US2997107A - Well packer confining means - Google Patents

Description

Aug. 22, 1961 .1. LYNES WELL PACKER CONFINING MEANS 5 Sheets-$heet 1 Filed Feb. 24, 1958 INVENTOR:

JOHN LVNES FIG. 1

FIGJA FIG. 1B

m M m T A Aug. 22, 1961 J. LYNES WELL PACKER CONFINING MEANS 5 Sheets-Sheet 2 Filed Feb. 24, 1958 B IIIIIIw 1IIII FIG. 3

INVENTOR:

JOHN LYNES V law 2,- L

ATTORNEYS 5 Sheets-Sheet 3 J. LYNES WELL PACKER CONFINING MEANS FIG. 6

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ATTORNEK? Aug. 22, 1961 J. LYNES WELL PACKER CONFINING MEANS 5 Sheets-Sheet 4 Filed Feb. 24, 1958 INVENTOR: JOHN LVNES W MzrA A TTORNEVS Aug. 22,. 1961 J. LYNES WELL PACKER CONFINING MEANS 5 Sheets-Sheet 5 Filed Feb. 24, 1958 INVENTOR:

JOHN LVNES mam & Lewis,

A TTORNEVS United States Patent 2,997,107 WELL PACKER CONFINING MEANS John Lynes, Albuquerque, N. Mex., assignor to Oil Recovery Corporation, Denver, Colo., a corporation of Colorado Filed Feb. 24, 1958, Ser. No. 717,066 Claims. (Cl. 166204) This invention relates to an improved well packer for oil and gas Wells. 4

Such devices are attached to the ends of drill strings or tubings and include one or more flexible packer members which are caused to expand into contact with the walls of a well to seal off a selected portion thereof from any fluid present in .the Well. Thereupon, various operations are performed, such as taking test samples from the sealed-01f strata, or treating said strata by injection of fluids to enhance productivity.

Packer tools must be operated at great depths and are subjected to extreme conditions of very high pressures which may approximate many thousands of pounds per square inch in the case of deep wells where there exists the usual fluid column of thousands of feet above the packer, the column consisting of water, oil or drilling mud.

The principal object of the invention is therefore to provide packer means which will form an elfective seal in a well and is capable of withstanding the tremendous pressure differentials which occur by reason of the seal during treating or twisting operations.

According to the invention, I provide a specially designed flexible packer element and, in combination with it, confining means in the form of a collapsible seat which in operative position prevents rupture or movements of the packer element so that it is preserved in an efiective position to provide the positive seal for which it is intended.

' Other objects of the invention are to provide packer devices which are simply and surely operated from the surface, and which are designed to prevent damage to the well, as by becoming jammed therein. In this respect a packer tool is provided which is of small diameter but has a remarkably high ratio of expansion. I

Further objects of the invention will be described in connection with the drawings, wherein the invention is described in connection with two types of packer tools of my invention, a tool with a single packer element (FIGS. 1 and 2) and a dual packer tool (FIGS. 3-8.)

In the drawing:

FIG. 1 is an elevation, with parts in section, of a dry stem testing tool, employing a single packer, shown in collapsed condition, as it would remain on lowering into a well;

FIG. 1A is a section taken on lies lA--1A of FIG. 1;

FIG. 1B is a perspective'detail of part of the nipple with flange and lug at approximately the location of FIG. 1A;

FIG. 2 is a similar view of the tool of FIG. 1, in operative position forming a seal in a well;

FIGS. 3-4 are elevations with parts in section, of the top and bottom sections of a two-packer tool in collapsed, or lowering-in position;

FIGS. 5-6 are similar views of the same tool in operative or expanded position in a well, forming two seals therein;

FIGS. 7 and 8 are enlarged views of one of the packer elements of FIGS. 3-6, showing details of its construction and of its collapsible seat or confining means;

FIGS. 9 and 10 are enlarged sectional details of the collapsible packer seat in collapsed and in operative position, respectively; and a FIG. 11 is an enlarged perspective detail of the collapsible seat per se, in operative position.

The tool shown in FIGS. 12 incorporating my invention, is termed a dry steam testing tool, a type which employs a single packer. When this packer is operated to form a seal, the tool is opened to withdraw a fluid sample from formations beneath the packer.

This tool consists of a hollow telescopic body member composed of an upper head 20 carrying an internally threaded mandrel or connection 21, having an enlarged flange 22 at its lower extremity which is housed in the lower hollow body member 23. Member 23 is slidably mounted on mandrel 21, and has an internal upper flange 24 abutting flange 22 in the FIG. 1 lowering-in position, flange 22 thus supporting member 23.

Lower body member 23 carries teeth 25 'for engagement with the well bottom, and testing ports 26 for the entry of a fluid sample when the tool is in the FIG. 2 operative position. Member 23 may be of various lengths to suit the selected depth for testing, or may be formed in threaded sections to locate the flexible packer at the desired distance from the well bottom.

The upper head member 20 has an internal recess carrying a sealing ring 27 diagonally disposed therein, according to the invention disclosed in my Patent 2,738,016, dated March 13, 1956.

The tool is supported from a pipe string, not shown,

which connects to nipple 28 rotatably carried internally of head member 20. Nipple 28 has an annular supporting flange 29 which is seated in a circular slot 30, slot 30 being formed between head 20 and its upper screw cap 80. Flange 29 is formed with a depending lug 81 rotatable within the confines of semicircular slot 82 formed in head 20 beneath slot 30. This construction is shown in detail in FIGS. 1A and 1B. Nipple 28 is further provided with a port 31 located centrally of sealing ring 27, the latter, as previously stated, being located diagonally in the tool. Due to this arrangement, as will be further described, when port 31 is in the FIG. 1 position it is closed with respect to any fluid contained in mandrel 21, and when it is in the FIG. 2 position, it is below the ring 27 and hence open to the interior of the tool beneath nipple 28. Nipple 28 is further provided with a closed lower tip extending into mandrel 21. Cap carries a sealing ring identified at 83.

l A spiral spring 32 with its upper end welded to nipple 28 and its lower end welded to cap 80, is stressed to hold nipple 28 in the position shown in FIG. 1, with respect to the head 20. Lug 81 is thus thrust to the right, or in the position shown in FIG. 1A.

At the lower end of body 20 is threaded a collar 33 to the inner periphery of which is firmly attached, as by vulcanizin-g, the upper end of a flexible packer member 35, further to be described in detail. The confining means, or collapsible seat 40, is carried around mandrel 21 and separates packer 35 from body member 23. Seat 40 rests on the flange 24 of member 23. Details of the seat 40 will be described below.

The general operation of the tool of FIGS. 1-2 will now be described. In the collapsed position, FIG. 1, the tool is lowered into the well with packer 35 and seat 40 collapsed. Also by virtue of spring 32, port 31 is in the closed position to the right of seal 27. A small amount of well fluid may enter the tool, as indicated by the flow arrow, FIG. 1, but may not enter nipple 28. Nipple 28 and its supporting pipe thus remain in a dry state, ready to receive a fluid sample.

When the tool reaches the well bottom, as seen in FIG. 2, the member 23 is immobilized from rotation by the engagement of teeth 25. Further lowering of the tool causes mandrel 21 to telescope into the body'member 1 23, upon which the collapsible seat 40 will spring open into actual or approximate contact with the well walls. Thereafter, the continued lowering of mandrel 21 will telescope packer 35 causing it to expand laterally into firm engagement with the well walls in the manner depicted in FIG. 2.

With packer 35 on set position, and connected, as above noted, to head by means of collar 33, no movement of head 20, vertically or rotationally, is possible. The tool is then in a condition for nipple 28 to be rotated relative to head 20.

With the tool in this condition, a clockwise rotation of the drill string at the surface will rotate nipple 28 relative to the rest of the tool, overcoming the action of spring 32 while applying torque thereto and moving port 31 to the left-hand position shown in FIG. 2, or beneath the sealing ring 27, whereupon well fluid from below packer 35 may enter, or be pumped into, nipple 28 via port 31, thence to the surface, as indicated by the flow arrow at the top of FIG. 2.

To deactivate the packer, the drill string is lifted. As this is done, teeth are disengaged, and the packer member and seat will collapse and return to the FIG. 1 position. In this position, spring 32 is once again able to exert its force and move the head 20 and the rest of the tool counterclockwise relative to nipple 28, closing valve 31 by moving it above sealing ring 27, likewise as shown in FIG. 1. Accordingly, any fluid sample is effectively trapped in the nipple 28, and may be secured by drawing the tool from the well.

In FIGS. 3-6, the invention is shown in conjunction with a two packer type tool of my invention similar to that of my aforesaid Patent 2,738,016, designed to seal off or straddle a formation at any selected well depth.

In these views, FIGS. 3 and 4 show the top and bottom of the tool in collapsed condition; FIGS. 5 and 6 the top and bottom of the tool in operative condition.

In these views an inner supporting pipe 50, jointed at 51, FIGS. 4 and 6, runs the length of the tool and supports each packer assembly by connection to its upper housings 52-53. This connection is similar to that described for FIGS. 1-2, including that of lugs 81a-81b axially movable in semi-circular slots 82a-82b, and of springs '32a-32b connecting the housings 52-53 to the inner supporting pipe 50. The spaced upper and lower packer members are identified at 35a and 35b. Other parts similar to those of FIGS. 1-2 have similar numerals with a or b designators.

The lower packer housings 54-55 are supported in spaced relationship to housings 52-53 by the threadedly connected mandrels or connector pipes 56 and 57. The upper ends of housings 54-55 are formed with chambers functioning as cylinders 58-59 and containing the sleevetype pistons 60-61, the latter being activated through channels 62-63 leading from cylinders 58-59 to the inner walls of housings 54-55, terminating opposite pipe 50.

The upper ends of pistons 60-61 are flanged to provide supports for the collapsible packer seats 40a-40b. The upper ends of packers 35a-35b are connected to upper housings 52-53 by vulcanization to threaded sup porting collars 33a-33b.

A main treating and testing port 65 is located in housing 54 with its inner terminus facing pipe at a point opposite the terminus of channel 62. Co-operating with these channels is a port 66 carried by pipe 50 and a sealing ring 67 in the wall of housing 54, disposed at an angle transversing that of ports 65, 66 and channel 62.

In lower housing 55, pipe 50 carries another port 68 opposite the terminus of channel 63, and sealing ring 67a is similarly located respecting these. Housing does not open externally, as does housing 54.

The general operation of the multi-packer type tool thus described is as follows: In the FIGS. 3-4 position the tool is in the collapsed, or lowering-in position with both packers 35a-35b and collars 40a-40b collapsed or lying fiat against the tool structure. By virtue of the stress exerted by springs 3211-3212, as controlled by lugs 81a81b moving in channels 8241-8212, both packer assemblies are in a position relative to pipe 50 where ports 66 and 68 are connected to channels 62-63 and cylinders 58-59.

When the tool is lowered to the selected bore hole position, pumping into pipe 50 from the surface will force fluid into the cylinders 58-59, causing pistons 60-61 to exert powerful compressive forces upwardly, in turn activating the collapsible seats 40a-40b, and packers 35a-35b into the positions shown in FIGS. 5 and 6. In this position, the packer assemblies are rendered immovable, and by clockwise rotation of the pipe 50, its port 66 is moved across sealing ring 67 into connection, with main port 65, channel 62 at the same time being sealed off with its fluid charge retained.

Simultaneously, the same rotation of pipe 50 will move port 68 across sealing ring 67a, leaving channel 63 and port 68 in sealed-off condition, as shown in FIGS. 5-6. In this position, the tool has sealed off the formation between packers 35a-35b, and a fluid-line connection has been formed to the formation through ports 65, 66 and pipe 50.

To deactivate the tool, pipe 50 is allowed to rotate back into the FIG. 3-4 position by influence of springs 3201-321), whereupon the port system relieves the fiuid pressure in the cylinders 58-59. Pistons 60-61 will then retract, packers 35a-35b and seats 4011-4011 will collapse.

The details of packer and collapsible seat construction will next be described in further detail. In FIGS. 7-8, are details showing these elements as enlarged and extracted from FIGS. 3 and 5, it being understood that the construction would be substantially similar for the packer tool of FIGS. 1 and 2.

In FIGS. 7-8, the flexible packer element 35a is shown to be of the multi-ply split-sleeve construction of my Patent 2,738,013. The plies of this packer are of a suitable rubber compound or rubber substitute and its construction is extremely rugged, especially where as preferred, the plies are reinforced by cord or by fabric layers.

Nevertheless, due to the extreme pressures which arise in the fluid column of a well, especially during treating or testing operations after setting of the packers, rupture or dislocation of the packer material would occur in the direction of thrust without special confining or seating means.

Such means, in the seat 40a illustrated, preferably consist in a series of seat links 70, having flat upper faces, peripherally hooked on their inner ends to a ring 71, slidably mounted around mandrel 56 (or member 21 FIGS. 1 and 2, as the case may be). The design of of these links is best seen in FIGS. 9-11. Links 70 are tapered as much as possible so as to provide the flat, relatively uninterrupted seat-top seen in FIG. 11, yet have sufiicient clearance to assume the fiat collapsed position of FIGS. 7 and 9. The length of each of links 70 is selected to conform to the diameter of the drill hole, so that in the open position they substantially abut or narrowly clear the well walls. This measurement can be determined in advance by calipering tests, where necessary. The hooked inner ends of links 70 forming the hooks which loosely grip ring 71, are designed to avoid any shearing action.

As seen in FIGS. 7-11, links 70 are tapered outwardly from ring 71 to provide added strength near their extremities where the most pressure will be exerted on them.

Adjacent the extremities of seat links 70, are formed bores to receive the looped ends of the supporting arms, or rods 72, the lower ends of which are looped around a lower supporting ring 73. These loop connections likewise avoid any shearing action.

Ring 73 (as ring 71) is slidably mounted around mandrel 56, and the lower loops of rods 72 rest on the piston 60 (or member 23, FIGS. 1-2). A washer 74 (FIGS. 7-8) is provided to separate seat links 70 from the end of packer 35a and form a fiat surface to shield the movement of links 70 when activated.

The arms 72 are preferably at least twice the length of seat links 70 so that the thrust exerted on arms 72 is substantially longitudinal.

To prevent the joints formed by links 70 and arms 72 from collapsing inwardly when in the FIG. 7 or FIG. 9 position, a stop-sleeve 75 is provided to prevent these joints from moving inwardly past 180. Preferably this sleeve 75 is formed of soft rubber or the like which, while incapable of activating the packer seat 40a has suificient expansion characteristics to fill the interior void formed when the seat is activated, as shown in FIGS. 8 and 10, to prevent ingress of material which might otherwise jam the seat in open position.

From the foregoing, it will be realized that a packer is provided with confining means which will positively open to provide a seat substantially disposed on a plane at right angles to the escape forces exerted on the packer.

Under certain conditions, it may be desirable to similarly confine the upper ends of the packers by seat means of the type described. To substitute collapsible seats such as 40a, for collars 33a would require simple modifications of structure obvious in nature.

What is claimed is:

1. In a well packer, a body member, suspending means for lowering said body member in a well, a compressible resilient packer member carried by said body member, means for forcing said packer member into sealing contact with the walls of the well, and means confining at least one end section of said packer member against rupture or dislocation, said confining means consisting of a collapsible seat disposed around said body member adjacent said end section of said packer member, said seat being composed of a plurality of seat links peripherally pivoted around said body member, said links being of a length selected to conform to the diameter of the well bore when said links are opened to a position substantially at right angles to the body member, each of said links having a pivoted supporting arm extending away from the packer member, the extended ends of said supporting arms being pivotally connected to said means for forcing said packer member into sealing contact with the walls of the well.

2. A well packer according to claim 1, wherein the seat links have flat supporting faces confining the packer, said supporting faces increasing in width in the direction of the outer extremities of said links.

3. A well packer according to claim I, the space around said body member disposed inwardly of said seat links and said supporting arms containing means preventing the locking of the joints formed between said links and said arms.

4. A well packer according to claim 1, the space around said body member disposed inwardly of said seat links and said supporting arms being substantially filled with an elastic substance preventing the locking of the joints formed between said seat links and said supporting arms and expanding into said space as it enlarges upon actuation of said seat.

5. In a well packer, a body member, suspending means for lowering said body member in a well, a compressible resilient packer member carried by said body member, means for forcing said packer member into sealing contact with the walls of the well, means confining at least one end section of said packer member against rupture or dislocation, said confining means consisting of a collapsible seat disposed around said body member adjacent said end section of said packer member, said seat being composed of a plurality of seat links, the inner walls of which are pivotally looped around a supporting ring, said ring being slidably disposed around said body member, said links being of a length selected to conform to the diameter of the Well bore when said links are opened to a position substantially at right angles to said body member, each of said links near its extremity containing a hole forming a pivot connection connecting to an elongated supporting arm, said arm extending away from said packer member, the extended ends of said supporting arms being pivotally looped to a second ring slidably enclosing said body member, said second ring being sup ported by said means for forcing said packer member into sealing contact with the walls of the Well.

References Cited in the file of this patent UNITED STATES PATENTS 1,549,168 Townsend Aug. 11, 1925 2,229,325 Greene Jan. 21, 1941 2,490,350 Grable Dec. 6, 1949 2,738,016 Lynes Mar. 13. 1958

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