US3768562A — Full opening multiple stage cementing tool and me…

Claim 1

Independent Claim 176 words

A full opening cementing tool for multiple stage oil well cementing comprising: a. an outer cylindrical housing having a plurality of ports through the wall; b. a valve sleeve located telescopically within said housing and having a plurality of ports through the wall capable of fluidically communicating with said ports in said housing in a first open position and fluidically sealed from said housing ports in a second closed position; c. spring tension means between said housing and said sleeve for preventing premature or unwanted movement of said sleeve in said housing; d. means attached to said housing for inserting said housing into a standard casing string; e. first means for engaging said sleeve and moving said sleeve from said first position to said second position; and f. second means for engaging said sleeve and moving said sleeve from said second position to said first position, said first and second means for engaging said sleeve being fixedly attached to a drill string or tubing string located concentrically within said sleeve and telescopically movable within said sleeve.

Claim 2

Dependent Claim 176 words

A full opening cementing tool for multiple stage oil well cementing comprising: a. an outer cylindrical housing having a plurality of ports through the wall; b. a valve sleeve located telescopically within said housing and having a plurality of ports through the wall capable of fluidically communicating with said ports in said housing in a first open position and fluidically sealed from said housing ports in a second closed position; c. spring tension means between said housing and said sleeve for preventing premature or unwanted movement of said sleeve in said housing; d. means attached to said housing for inserting said housing into a standard casing string; e. first means for engaging said sleeve and moving said sleeve from said first position to said second position; and f. second means for engaging said sleeve and moving said sleeve from said second position to said first position, said first and second means for engaging said sleeve being fixedly attached to a drill string or tubing string located concentrically within said sleeve and telescopically movable within said sleeve.

Claim 3

Dependent Claim 63 words

The cementing tool of claim 1 wherein said tool further comprises seal means between said housing and said sleeve arranged to prevent fluid communication between the walls of said housing and said sleeve, and said housing further having an inner annular circumferential recess communicating with said ports in said housing and an inner annular ridge having sloping walls and located inside said housing.

Claim 4

Dependent Claim 101 words

The cementing tool of claim 2 wherein said sleeve further has a first inner annular recess in said sleeve, having a sloping side wall, a perpendicular side wall, and a circumferentially coaxial wall; a second inner annular recess having a sloping side wall, a perpendicular side wall, and a circumferential coaxial wall; a beveled end at one end of said sleeve; a skirt at the opposite end of said sleeve, said skirt being formed by an enlargement in the bore through said sleeve; and an outer annular recess in said sleeve arranged to receive said inner annular ridge in said housing.

Claim 5

Dependent Claim 71 words

The cementing tool of claim 1 wherein said spring tension means comprises a plurality of collet fingers located around one end of said sleeve, an inner annular ridge on said housing, an inner annular recess in said housing between said ridge and said means for inserting said housing into a casing string; with said collet fingers having an outer annular ridge adapted to abut said ridge and fit within said recess.

Claim 6

Dependent Claim 104 words

The cementing tool of claim 1 wherein said spring tension means comprises one or more circular rings made of an elastic metal and located within an outer annular recess in said sleeve, said rings adapted to project outward from said sleeve and being capable of being contracted sufficiently to place the outer surface of said rings flush with the outer surface of said sleeve; said housing having two inner annular recesses having sloping walls, one of said recesses adapted to receive said rings in a closed sleeve position and the other of said recesses adapted to receive said rings in an open sleeve position.

Claim 7

Dependent Claim 74 words

The cementing tool of claim 1 wherein said first and second means for engaging said sleeve each comprises a plurality of spring arms integrally attached to a spring collar, said spring collar encircling and fixedly attached to a spring mandrel, said spring mandrel containing a plurality of shielding drag lugs, one for each said spring arm, and said spring mandrel being adapted to be interposed between two sections of standard drill pipe or tubing.

Claim 8

Dependent Claim 106 words

The cementing tool of claim 6 wherein said spring arms each contain a perpendicular shoulder capable of and adapted to engage a mating perpendicular shoulder within said sleeve and also adapted to transmit sufficient force to said sleeve to move said sleeve within said housing from an open to a closed position and from a closed to an open position; and said spring arms each furthEr comprise an outer shoulder arranged to engage an inward projecting shoulder in said means for inserting said housing in a casing string, said shoulder arranged to disengage said spring arms from said sleeve after moving said sleeve a predetermined distance.

Claim 9

Dependent Claim 196 words

Oil well cementing apparatus capable of cementing any number of annulus cementing stages and adapted to be interposed between sections of oil well casing comprising: a. one or more sliding sleeve cementing valves adapted to be interconnected within a casing string, each said valve comprising ported sliding inner sleeve means and a ported stationary outer housing, said sleeve valves each being movable from a closed position to an open position and from an open position to a closed position an indefinite number of times, each said valve adapted to be placed one at each cementing stage location; b. opening means adapted to be arranged axially on a drill string or tubing string to be moved telescopically within the casing and through said cementing valves, said opening means adapted to engage said inner sleeve means so as to move said inner sleeve means to a valve-open position; and c. closing means adapted to be arranged axially on a drill string or tubing string, to be moved telescopically within the casing and through said cementing valves, said closing means adapted to engage said inner sleeve means so as to move said inner sleeve means to a valve-closed position.

Claim 10

Dependent Claim 196 words

Oil well cementing apparatus capable of cementing any number of annulus cementing stages and adapted to be interposed between sections of oil well casing comprising: a. one or more sliding sleeve cementing valves adapted to be interconnected within a casing string, each said valve comprising ported sliding inner sleeve means and a ported stationary outer housing, said sleeve valves each being movable from a closed position to an open position and from an open position to a closed position an indefinite number of times, each said valve adapted to be placed one at each cementing stage location; b. opening means adapted to be arranged axially on a drill string or tubing string to be moved telescopically within the casing and through said cementing valves, said opening means adapted to engage said inner sleeve means so as to move said inner sleeve means to a valve-open position; and c. closing means adapted to be arranged axially on a drill string or tubing string, to be moved telescopically within the casing and through said cementing valves, said closing means adapted to engage said inner sleeve means so as to move said inner sleeve means to a valve-closed position.

Claim 11

Dependent Claim 73 words

The apparatus of claim 8 further comprising: a. isolation packer means located on the drill string and in close proximity to said opening and closing means; b. circulating valve means on the drill string capable of providing fluid communication from the interior of the drill string tubing to the annulus between the drill string and the casing; and c. means for sealing the bottom end of the drill string against fluid flow therethrough.

Claim 12

Dependent Claim 81 words

The apparatus of claim 9 wherein said isolation packer means comprises an upper packer and a lower packer, said upper packer having two annular elastomeric cups, one said cup being concave upward and one said cup being concave downward; said lower packer having one elastomeric cup, which cup is concave upward and said upper and lower packers adapted to fluidically seal off a cross section of the casing against fluid flowing from the direction of concavity of each said elastomeric cup.

Claim 13

Dependent Claim 112 words

The apparatus of claim 10 wherein said opening means is located above said closing means on the drill string, said upper packer is located on the drill string between said opening and said closing means, said lower packer is located below said closing means on the drill string, said circulating valve is located below said lower packer; and said isolation packer means further comprises a tubular mandrel body to which said elastomeric cups are attached, said mandrel body having ports therethrough capable of communicating fluidically between the inner bore of said tubular mandrel and the annulus between the tubing string and the casing, said ports located directly below said upper packer cups.

Claim 14

Dependent Claim 72 words

The apparatus of claim 11 wherein said tubular mandrel body further comprises a packer bypass channel within the wall of said mandrel body providing fluid communication from the annulus area above said upper packer to the annulus area below said lower packer, and said circulating valve means is adapted to be actuated by remote control from ground surface to provide pressure balance when coming out of the hole with the drill string.

Claim 15

Dependent Claim 65 words

The apparatus of claim 8 further comprising spring tension means in said sliding sleeve cementing valves adapted to prevent opening or closing of said valves until a certain predetermined tensile or compressive force is applied to said inner sleeve means, and seal means between said sleeve means and each of said housings preventing fluid flow between the walls of said sleeve means and said housings.

Claim 16

Independent Claim 326 words

A method of cementing the outer casing annulus of a well borE in any desired number of stages wherein the casing in the well bore has a predetermined number of casing valves located in the casing wall in preset locations therein; said method comprising: a. flowing a precalculated quantity of cement slurry down the interior of the well casing, out the bottom of the casing and back up the annulus between the casing and the well bore; b. inserting a wiper plug in the casing immediately behind said cement slurry; c. pumping a working fluid behind the wiper plug, said fluid having the consistency and specific gravity near that of the cement slurry, thereby forcing the wiper plug and cement slurry to the bottom of the casing; d. applying pressure to said working fluid until the wiper plug seats in sealing engagement in the bottom of the casing thereby causing an indicative rise in fluid pressure in the casing; e. running in a string of tubular pipe in the well casing, said string of pipe having an opening positioner and a closing positioner located thereon; f. engaging said opening positioner in the lowermost of said casing valves and thereby opening said valve and providing fluid communication channels between the annulus inside the casing to the annulus outside the casing; g. pumping a second predetermined quantity of cement slurry down the interior of the pipe string and out the bottom end of the pipe, whereby said second slurry flows through said casing valve and into the second stage of the exterior casing annulus; h. engaging said closing positioner in said lowermost casing valve and thereby closing said valve against additional fluid flow; i. lifting the string of pipe to the next adjacent area of the casing to be cemented, which area contains another casing valve; and j. repeating said steps (f) through (i) above until all stages of cementing in the exterior casing annulus have been completed.

Claim 17

Independent Claim 326 words

A method of cementing the outer casing annulus of a well borE in any desired number of stages wherein the casing in the well bore has a predetermined number of casing valves located in the casing wall in preset locations therein; said method comprising: a. flowing a precalculated quantity of cement slurry down the interior of the well casing, out the bottom of the casing and back up the annulus between the casing and the well bore; b. inserting a wiper plug in the casing immediately behind said cement slurry; c. pumping a working fluid behind the wiper plug, said fluid having the consistency and specific gravity near that of the cement slurry, thereby forcing the wiper plug and cement slurry to the bottom of the casing; d. applying pressure to said working fluid until the wiper plug seats in sealing engagement in the bottom of the casing thereby causing an indicative rise in fluid pressure in the casing; e. running in a string of tubular pipe in the well casing, said string of pipe having an opening positioner and a closing positioner located thereon; f. engaging said opening positioner in the lowermost of said casing valves and thereby opening said valve and providing fluid communication channels between the annulus inside the casing to the annulus outside the casing; g. pumping a second predetermined quantity of cement slurry down the interior of the pipe string and out the bottom end of the pipe, whereby said second slurry flows through said casing valve and into the second stage of the exterior casing annulus; h. engaging said closing positioner in said lowermost casing valve and thereby closing said valve against additional fluid flow; i. lifting the string of pipe to the next adjacent area of the casing to be cemented, which area contains another casing valve; and j. repeating said steps (f) through (i) above until all stages of cementing in the exterior casing annulus have been completed.

Claim 18

Independent Claim 337 words

A method of cementing the annulus between a well casing and the well bore hole in a plurality of separate distinct stages wherein the casing contains a casing valve for each stage to be cemented, said casing valves being interposed between sections of casing in predetermined locations; the method comprising the steps of: a. inserting a string of pipe within the casing into fluidically sealed engagement with the lower end of the casing, said string of pipe having an internal bore passage communicating through the bottom of the casing, said sealed engagement serving to close off the bottom of the annulus area between the pipe and the casing, said string of pipe also having valve opening means and valve closing means attached exteriorly thereto; b. pumping a predetermined quantity of cement slurry through the pipe string inner bore, out the bottom of the casing, and up the annulus between the casing and the well bore; c. placing a latch-down plug in the pipe behind said cement slurry; d. pumping into the pipe behind said plug a working fluid having a specific gravity similar to that of the cement slurry, thereby forcing said plug down the pipe string into latching engagement with the bottom of the casing, thereby effecting a seal across the entire casing passage at the bottom; e. lifting the pipe string partially out of the casing until said opening means engages and opens the lowermost of said casing valves and the bottom of the pipe string is slightly above the opened valve; f. pumping a second predetermined quantity of cement slurry down the pipe bore and through the opened casing valve into the exterior casing annulus thereby effecting a cementing of the second stage; g. engaging said closing means in said casing valve thereby closing the valve; h. lifting the pipe string to the next adjacent casing valve at the next stage to be cemented; and i. repeating said steps (e) through (h) above until the entire annular area to be cemented has been cemented.

Claim 19

Independent Claim 337 words

A method of cementing the annulus between a well casing and the well bore hole in a plurality of separate distinct stages wherein the casing contains a casing valve for each stage to be cemented, said casing valves being interposed between sections of casing in predetermined locations; the method comprising the steps of: a. inserting a string of pipe within the casing into fluidically sealed engagement with the lower end of the casing, said string of pipe having an internal bore passage communicating through the bottom of the casing, said sealed engagement serving to close off the bottom of the annulus area between the pipe and the casing, said string of pipe also having valve opening means and valve closing means attached exteriorly thereto; b. pumping a predetermined quantity of cement slurry through the pipe string inner bore, out the bottom of the casing, and up the annulus between the casing and the well bore; c. placing a latch-down plug in the pipe behind said cement slurry; d. pumping into the pipe behind said plug a working fluid having a specific gravity similar to that of the cement slurry, thereby forcing said plug down the pipe string into latching engagement with the bottom of the casing, thereby effecting a seal across the entire casing passage at the bottom; e. lifting the pipe string partially out of the casing until said opening means engages and opens the lowermost of said casing valves and the bottom of the pipe string is slightly above the opened valve; f. pumping a second predetermined quantity of cement slurry down the pipe bore and through the opened casing valve into the exterior casing annulus thereby effecting a cementing of the second stage; g. engaging said closing means in said casing valve thereby closing the valve; h. lifting the pipe string to the next adjacent casing valve at the next stage to be cemented; and i. repeating said steps (e) through (h) above until the entire annular area to be cemented has been cemented.

Claim 20

Independent Claim 441 words

A method of cementing the annulus between a well casing and a well bore hole iN a plurality of distinct and separate stages wherein the casing contains a casing valve for each stage to be cemented, said casing valves being interposed between sections of casing in predetermined locations; the method comprising the steps of: a. pumping a precalculated quantity of cement slurry down the interior of the casing, out the bottom of the casing, and back up the annulus between the casing and the well bore; b. inserting a wiper plug in the casing immediately behind the cement slurry; c. pumping a working fluid behind the wiper plug, said fluid having similar specific gravity to that of the cement, thereby forcing the wiper plug and cement slurry to the bottom of the casing, forcing all of the cement into the annulus, and sealingly engaging the wiper plug in the bottom end of the casing; d. running in a string of pipe in the casing, said string of pipe containing casing valve opening means, upper isolation packer means below said valve opening means, cementing ports through the pipe wall below said upper packer means, casing valve closing means below said cementing ports, lower packer means below said valve closing means, seal means closing off the lower end of the drill pipe, fluid bypass means providing fluid communication from the annular area above said upper packer means to the annular area below said lower packer means, and circulating valve means in said pipe for providing fluid communication between the internal pipe bore and the casing bore, and being opened only when coming out of the hole with the pipe string; e. engaging said valve opening means in the lowermost of said valves in the lowermost uncemented stage thereby opening said valve and providing fluid communication through the casing; f. aligning said cementing ports in the pipe with said opened casing valve; g. pumping another predetermined amount of cement slurry into the pipe string, out the cementing ports in the pipe below said upper packer, and through the casing valve into the area of outer casing annulus to be cemented during this stage; h. engaging said closing means in said opened casing valve by lifting up and then setting down on the pipe string sufficiently enough to move said closing means upward and downward through said valve, thereby closing said valve; i. lifting the pipe string to align the opening means with the next upper adjacent casing valve in order to accomplish the next cementing stage; and j. repeating the above said steps (e) through (i) until all desired cementing stages have been completed.

Claim 21

Independent Claim 441 words

A method of cementing the annulus between a well casing and a well bore hole iN a plurality of distinct and separate stages wherein the casing contains a casing valve for each stage to be cemented, said casing valves being interposed between sections of casing in predetermined locations; the method comprising the steps of: a. pumping a precalculated quantity of cement slurry down the interior of the casing, out the bottom of the casing, and back up the annulus between the casing and the well bore; b. inserting a wiper plug in the casing immediately behind the cement slurry; c. pumping a working fluid behind the wiper plug, said fluid having similar specific gravity to that of the cement, thereby forcing the wiper plug and cement slurry to the bottom of the casing, forcing all of the cement into the annulus, and sealingly engaging the wiper plug in the bottom end of the casing; d. running in a string of pipe in the casing, said string of pipe containing casing valve opening means, upper isolation packer means below said valve opening means, cementing ports through the pipe wall below said upper packer means, casing valve closing means below said cementing ports, lower packer means below said valve closing means, seal means closing off the lower end of the drill pipe, fluid bypass means providing fluid communication from the annular area above said upper packer means to the annular area below said lower packer means, and circulating valve means in said pipe for providing fluid communication between the internal pipe bore and the casing bore, and being opened only when coming out of the hole with the pipe string; e. engaging said valve opening means in the lowermost of said valves in the lowermost uncemented stage thereby opening said valve and providing fluid communication through the casing; f. aligning said cementing ports in the pipe with said opened casing valve; g. pumping another predetermined amount of cement slurry into the pipe string, out the cementing ports in the pipe below said upper packer, and through the casing valve into the area of outer casing annulus to be cemented during this stage; h. engaging said closing means in said opened casing valve by lifting up and then setting down on the pipe string sufficiently enough to move said closing means upward and downward through said valve, thereby closing said valve; i. lifting the pipe string to align the opening means with the next upper adjacent casing valve in order to accomplish the next cementing stage; and j. repeating the above said steps (e) through (i) until all desired cementing stages have been completed.

Claim 22

Dependent Claim 95 words

The method of claim 16 further comprising the step of reversing out after each cementing stage the excess cement slurry remaining between said upper and lower packer means and in the pipe string, said reversing out comprising pumping a working fluid into the annulus between the pipe and casing, through the fluid bypass means into the annular area below the lower packer means, and up past the lower packer means, thereby forcing the excess cement through the cementing ports in the pipe and up the bore of the pipe in front of the working fluid.

Claim 23

Dependent Claim 27 words

The method of claim 17 further comprising the steps of opening said circulating valve by manipulation from the surface and removing said pipe string from the borehole.

Claim 24

Independent Claim 471 words

A method of cementing the annulus between a well casing and a well bore hole in a plurality of distinct and separate stages wherein the casing contains a casing valve for each stage to be cemented, said casing valves being interposed between sections of casing in predetermined locations, the method comprising the steps of: a. running in a string of pipe in the casing, said string of pipe containing casing valve opening means, upper isolation packer means below said valve opening means, cementing ports through the pipe wall immediately below said upper packer means, casing valve closing means below said cementing ports, lower packer means below said valve closing means, fluid bypass means providing fluid communication from the annular area above said upper packer means to the annular area below said packer means, and circulating valve means in said pipe for providing fluid communication between the pipe bore and the casing bore when said pipe string is coming out of the well; b. engaging said pipe string in a sealing adapter in the bottom of the casing thereby sealing off the annulus between the pipe and the casing while maintaining a clear passage from the bore of the pipe through the bottom of the casing; c. pumping a first latch plug down the pipe to sealingly engage in the float shoe; d. pumping a predetermined quantity of cement slurry behind the first latch plug, down the pipe, through the bottom of the casing, and back up the annulus; e. inserting a second plug in the pipe immediately behind the cement slurry; f. pumping working fluid into the pipe behind the second plug, said fluid having a similar specific gravity to that of the cement slurry, thereby forcing the second plug and cement slurry to the bottom of the pipe, forcing all of the cement into the exterior casing annulus and sealingly engaging the second plug in the bottom end of the pipe; g. engaging said valve opening means in the lowermost of said valves in the lowermost uncemented stage thereby opening said valve and providing fluid communication through the casing; h. aligning said cementing ports in the pipe with said opened casing valve; i. closing said circulating valve means; j. pumping another predetermined amount of cement slurry into the pipe string, out the cementing ports in the pipe and through the casing valve into the area of outer casing annulus to be cemented during this stage; k. engaging said closing means in said casing valve by appropriately manipulating the pipe string, thereby closing said casing valve; l. lifting up on the pipe string to bring the opening means to the next upper adjacent casing valve in order to begin the next cement stage; and m. repeating the above said steps (g) through (l) until all desired cementing stages have been completed.

Claim 25

Independent Claim 471 words

A method of cementing the annulus between a well casing and a well bore hole in a plurality of distinct and separate stages wherein the casing contains a casing valve for each stage to be cemented, said casing valves being interposed between sections of casing in predetermined locations, the method comprising the steps of: a. running in a string of pipe in the casing, said string of pipe containing casing valve opening means, upper isolation packer means below said valve opening means, cementing ports through the pipe wall immediately below said upper packer means, casing valve closing means below said cementing ports, lower packer means below said valve closing means, fluid bypass means providing fluid communication from the annular area above said upper packer means to the annular area below said packer means, and circulating valve means in said pipe for providing fluid communication between the pipe bore and the casing bore when said pipe string is coming out of the well; b. engaging said pipe string in a sealing adapter in the bottom of the casing thereby sealing off the annulus between the pipe and the casing while maintaining a clear passage from the bore of the pipe through the bottom of the casing; c. pumping a first latch plug down the pipe to sealingly engage in the float shoe; d. pumping a predetermined quantity of cement slurry behind the first latch plug, down the pipe, through the bottom of the casing, and back up the annulus; e. inserting a second plug in the pipe immediately behind the cement slurry; f. pumping working fluid into the pipe behind the second plug, said fluid having a similar specific gravity to that of the cement slurry, thereby forcing the second plug and cement slurry to the bottom of the pipe, forcing all of the cement into the exterior casing annulus and sealingly engaging the second plug in the bottom end of the pipe; g. engaging said valve opening means in the lowermost of said valves in the lowermost uncemented stage thereby opening said valve and providing fluid communication through the casing; h. aligning said cementing ports in the pipe with said opened casing valve; i. closing said circulating valve means; j. pumping another predetermined amount of cement slurry into the pipe string, out the cementing ports in the pipe and through the casing valve into the area of outer casing annulus to be cemented during this stage; k. engaging said closing means in said casing valve by appropriately manipulating the pipe string, thereby closing said casing valve; l. lifting up on the pipe string to bring the opening means to the next upper adjacent casing valve in order to begin the next cement stage; and m. repeating the above said steps (g) through (l) until all desired cementing stages have been completed.

Claim 26

Dependent Claim 92 words

The method of claim 19 further comprising reversing out after each cementing stage the excess cement slurry remaining between said upper and lower packer means and in the pipe string, said reversing out comprising pumping a working fluid into the annulus between the pipe and casing, through the fluid bypass means into the annular area below the lower packer means, and up past the lower packer means thereby forcing the excess cement through the cementing ports in the pipe and up the bore of the pipe in front of the working fluid.

Claim 27

Dependent Claim 180 words

A tool for passing inside a sleeve valve to selectively open and close said sleeve valve, comprising: a. tubular body means adapted to be connected to a string of pipe and passed axially into the sleeve valve; b. first collar means encircling said body means and snugly attached thereto; c. second collar means encircling said body means and attached thereto, below said first collar means; d. a plurality of first spring arms attached to said first collar means, and adapted to engage said sleeve valve when closed and move said sleeve valve into an open position when passing in one direction therethrough; e. a plurality of second spring arms attached to said second collar means, and adapted to engage said sleeve valve when open and move said sleeve valve into a closed position when passing in one direction therethrough; f. means on said first spring arms for disengaging said first spring arms after said sleeve valve has been opened; and g. means on said second spring arms for disengaging said second spring arms after said sleeve valve has been closed.

Claim 28

Dependent Claim 180 words

A tool for passing inside a sleeve valve to selectively open and close said sleeve valve, comprising: a. tubular body means adapted to be connected to a string of pipe and passed axially into the sleeve valve; b. first collar means encircling said body means and snugly attached thereto; c. second collar means encircling said body means and attached thereto, below said first collar means; d. a plurality of first spring arms attached to said first collar means, and adapted to engage said sleeve valve when closed and move said sleeve valve into an open position when passing in one direction therethrough; e. a plurality of second spring arms attached to said second collar means, and adapted to engage said sleeve valve when open and move said sleeve valve into a closed position when passing in one direction therethrough; f. means on said first spring arms for disengaging said first spring arms after said sleeve valve has been opened; and g. means on said second spring arms for disengaging said second spring arms after said sleeve valve has been closed.

Claim 29

Dependent Claim 167 words

The tool of claim 21 further comprising: a. upper packing means comprising two upper back-to-back concave elastomeric sealing cups located circumferentially on said tubular body means between said first and second collar means; b. lower packIng means comprising a lower concave elastomeric sealing cup located circumferentially on said tubular body below said second collar means and adapted so that the concave portion of said lower sealing cup faces said upper packing means; c. said tubular body having cementing ports passing through the wall thereof and located between said upper packing means and said second collar means, in close proximity to said upper packing means; d. said tubular body having fluid bypass means adapted to fluidically communicate the exterior of said tubular body above said upper packing means to the exterior of said tubular body below said lower packing means; and e. means for sealing the bore passage through said tubular body, said means adapted for sealing the ends of said tubular body below said lower packing means.

Claim 30

Dependent Claim 42 words

The tool of claim 22 further comprising circulating valve means located on said tubular body wall below said lower packing means and adapted to selectively provide fluid communication from the interior of said tubular body to the exterior of said tubular body.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1976-10-29	1977-04-30	1977-10-30	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1980-10-29	1981-04-30	1981-10-30	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1984-10-29	1985-04-30	1985-10-30	$7700.00	Window Closed / Lapsed

Full opening multiple stage cementing tool and methods of use

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