US2378469A - Oil well apparatus - Google Patents

Description

June 19, 1945. 1.. E. DENTON OIL WELL APPARATUS Filed April 19, 1941 2 Sheets-Sheet l 4 LEWIS E DENTON v INVENTOR. JMmQQQMk.

June 19, DENTQN O IL WELL APPARATUS Filed April 19, 1941 2 Sheets-Sheet 2 LEWIS E. DENTON.

INVENTOR. Q mfi. (32am.

Patented June 19, 1945 UNITED STATES PATENT OFFICE' 011. WELL APPARATUS Lewis E. Denton, Houston, Tex.

Application April 19,1941, Serial No. 389,262

6 Claims.

the plug. In some instances it is desirable to leave this plug in position while in other situaons it is desirable to remove the plug.

Under some circumstances it is desirable to place a, packer in the well either above or below a level at which cement or acid pressure is applied to the well bore; or it is desirable to confine the pressure applied to the well bore either from above or below; or in some instances to segregate a section or elevation of the well between two retainers or plugs and apply cement or acid under pressure to the section so segregated.

The present apparatus contemplates a device or an assembly of devices by which the foregoing operations may be performed.

One object of the invention is to provide a removable tool which may be used as a cement retainer, a packer, a bridge plug, or a swab by making very slight variations in the assembly of the tool.

Another object of the invention is to provide a tool for wells wherein a packer may be expanded by the application of hydraulic pressure, and either retained in expanded position by the pressure or mechanically locked in such expanded position.

Another object of the invention is to provide a cement retainer wherein the initial pressure applied to the tool is utilized to set the packer and such pressure simultaneously opens the tool for theilow of material therethrough.

Another object of the invention is to provide an assembly which may be set as a bridge plug in the well bore by hydraulic pressure and circulation therethrough cut oil? by manipulation of the assembly from above.

Still another object of the invention is to provide an assembly for well bores wherein retainer or plug may be set below the formation to be treated or cemented and a retainer set I above the formation so that the hydraulic pres- I sure applied can be used for setting both the plug and the retainer and for applying pressure to the formation.

Still another object of the invention is to provide a removable packer or retainer or bridge plug which can be set and released by hydraulic pressure and which may be removed or left in the hole as circumstances require.

Other and further objects of the invention will be readily apparent when the following description is considered in connection with the accompanying drawings wherein:

Fig. 1 is a vertical sectional view illustrating the tool as it is about to be lowered into the well bore..

Fig. 2 is a vertical sectional view showing the tool in its final position in the well bore with the slips and packer expanded and set by means of hydraulic pressure.

l5 Figs. 3 and 4 are transversesections taken on the lines 3-3 and 4-4, respectively, of Fig. 1.

Fig. 5 is a vertical sectional view of the device of Fig. 2 where it has been converted into a. bridge plug and set in the well bore by means of hydraulic pressure.

Fig. 6 is a vertical section of a well bore wherein the combination tool has been utilized to oement a predetermined section of the bore and illustrating two of the tools connected in tandem to isolate such formation, the lower tool being left in the bore hole as a permanent bridge plug after the cementing operation.

. Fig. 7 is a side elevation of the upper end of the tool illustrating the passages as having been closed to cut off circulation through the tool from either direction.

Fig. 8 is asection taken on the line 8--8 of Fig. 7.

The tool is shown in its normal unexpanded position in Fig. 1 wherein the operating pipe 2 is connected to a coupling 3 which is in turn provided with a coarse left hand thread 4 by which it is connected to a head 5.

The head 5 has an opening 6 therein leading into a back pressure valve chamber 1. Leading from the base of this chamber are a plurality of vertical openings 8 by which the flow of fluid may pass through the device.

This head 5 is connected to the upper end of the body In by being threaded at H thereto. It is intended that this thread I I may be subjected to turning for a purpose hereinafter to be described.

The upper end of the body l0 may be of a solid construction, or if the body I0 is formed of a pipe the upper end will be closed by theplug H which serves as a support for the back pressure valve 13 normally urged against the seat It by means of the spring I5. This valve closes the 55 head 5 against any upward flow.

Pcsitimed directly below the head 5 and also hi-'adcd on to the upper body I0, is a cylinder 20. .This cylinder has an enlarged chamber 2| therein which extends throughout a greater portion o its length. Leading into this chamber are the passages 22 which are arranged for alignment with the passages 8. as best seen in Fig. 3, which is a section looking down on the base of the chamber I and into the passages 8.

The cylinder is arranged to receive the piston which is slidably mounted upon the body or pipe In. The upper end of this piston is disposed in the chamber 2| in the cylinder so that any fluid pressure applied through the pipe 2, the openings 8 and 22 will be exerted on this piston, tending to move the piston downwardly. A

small leak or vent 26 is provided in the body In adjacent the upper end of the chamber 2| so as to allow the free working of the piston, but the volume of fluid which may escape through this vent is immaterial. The vent 26 is provided to insure the passage of any pressure below the tool into the chamber 2| after the device has been left in the bore hole as a bridge plug and the possages 8 and 22 are turned out of alignment. This pressure from below would then be applied as a force on the top of piston 25 and set the slips tighter.

The piston 25 has a flange 28 thereon which is arranged to confine the upper end of a resilient packing 29 and has an inner skirt portion 30 which serves as a packer barrel and extends downwardly into the recesses 3| in the base 32. The base 32 is also slidably mounted on the body I and is normally supported by a set of slips 33 which are urged inwardly by the spring arm supports 34 anchored to the nipple 35 which is amxed to the lower end of the body It.

From the foregoing construction it seems obvious that when a pressure is applied through the operating pipe that it will cause opening of the back pressure valve l3, as best seen in Fig. 2, so that the flow will pass through the chamber 1, the passages 8 and 22, and enter the chamber 2|. In this manner a pressure will be exerted on the piston 25, causing it to move down, as seen in Fig. 2, to thus expand the packing in a radial direction to form a seal with the wall of the well bore or with a pipe or casing 31.

The piston, of course, moves downwardly, forcing the packing and the base 32 ahead of it and the tapered face 38 on the base causes the outward movement of the slips to grip the pipe 31 or the face of the formation. When the slips can not be forced outwardly any further the continued movement of the piston applies pressure to the packing to cause its expansion.

Fig. 2 shows the body l0 as having a slot or opening 40 therein which is spaced at such an elevation that it will be uncovered by the piston 25 by the time that the packing is expanded. In this manner the body l0 will be open so that a flow of fluid may occur downwardly through the tool to an elevation below the tool by passing through the central opening 4| in the body.

With the construction just described the device may be used as a removable packer through which a circulation may be had; it may be used as a removable cement retainer which will be set by the hydraulic pressure and still allow the flow of cement therethrough. On the other hand, it may be used as a well or bridge plug after cementing operations by pumping the cement therethrough and turning the pipe 2 to the right with the weight of the pipe 2 resting on the tool,

this manipulation causing the small angular movement in the connection 44, thus causing passages 8 and 22 to become misaligned and cutting off circulation through the tool.

The back pressure valve may be used to trap the applied pressure because it is normally urged to closed position and will trap any pressure which has been forced through .the tool. If, when used as a packer or retainer, it is to be left in the well bore, it is only necessary to unscrew the lefthand thread at 4 to remove the operating pipe. 0n the other hand, if it is desired to posi- 'tively close the tool and in this manner shut off any return flow of the fluid or pressure from the well, the construction best seen in Fig. 7 may be utilized.

Due to the arrangement of the connection at 44 between the head 5 and the cylinder 20, it is possible by turning the operating pipe, to turn the head and Fig. 7 shows the head as having been turned a portion of a revolution so as to move the openings 8 out of alignment with the openings 22. In this manner the flow in either direction is cut off and the tool is positively closed. Fig. 7 has omitted the back pressure valve. s

Fig. 5 shows a slightly modified form of the device which is substantially identical with that of Fig. 1 except that an annular recess has been provided on the inner face of the cylinder 20, and this recess carries a spring lock ring 5|. This ring is arranged to snap into the recesses 52 in the periphery of the piston, each recess having an inclined upper shoulder 53 which forms a ratchet connection so that the piston may move downwardly but will be latched by each tooth in turn to prevent'its return movement. In this manner the slips 33 and packer 29 can be positively locked against release.

Fig. 5 shows a lower locking ring 55 which may be applied in lieu of the ring 5| or it may be used in combination with it. This ring 55 looks the piston with the packing in expanded position and the device may be thus used as a swab if desired, in which case the slips.would be omitted. This ring 55 may be omitted when the ring 5| is used or it may be used as a double look when the piston moves to its extreme downward position.

It is to be understood that the device described may be used as a packer, a removable cement retainer, a bridge plug, or a swab, and that by slight variation such as the'removal of the back pressure valve, the insertion or the removal of the locking rings and the use of the body Ill either having or omitting the port 40, enables one to use the tool for various purposes.

It should be noted that the body ill in Fig. 5 has omitted the port 40 and that there is no passage whatsoever through the tool, no passage through the tool being necessary if it is to be used only as a bridge plug. 7

In this form the tool could be used as a bridge or plug which could be set and locked permanently to remain in the well bore. However, a threaded section 12 is provided on upper portion of head 5 making it possible to connect to the bridge plug with a. fishing tool and pull the plug by means of lift from above. This would involve shearing of locking ring 5| from its recess. This would eliminate the drilling out of the plug should itbe desirable to remove it.

Fig. 6 shows two of the tools arranged in combination together with the lower tool 60 carried by an intermediate section 6| of the operating pipe, with the upper tool 62 connected directly to the operating pipe 2. With this construction the assembly may be lowered into the well to a desired elevation either inside of the casing, such as 6|, or in an open hole. In Fig. 6 the casing 64 has been perforated at 65 and it is desired to cement or otherwise block oil a formation such as 66. With this construction the pressure is first applied and the upper tool 62 is set in position by expanding the packing 29 and the slips 33. This anchors the tool firmly in position and it is of the type shown in Fig. 2 which would serve as a removable cement retainer. When the upper tool 62 has been set by hydraulic pressure the port 40 in tool 62 will have been opened by downward movement of the piston 25. This will permit passage of the fluid through tool 62 and into pipe 6|. A portion of this fluid will flow through the percement, and a releasable connection of said pipe with said bridge plug so that said retainer may bore outside of said pipe, a series of perforations forations in pipe 6| and a portion of the fluid will flow into the top of lower tool 60. Since force from a liquid under pressure is transmitted equally in all directions, the hydraulic pressure in the lower tool 60 will cause lower tool 60 to be set in same manner as upper tool 62.

The upper tool 62 may be in the form of the retainer type such as shown in Fig. 2, either with or without the back pressure valve, the object being to pump a body of material therethrough and to thereafter be able to either remove the upper tool 62, leave the lower tool 60 in place, or in some instances to remove both tools. The tools thus used could be either removed or left in the bore hole, depending on the operation desired and whether or not locking ring 51 is used.

Fig. 6 shows a seal ring 10 arranged about the pipe 8| below the tool 62. This is an expansible type packing having a lip portion H which is intended to expand by the application of pressure from below. This seal ring is intended to exclude cement or other material from the slips 33 on the bottom of the tool 62. This merely facilitates the removal of the tool. 7

If it is desired to insure that the tool will remain inoperative until it reaches the desired elevation the ring 5| may be made of such strength that it will only permit sliding of the piston when a pressure above that of the hydrostatic pressure in the pipe is exceeded or other suitable means may be provided such as shear pins, a frangible plate in the pipe or the tool might be arranged so that the passages 22 would be closed as in Fig. 7.

Broadly, the invention contemplates a tool which may be used as a cement retainer, packer, bridge plug, or swab which may be either permanently or temporarily anchored in position and wherein'a plurality of the tools may be used in combination together, each tool being set by the application of the hydraulic pressure which is to 'be used in performing the operation in the well.

What is claimed is:

1. A combination bridge plug and cement rein the pipe to discharge cement into the bore above the plug, a cement retainer assembly in the 'pipe above the perforations, a packer thereon to be set by the fluid pressure in the pipe, means to temporarily close said retainer after the application of the cement so as tov hold pressure on the cement, a releasable connection of said pipe with said bridge plug so that said cement retainer may be removed, and means to exclude the cement tainer assembly for wells where the well is to be plugged and cemented at an elevation above the bottom including an operation pipe, a bridge plug having a packer thereon closing the lower end of said pipe, means in said plug to set said packer by the application of hydraulic pressure tothe packer so as to anchor the plug to close the well bore outside of said pipe, a series of perforations in the pipe to discharge cement into the bore above the plug, a cement retainer assembly in the pipe above the perforations, a packer thereon to be set by the fluid pressure in the pipe, means to close said retainer after the application of the from the bottom of the retainer.

3. A tool to be used in a well to either temporarily or permanently close the well bore compris-.

ing an operating pipe, a hollow head thereon, a

body connected to said head, a cylinder connected to and surrounding said body below the head, openings in said head and cylinder which are adapted to provide communication between the interior of the head and the cylinder when the head and cylinder are moved to align such openings, a piston slidable on said body and within said cylinder, a skirt on said piston, a packing about said skirt, a packer base slidable on -said body and supporting said packing, a tapered surface on said base, slips on said body and engageable with said tapered surface of said base so that liquid under pressure applied through said pipe will pass through said openings into said cylinder to move said piston to compress the packing which in turn forces said base against the slips, said head and cylinder being relatively rotatable to move the openings out of alignment.

4. In a retainer or bridge plug for wells the combination of, a body, a piston slidable thereon, a base slidable on the piston, a cylinder secured to said body and extending about said piston, a packer on said piston to be expanded between said piston and said base by fluid pressure in said cylinder acting on said piston to efiect movement thereof, said cylinder comprising relatively movable portions having openings in each portion, said portions being movable so as to move the openings in one portion from alignment with the openings in the other portions to cut oil the fluid pressure through the cylinder to the piston.

5. A cement retainer or bridge plug for wells comprising a tubular body having a passage therethrough including a lateral opening, a tubular cylinder exteriorly of the body and arranged to communicate with the lateral opening in the body, a piston slidable on the body and having a portion thereof extending into said cylinder and closing said lateral opening when in one position, a base portion supported on said body and slidably surrounding said piston, a packer disposed on said piston between a shoulder thereon and said base and normally supporting said piston in a position closing the opening in the body when the packer is unexpanded, whereby liquid'under pressure applied to said body efiects movement of said piston to uncover said opening for the flow of the liquid through the body, and expands said packer.

6. A cement retainer or bridge plug for wells comprising a tubular body having a passage therethrough including a lateral opening, a tubular cylinder exteriorly of the body andarranged to communicate with said lateral opening, a piston slidable 0n the body and having a portion thereof extending into said cylinder and closing said lateral opening when in one position, a base portion slidably supported on said body and surrounding said piston, a packer disposed on said piston be- 10

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