 to about with the vertical.

A preferred angle forfaces 62 and 65 for optimum strength and good wedging action appears to be around 45.

Upward travel of the latch mandrel about the pull mandrel will be limited by abutment of theupper mandrel end 23 with exteriorannular shoulder 51 attached to the pull mandrel.Shoulder 51 may be an integrally formed shoulder or can be a threaded collar fixedly attached to the upper end of mandrel 5.

Threadedly attached to the upper end ofhousing 3 isadapter 6 which has an internally projectingshoulder 61. This shoulder may be formed by machiningadapter 6 with a smaller ID than that of the housing at the point where they are threadedly attached.Spacer 7 is slidably located withinhousing 3 and around the upper extension mandrel 8 so that upward travel of the pull mandrel is limited by abutment ofshoulder 51,spacer 7, andshoulder 61.

Referring to FIGS. 1a to If which are continuations of FIG. 1 and show the apparatus broken in order to more easily locate the drawings on the page in as large a detail as possible,adapter 6 is shown threadedly engaged in theintermediate housing 9 which, in conjunction withupper housing 10, contains the power section 11 for actuating the valve section 1.

Extension mandrel 8 extends upwardly throughadapter 6 andintermediate housing 9 and is threadedly engaged in thecylindrical orifice mandrel 12. Acylindrical piston mandrel 13 is fixedly attached to the upper end oforifice mandrel 12 via lower section 14 and has an extendedupper skirt section 15.

Adapter collar 16, having a narrowed ID, is threadedly secured toupper housing 10 and has an exteriortubular extension 17 threadedly attached to its upper end, and concentricinner extension 18 fixedly attached interiorly thereto.

Thus, it can be seen in FIGS. 1d and 1e that the power section generally consists of a stationary outer casing and a slidable inner member, with the outer casing consisting substantially ofadapter 6,intermediate housing 9,upper housing 10,adapter collar 16,tubular extension 17, andinner extension 18. The slidable inner member consists of extension mandrel 8,orifice mandrel 12,piston mandrel 13, lower section 14, andupper skirt 15.

A differential piston arrangement is provided bydifferential piston area 19 on the upper end ofpiston mandrel 13. This area works in conjunction withpiston chamber 37 to provide a power actuating source for the power section 11.Piston chamber 37 is formed by the relatively large inner diameter ofhousing 10 and the narrow inner diameters ofadapter collar 16 andhousing 10. A gas-tight seal is provided bycircular seals 38 located in exterior annular grooves 39 onpiston mandrel 13. Power fluid access to thedifferential piston area 19 is achieved through one ormore ports 45 through the wall ofupper housing 10, communicating withannular space 46 between the enlarged upper section ofpiston mandrel 13 andhousing 10.Piston chamber 37 is shown in broken construction to reduce the length of the drawing. In actuality, it is considerably longer than pictured and can be made of any variable length which results in sufficient volume to provide the desired spring effect. In one embodiment, this chamber comprises approximately one-half of the length of the power section and contains an inert gas under pressure to provide a return force onface 47 ofpiston mandrel 13 so that after the pressure is removed from the actuating fluid inarea 46 the compressed gas inchamber 37forces piston mandrel 13 back down to its initial lower position.

A mechanical spring can be used in place of or in conjunction with the inert gas inchamber 37 to vary the restoring force on piston 14. This variance can also be obtained by either varying the initial pressure of inert gas inchamber 37 or by varying the volume ofchamber 37, or by both means.

Actuating force can be varied by increasing or decreasing thedifferential area 19 ofpiston 13 by reducing the OD ofpiston 13 belowface 19, or by increasing the ID of housing and the OD ofpiston face 19, or by both methods.

Sharp upward movement of the inner member within the outer members is prevented by the reaction of the orifice mandrel in thedampener chamber 48. Theorifice mandrel 12 has anintegral orifice collar 49 which moves slidably inannular chamber 48 formed betweenhousing 9 and the narrowedsection 52 ofmandrel 12.Chamber 48 is filled with some durable non-corrosive fluid such as hydraulic oil and is a fluid-tight sealed chamber. Asmandrel 12 moves upward inhousing 9,collar 49 must traverse sealedchamber 48 which is filled with fluid. To do so, the fluid above the collar must traverse throughorifice channel 53 to below the collar. Circular seals 54 located in grooves 55 incollar 49 seal against the inside ofhousing 9 and prevent leakage of fluid aroundcollar 49. The effect of movingcollar 49 throughchamber 48 and allowing fluid to flow only through the restricted orifice channel is that movement of the inner mandrels in the outer housing is dampened to prevent sudden large movements therein. As the movement actuating force increases, the dampening force of the orifice arrangement increases correspondingly.

When the actuating force onpiston face 19 is removed, it is desirable that themandrels 12 and 13 be allowed to move downward relatively unrestricted so a bypass check valve arrangement is provided at 56 to allow fluid to flow from the lower side ofcollar 49 throughchannel 57 to the upper side inchamber 48 relatively unhindered, thereby bypassingorifice channel 53. This is provided since the spring constant of the gas spring inchamber 37 is preset at a non-excessive level to prevent damage to the apparatus through sudden sharp return of the piston mandrel to its initial position.Channels 53 and 57 are in continuous fluidic communication with the lower side ofcollar 49 throughchamber 58 which is an annular chamber passing completely around the exterior circumference of the extension mandrel 8. Likewise,chamber 48 is an annular chamber completely surrounding mandrel 8. There may be one ormore orifice channels 53, and one ormore bypass channels 57.

In operation the entire apparatus is connected into a testing string, for instance, by threading the upper ends ofextensions 17 and 18, and the threadedlower end 59 of the valve section 1 into the test string.

The string can then be lowered into the hole and the formation tested. The use of this apparatus is particularly advantageous in conjunction with the annulus pressure operated sampler disclosed in US. Pat. No. 3,664,415. The advantages of pressure operated tools are particularly felt when operating in an offshore well where it is highly preferable to maintain the blowout preventer rams closed at all times which naturally prevents any type of manipulation of the test string to operate the various tools in the well. The types of manipulations commonly used are rotation and reciprocation or combinations of the two, all of which cannot be performed with the blowout preventers in place.

Therefore, the tool of this invention is extremely safe and advantageous for use in offshore wells and unpredictable high pressure inland wells. When the tool string is in place in the well and the blowout preventers are closed in on the testing tools the sampler can be activated by applying hydraulic pressure to the annulus between the tool string and the casing.

The increase in annulus pressure reacts throughports 45 and againstdifferential area 19, forcingpiston mandrel 13 upward against the spring means inchamber 37. As the piston mandrel moves upward it simultaneously pullsorifice mandrel 12, extension mandrel 8, pull mandrel 5, latchmandrel 2 andskirt 21 upward untilshoulder 51contacts spacer 7, thereby preventing any further upward movement of the inner mandrel section. After the testing or other operations in the various parts of the string have been completed, the annulus pressure is removed and the spring means inchamber 37 forces the inner mandrel system back down to its initial position by working againstpiston face 47. Upon this downward return movement, pull mandrel 5 is extended intolatch mandrel 2, thereby accomplishing the ratcheting action described beforehand. Then when another testing operation is required and the annulus pressure is again increased, the mandrels are moved upward another increment. The number of sequential pressure variations in the annulus fluid required to open the circulating valve 1 can be determined by the total length upward the latch mandrel must move to exposeports 31, divided by the incremental amount the mandrel moves during each individual pressurization of the annulus fluid. For instance in one embodiment, the latch mandrel must move ten inches toexpose the circulatingvalve ports 31 and each incremental advance is limited to one inch, therefore to actuate the circulating valve the annulus mustbe pressured ten times. This allows the annulus to be pressurized nine times to perform other testing operations through the other tools in the string without actuating the circulating valve, which preferably is opened after the completion of all testing and sampling, immediately prior to removing the test string from the well.

The number of pressure variations required to open the circulating valve can easily be varied by several methods. For instance, lengtheningspacer 7 will reduce the length of the increments and require more increments to accomplish the opening. Should it be desirable to reduce the number of increments thespacer 7 could be shortened to increase the incremental travel oflatch mandrel 2 upward.

The number of increments could also be varied by varying the distance betweenports 31 and the lower end ofskirt 21 by either moving the position ofports 31 up or down in thehousing 3 and/or varying the length of theskirt 21 extending belowports 31.

Another feature of the circulating valve of this invention is the immediate responsive opening. When the final upward increment of theskirt 21 is achieved to openports 31, the lower end ofskirt mandrel 21 is pulled out of contact with thelowermost seal 34 allowing high pressure annulus fluid to flow almost instantaneously into the space belowskirt 21 betweenhousing 3 and valve sleeve 4. This fluid is prevented from entering the bore by contact ofskirt 21 withupper seal 34 andseal 42. Thus, the high pressure fluid reacts against thebottom face 60 of the lower end of skirt 2], which face 60 acts as a differential pressure area between the high pressure annulus fluid and the relatively low pressure in theinner bore 32. This results in a slamming upward of the latch mandrel which assures a fully opened immediately responsive circulating valve.

It should be reemphasized that for proper operation of the circulating valve, springs 28 should not be any stronger than what is required to maintain latch blocks 24 in threaded engagement with pull mandrel 5 when it is moving upward. Thus, downward movement of pull mandrel 5 intolatch mandrel 2 will be possible without sliding the latch mandrel downward because the frictional retaining force ofseals 34 and 42 is substantially larger than the force required to push mandrel 5 through the latch blocks inmandrel 2.

Although a specific preferred embodiment of the present invention has been described in the detailed description above, the description is not intended to limit the invention to the particular forms or embodiments disclosed herein, since they are to be recognized as illustrative rather than restrictive and it will be obvious to those skilled in the art that the invention is not so limited. For example, while the circulating valve is described in combination with pressure operated actuating means, it is clear that other actuating means could be employed without need for modifying the circulating valve. For instance, a reciprocating actuator could replace the power section 11 and be attached to pull mandrel 5. Vertical reciprocation of the test string from the surface would serve to move the pull mandrel up and down in the latch mandrel just as the power section does with the same resulting ratcheting action which moves the mandrel out .of its covering position overports 31.

Likewise, a rotational actuating means could be utilized in conjunction with the circulating valve to movemandrel 2 upward in thehousing 3. Since the mating threads in' the latch blocks 24 and on pull mandrel 5 are preferably formed as normal helical threads, it is clear that rotating the pull mandrel by any normal means of rotation, such as for instance rotating the test string at the surface, would result in the latch mandrel being threaded upward or downward onto the pull mandrel. 6

housing 3. This limiting means would serve only to prevent rotational movement and not longitudinal axial movement of the latch mandrel. Thus, the invention is declared to cover all changes and modifications of the specific example of the invention herein disclosed for purposes of illustration, which do not constitute departures from the spirit and scope of the invention.

What is claimed is 1. Apparatus for use in testing well formations comprising:

actuating means responsive to hydraulic pressure for producing vertical, reciprocal motion for an indefinite number of times;

valve means responsive to unidirectional motion for allowing fluid communication from an annulus area exterior to a test string to an open bore within the test string after a selected number of unidirectional motions; and

means connecting said actuating means to said valve means for transferring unidirectional movement to said value means from the reciprocal movement produced by said actuating means.

2. The apparatus of claim 1 wherein said means connecting said actuating means to said valve means includes means for ratcheting said valve means from a closed position to a fully opened position in a series of sequential increments, with each sequential increment occurring in response to a vertical, reciprocal motion of said actuating means.

3. The appartus ofclaim 2 wherein said valve means includes means responsive to initial fluid communication from said annulus area to said open bore for supplying immediate opening upon performance of the last of said sequential increments.

4. The apparatus of claim 1 wherein said actuating means comprises means responsive to changes in pressure in said annulus exterior to said test string for producing vertical, reciprocal movement; said responsive means having a differential area piston means for producing vertical movement in one direction upon increases in said annulus pressure, and spring means opposing said vertical movement for producing vertical return movement in the opposite direction when said annulus pressure increases are removed.

5. The apparatus of claim 4 further comprising:

dampener means within said actuating means for preventing sudden substantial increases in annulus pressure from causing sudden vertical reciprocation of said power means, said dampener means providing an opposing force to the force of said increasing hydraulic pressure in said annulus; and

means for allowing bypass of said dampener means upon said vertical return movement of said piston means.

6. The apparatus of claim 1 wherein said valve means further comprises:

an outer tubular housing having one or more ports through the wall thereof;

an inner concentric tubular valve sleeve located within and fixedly attached to said housing;

a first mandrel slidably located between said housing ancl said sleeve and arranged in a first initial position to cover said ports and in a final position to expose said ports; and

wherein said means connecting said actuating means to said valve means further comprises:

a second mandrel arranged within said first mandrel and adapted to move vertically within said first mandrel and said housing; and

ratchet means between said first mandrel and said second mandrel for allowing said second mandrel to disengage from said first mandrel upon downward movement of said second mandrel in said first mandrel, and for latching said first mandrel to said second mandrel upon upward movement of said second mandrel.

7. The apparatus ofclaim 6 further comprising:

first travel limiting means between said second mandrel and said first mandrel for limiting the extent of total accumulated travel of said second mandrel in said first mandrel; and

second travel limiting means between said second mandrel and said tubular housing for limiting the amount of travel said second mandrel may move said first mandrel with each vertical, reciprocal motion of said actuating means.

8. A circulating valve for communicating the bore of a pipe string with the area exterior to said pipe string, said valve comprising:

a tubular cylindrical outer housing having one or more ports through the wall thereof;

means for connecting said valve between two sections of a pipe string;

inner mandrel means slidably located within said housing and arranged to sealingly cover said ports in one position and expose said ports in a second position;

pull mandrel means slidably located for reciprocal movement within said housing and connected to said inner mandrel means;

ratcheting means between said inner mandrel means and said pull mandrel means for allowing telescopic inward movement of said pu1l mandrel means with respect to said inner mandrel means, and for latching said pull mandrel means to said inner mandrel means to prevent telescopic outward movement of said pull mandrel means with respect to said inner mandrel means;

first limiting means on said pull mandrel means for limiting said inward telescopic movement of said inner mandrel means with respect to said pull mandrel means; and

second limiting means between said pull mandrel means and said housing for limiting reciprocal movement of said pull mandrel means in said hous' 9. The valve of claim 8 further comprising quick response opening means having a valve sleeve inside of said housing and said inner mandrel means, said valve sleeve being attached to said housing, differential area piston means on said inner mandrel between said housing and said valve sleeve, and seal means between said inner mandrel means, said valve sleeve, and said housing.

10. The valve of claim 8 wherein said ratcheting means further comprises:

one or more latch block openings through the wall of said inner mandrel means;

latch block means in each of said openings;

said latch block means having a curved block generally matching the curvature of said inner mandrel and having an internally grooved helical thread therein;

an externally grooved helical thread on said pull mandrel means adapted to mate with and engage said thread in said latch block means; means for preventing said latch block means from dropping inward through said openings; and

spring means for providing a continuous inward yieldable pressure against said latch block means in said openings.

11. A method of reverse circulating a displacement fluid through a string of well tools located in a closed-in well, said method comprising:

applying pressure to said displacement fluid in the annulus between said well tools and the casing of the well;

moving a first mandrel in response to said pressure application, thereby pulling a second mandrel latched to said first mandrel;

removing said annulus pressure;

unlatching said first mandrel from said second mandrel and moving said first mandrel with respect to said second mandrel in response to a means opposing movement of said first mandrel until said first mandrel has returned to its original position; repeating the above steps a predetermined number of times, thereby activating a flow means; and flowing annulus fluid through said flow means into said tool string.

Claims (11)

1. Apparatus for use in testing well formations comprising: actuating means responsive to hydraulic pressure for producing vertical, reciprocal motion for an indefinite number of times; valve means responsive to unidirectional motion for allowing fluid communication from an annulus area exterior to a test string to an open bore within the test string after a selected number of unidirectional motions; and means connecting said actuating means to said valve means for transferring unidirectional movement to said value means from the reciprocal movement produced by said actuating means.

2. The apparatus of claim 1 wherein said means connecting said actuating means to said valve means includes means for ratcheting said valve means from a closed position to a fully opened position in a series of sequential increments, with each sequential increment occurring in response to a vertical, reciprocal motion of said actuating means.

3. The appartus of claim 2 wherein said valve means includes means responsive to initial fluid communication from said annulus area to said open bore for supplying immediate opening upon performance of the last of said sequential increments.

4. The apparatus of claim 1 wherein said actuating means comprises means responsive to changes in pressure in said annulus exterior to said test string for producing vertical, reciprocal movement; said responsive means having a differential area piston means for producing vertical movement in one direction upon increases in said annulus pressure, and spring means opposing said vertical movement for producing vertical return movement in the opposite direction when said annulus pressure increases are removed.

5. The apparatus of claim 4 further comprising: dampener means within said actuating means for preventing sudden substantial increases in annulus pressure from causing sudden vertical reciprocation of said power means, said dampener means providing an opposing force to the force of said increasing hydraulic pressure in said annulus; and means for allowing bypass of said dampener means upon said vertical return movement of said piston means.

6. The apparatus of claim 1 wherein said valve means further comprises: an outer tubular housing having one or more ports through the wall thereof; an inner concentric tubular valve sleeve located within and fixedly attached to said housing; a first mandrel slidably located between said housing and said sleeve and arranged in a first initial position to cover said ports and in a final position to expose said ports; and wherein said means connecting said actuating means to said valve means further comprises: a second mandrel arranged within said first mandrel and adapted to move vertically within said first mandrel and said housing; and ratchet means between said first mandrel and said second mandrel for allowing said second mandrel to disengage from said first mandrel upon downward movement of said second mandrel in said first mandrel, and for latching said first mandrel to said second mandrel upon upward movement of said second mandrel.

7. The apparatus of claim 6 further comprising: first travel limiting means between said second mandrel and said first mandrel for limiting the extent of total accumulated travel of said second mandrel in said first mandrel; and second travel limiting means between said second mandrel and said tubular housing for limiting the amount of travel said second mandrel may move said first mandrel with each vertical, reciprocal motion of said actuating means.

8. A circulating valve for communicating the bore of a pipe string with the area exterior to said pipe string, said valve comprising: a tubular cylindrical outer housing having one or more ports through the wall thereof; means for connecting said valve between two sections of a pipe string; inner mandrel means slidably located within said housing and arranged to sealingly cover said ports in one position and expose said ports in a second position; pull mandrel means slidably located for reciprocal movement within said housing and connected to said inner mandrel means; ratcheting means between said inner mandrel means and said pull mandrel means for allowing telescopic inward movement of said pull mandrel means with respect to said inner mandrel means, and for latching said pull mandrel means to said inner mandrel means to prevent telescopic outward movement of said pull mandrel means with respect to said inner mandrel means; first limiting means on said pull mandrel means for limiting said inward telescopic movement of said inner mandrel means with respect to said pull mandrel means; and second limiting means between said pull mandrel means and said housing for limiting reciprocal movement of said pull mandrel means in said housing.

9. The valve of claim 8 further comprising quick response opening means having a valve sleeve inside of said housing and said inner mandrel means, said valve sleeve being attached to said housing, differential area piston means on said inner mandrel between said housing and said valve sleeve, and seal means between said inner mandrel means, said valve sleeve, and said housing.

10. The valve of claim 8 wherein said ratcheting means further comprises: one or more latch block openings through the wall of said inner mandrel means; latch block means in each of said openings; said latch block means having a curved block generally matching the curvature of said inner mandrel and having an internally grooved helical thread therein; an externally grooved helical thread on said pull mandrel means adapted to mate with and engage said thread in said latch block means; means for preventing said latch block means from dropping inward through said openings; and spring means for providing a continuous inward yieldable pressure against said latch block means in said openings.

11. A method of reverse circulating a displacement fluid through a string of well tools located in a closed-in well, said method comprising: applying pressure to said displacement fluid in the annulus between said well tools and the casing of the well; moving a first mandrel in response to said pressure application, thEreby pulling a second mandrel latched to said first mandrel; removing said annulus pressure; unlatching said first mandrel from said second mandrel and moving said first mandrel with respect to said second mandrel in response to a means opposing movement of said first mandrel until said first mandrel has returned to its original position; repeating the above steps a predetermined number of times, thereby activating a flow means; and flowing annulus fluid through said flow means into said tool string.

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