SU1452933A1 - Arrangement for producing dividing bridge in wells - Google Patents

Abstract

The invention relates to the drilling of wells. The goal is to increase the carrying and sealing ability of the bridge by uniformly filling the space around the hollow body with combustion products. For this purpose, a spring element 7 with a fusible stopper 8 is placed on the support assembly 4 with grooves 5 and side holes, and in the assembly, at the level of the openings 6, an external annular groove is made to exit the combustion products,

Description

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I The invention relates to the drilling of wells, in particular, to devices for creating uncoupling bridges in casing.

 The purpose of the invention is to increase the carrying capacity and sealing ability of the bridge by uniformly filling the space around the hollow body of the device with combustion products.

: FIG. 1 shows the device section; in fig. 2 - the same kind of assembly.

A device for creating a disconnecting bridge in wells, which is lowered onto a cable-rope, consists of a hollow body 1, inside of which is placed; combustible material 2 (termite composition) with igniter 3, support unit 4 in the lower part with grooves 5 and side openings 6 for exit of combustion products. In the support unit 4 in the outer annular groove, made at the level of the holes 6, a spring element (spiral) 7 made of an elastic metal (for example, spring wire) is located. The coil 7 is kept from unwinding by a low-melting gate 8 installed in the side openings 6 to exit the combustion products. Under the spring element 7, at the level of the annular groove, additional side openings 9 are made to exit the products of the hearth, in which a low-melting gate can also be installed. In the support unit 4, a cavity 10 is made under the annular groove, connected to the cavity of the housing 1 under the combustible material 2.

A differential piston 11 with rubber seals 12 and a groove 13 is fixed in the cavity of the housing 1 above the combustible material 2. A piston 14 is located above the piston 11, fixed to the housing 1 by shear elements 15 and forming a piston cavity 16 with the piston 11, in which the diaphragm 17 and charge

18, An annular groove is made on the inner surface of the cover 14.

19, in the case opposite the groove there is an upper row of radial holes in which the balls are placed

20, extending into the annular groove 19, below is a series of holes with balls 21, which extend into the groove 13.

In the lower part of the housing, the cavity 10 is connected to the space filled with combustible material 2 by means of an aperture covered by a diaphragm 22 with a rubber stopper 23.

The device works as follows.

After the device is lowered into the well, when the first electrical impulse is supplied, the igniter 3 is triggered, which ignites the thermite composition 2, the molten pure iron with a temperature of 2000-2400 ° C, formed during the combustion of the thermite composition, separates from the slag that floats above it. From the second current pulse of the other polarity, the charge 18 is activated in the piston cavity 16. The elements 15 are cut off from the effects of the explosion products, the cover 14 is moved upwards and releases the balls 21 from the stopper. The piston 11, which is under the influence of hydrostatic pressure, begins to move into (-; and: and pushes the balls 21 out of the oTBepcTirii into the well.

Moving downward, the piston 11 displaces pure iron, which melts the diaphragm 22, and then releases the low-melting gate 8, which holds the helix 7 in a compressed state. The coil 7 is then released and deployed, closing the gap between the support assembly 4 and the walls of the casing and simultaneously fentures the device in the casing. The piston 11 simultaneously continues to force clean iron into the well through the holes 6 and through the holes 9 under the untwisted spiral 7. The removed iron through the holes 6 rises along the gap between the device body and the pipe. The helix 7 retains the displaced iron and allows it to be evenly distributed throughout the gap. At the same time, the helix 7 is partially melted in the iron, which, upon solidification, creates a stronger weld. Contact with the casing walls of the column provides a quick process for cooling and solidifying iron. The body 1 is welded with helix 7 and together with the casing.

The piston stroke is designed so that it displaces only pure iron, and the slag remains in the sub-piston chamber. At the end of the downward movement of the piston, its upper end faces below the holes with the balls 20, as a result of which the cap 14 is released from the housing and when the cable is tensioned, the cable is removed. from the well. An isolation bridge is installed in the well.

After detonation of charge 18 in the case of non-ignition of the thermite composition, the latter prevents the piston from moving downwards and, thus, disengaging the grip from the device. The device is then removed to the surface.

To prevent the inner surface of the housing 1 from melting

the gap between the thermite composition and the corus, as well as the cavity 10 and the holes 6 and 9 can be filled with a refractory lining (for example, magnesite),

Claims (2)

Invention Formula 1, A device for creating a disconnecting bridge in wells, running through a cable-rope, including a hollow body with combustible material and an igniter, the supporting unit in the lower part with grooves and side openings for the exit of combustion products, a differential piston fixed in the housing cavity above the combustible material, a clamp above the differential piston connected to the hollow housing with a shear element, and a piston cavity below the die with a charge that differs with that to increase the bearing and sealing capacity of the bridge by uniformly filling the space around the hollow body with combustion products, it is provided with The support unit has a spring element with a low-melting gate, an external annular groove is made in the support node at the level of the side openings for the exit of the combustion products, and under it is a cavity connected to the body cavity under the combustible material, while the spring element is installed in the ring groove and the low-melting gate - in side holes for the exit of combustion products, 2. The pop-up device, 1, differs from (the fact that in the support unit under the spring element at the level of the outer annular groove there are additional side openings for the exit of combustion products. Thebes. 2 7 IM- iz