RU2015346C1 - Device for sealing injection wells - Google Patents

Abstract

FIELD: sealing of injection wells. SUBSTANCE: device has flexible expanding hose with heavy-duty frame connected with valve for preliminary outward thrust of device in well. End face valve is in form of removable body with holes in end face and side walls and has flexible collar for preliminary building up of fluid pressure for producing outward thrust of hose. Collar is installed above holes on stop protrusions of valve inner wall square to longitudinal axis of device. EFFECT: higher efficiency. 5 cl, 4 dwg

Description

 The invention relates to mining and can be used for hydroprocessing of outburst coal seams and as a means to carry out blowout control measures.

 A device for sealing wells, including a water seal and a spring-loaded valve [1].

 However, this device does not provide the necessary reliability of the injection wells.

 Closest to the proposed is a sealing device, consisting of an elastically expanding sleeve, collapsible end equipment for connecting the sealant to the pipeline and a mechanical valve for preliminary expansion of the sealing device in the injection well [2].

 However, this device is not sufficiently reliable. When the fluid is injected into the well, the elastically expanding sleeve expands, this leads to the appearance of large stresses in the force frame of the elastic expanding sleeve, as a result of which its integrity is violated. In addition, the mechanical spring-loaded valve often fails, which also causes additional problems during operation of the device.

 The aim of the invention is to increase the reliability of the design of the device and reduce the complexity of its use.

 This goal is achieved by the fact that in the known device, including an elastically expanding sleeve, a collapsible end apparatus and an end valve, the elastically expanding sleeve inside has a longitudinal channel that covers at least two layers of the power frame located in the rubber-plastic body of the sleeve. The end valve is made in the form of a closed removable hollow body of a perforated hole with an elastic cuff to create a preliminary pressure of the expansion fluid in the device for expanding (wedging) the sleeve in the well, the elastic cuff being installed in the valve normally to the direction of flow of the injection fluid and a throttling hole is provided for filling well cavity fluid. The cuff is made in the form of a cork wrapped on circular protrusions provided on the inner side of the walls of the body of the hollow body of the mechanical valve.

 To increase the reliability of the operation of the device, the power cage is equipped in an elastically expanding sleeve with a preliminary stress, for which it is stretched in diameter before compressing it into the vulcanizing sleeve and, accordingly, compressed in length by up to 0.1 of its original length. When injecting liquid and spreading the device in the well, this somewhat reduces stresses in the power frame and the sleeve body near the frame.

 To increase the efficiency of the mechanical valve in the device design, the elastic cuff-plug and circular protrusions perform the possibility of slipping (one-time opening) of the cuff-plug only when the pressure of the injected fluid reaches the set value, and this value is at least 2 MPa ( 20 atm).

 To fill the bottom of the well with liquid before the valve is actuated, a hole is made in the center of the cuff longitudinally along the device axis. The latter is provided, since when the valve is triggered, a sharp exit of fluid from the sealant to the bottomhole of the well may occur, while the pressure of the spacer decreases and the sealant will be ejected from the bottom of the well.

 The cuff can be made in the form of a washer made of elastic material with the hole dimensions of this washer corresponding to the calculated dimensions of the blowout longitudinal hole, and it is provided that when the device is triggered, the disposable washer is chipped off (cut off) on the thrust ledges. In addition, for the possibility of reusing the washer cuff, the thrust ledges in the valve are made in the form of pylons of at least three.

 The set of features contained in the application by the author was not found in the studied scientific, technical and patent literature. Therefore, the proposed set of features has novelty.

 The use of the features noted in the application can significantly increase the efficiency of the device when injecting fluid into the formation using wells due to the formation of a special design of the end valve in the form of a cuff in the end of the hydraulic lock, and this cuff is made in the form of a cork.

 As for the characteristics given in the following claims, they are aimed at the fact that the injection of fluid into the reservoir using the proposed device was carried out more efficiently and effectively.

 In FIG. 1 presents the proposed device; in FIG. 2 - end part of the valve; in FIG. 3 is a section AA in FIG. 2 (a persistent ledge in the valve is made in the form of a solid oval); in FIG. 4 is a section AA in FIG. 2 (the stop ledge in the valve is made in the form of pylons).

 The device consists of an elastically expanding sleeve 1 connected via a fastening sleeve 2 to the mechanical valve 3 for preliminary expansion of the device in the well. The valve 3 consists of a housing 4, into which a cap 5 is screwed. End caps 6 are made in the cap 5, and side openings 7 are provided in the casing 4 for providing fluid to the well. In the inner part of the valve body 4, thrust ledges 8 are made in the form of an oval, a cuff 9 is installed on them, made in the form of a cork with a blowout hole 10 longitudinal along the axis of the device. Valve body 3 on the side opposite to the holes is made with a threaded part 11, which, when the assembly of the device is screwed into the threaded part 12 of the fastener 2. The elastic expansion sleeve 1, when assembling the device after special cutting, is secured to the nipple fastener 2 using special clamps 13. The elastic expander Av 1 consists of outer 14 and inner 15 parts of a rubber pipe, between which there is a power, for example, metal, frame 16, consisting of several layers of braid with rubber interlayers, and a channel 17 for supplying liquid is provided inside the sleeve 1.

 The technical solution provides a second embodiment of the mechanical valve 18, in which the thrust ledges 8 are made in the form of ovals 19 (see Fig. 3) or in the form of pylons (see Fig. 4). The cuff 9 is made in the form of a washer-membrane 20 with an anti-blowout hole 21 of the same size.

 The device operates as follows.

 A pre-assembled device is installed in a well drilled to pump fluid into the formation. A pipeline is laid and a pump is connected to it, then the pipeline is connected using a collapsible end equipment to a sealing device installed in the well. The pump is turned on and the fluid injected into the reservoir enters the channel 17, then the fluid enters the valve body 4. The fluid pressure in the device gradually increases, while part of the fluid enters through the longitudinal hole 10 in the cuff 9, and then through openings 6 and 7 in the body - into the well. The well is filled, and the pressure in the device rises and the gradually expanding sleeve expands and wedges in the well. When filling the well with liquid, which is evident at the beginning of its flow out of the well, the pump is turned on at full power. The pressure in the well reaches the valve response pressure, usually of the order of 2 MPa (20 atm). The valve operates as follows: the cuff-cuff 9 slides under pressure ledges 8 under fluid pressure, remaining in the housing cover. Fluid flows freely into the array and fluid is injected into the formation. In subsequent cycles of use of the device, the tube-cuff 9 is again installed on the thrust ledges 8.

 In the case of using a mechanical valve using washers as a membrane (see Fig. 2-4), the following occurs. The washer-membrane 20 under the pressure of the liquid is chipped on thrust ledges in the form of ovals 19.

 The use of this device in coal mines during injection of fluid into the reservoir can significantly increase the efficiency of fluid injection and reduce the complexity.

Claims (5)

 1. DEVICE FOR SEALING EXPRESSION WELLS, including an expanding sleeve with a power frame, connected by a fastener to the end valve for preliminary expansion of the device in the well and connected with it and connected to a collapsible end equipment for connecting the sleeve to a high-pressure pipe, characterized in that In order to increase the reliability of the device and reduce the complexity of its use, the power frame is located in the sleeve and is made of at least two layers, and the end valve is made in the form of a removable hollow body with holes in the end face and side walls for supplying fluid to the well and with an elastic cuff to create a preliminary pressure of the sleeve expansion fluid in the well, the elastic cuff being installed above the holes perpendicular to the axis of the device, made in the form of a tube with a longitudinal axis of the device an anti-blowout hole and is supported on thrust ledges made on the inner wall of the valve.  2. The device according to p. 1, characterized in that the cuff and the persistent ledges of the valve are made with the possibility of slipping the cuff through the ledges upon reaching the working pressure of the pumped fluid in the sleeve.  3. The device according to claim 1, characterized in that the cuff of the valve is made in the form of a washer of elastic material.  4. The device according to claim 1, characterized in that the cuff is made with the possibility of chipping or cutting it on the ledges upon reaching the working pressure of the injected fluid.  5. The device according to claims 1 and 4, characterized in that, in order to reuse the washer, the thrust ledges are made in the form of at least three pylons.

Images