SU1562434A1 - Method of isolating a formation - Google Patents

Abstract

The invention relates to the development of oil and gas fields. The purpose of the invention is to increase the efficiency of the process. Install the sealing element and the secondary winding of the transformer on the outer side of the casing. The control unit with the primary winding of a transformer connector with a core of soft magnetic material is lowered into the well into the interval of installation of the hermetic element. In this case, the transformer connector is made coaxial with the orientation of the windings coaxially with the casing. Initiation is carried out by applying a supply voltage that ensures the fulfillment of the conditions: B _core * 98B _{Art. k} and B _obm * 98B _{st. k} , where B is the _heart , B _{st. k} , B _obm are the magnetic induction values in the saturation mode of the core, wall of the column and winding, respectively. When these conditions are met, a guaranteed initiation of ignition of the powder charge of the hermetic element occurs. 1 il.

Description

This invention relates to methods for isolating a formation in the development of oil and gas fields.

The purpose of the invention is to increase the efficiency of the process.

The drawing shows the equipment for implementing the method.

The isolation equipment comprises a packer 1 (e.g., explosive) and a packer opening control assembly 2. Packer 1 is lowered into the well in the composition of the string of pipes 3 prepared for securing the well. The packer contains a sleeve 4 casing, made of magnetic material, hermetic metal sheath

5, the diameter of which in the initial position ensures the free passage of the pack into the well. Inside the shell 5, an explosive charge 6 and an electric detonator with filament 7 are provided, which is connected to the secondary winding 8 located around the sleeve 4 on its outer side. The winding 8 is part of a split transformer — the secondary winding. To prevent penetration of the well fluid into the cavity between the sleeve and the shell, seals 9 are provided. The packer control unit includes a housing 10 of non-magnetic or magnetic material, the primary winding 11 of detachable

O1

OE

Yu

4 Ј0 ъ

transformer, core 12 of magnetic material, which are components of the other half of the lift transformer with channels

13, in which seals are installed

14. The primary winding 11 is connected to a logging cable, on which the control unit is lowered into a well and a gin.

The method is implemented as follows.

A casing with packers is lowered into a well prepared for fastening. - The number of lowered packers and the place of their installation is determined depending on the requirements of the geological and technical conditions for isolating formations. After carrying out the necessary technological operations, for example, pumping cement mortar in the inlet and installing a cementing plug on the stop ring before the cement mortar hardens, the control unit 2 is lowered into the pipe string on the logging cable 15 to the location of the first one below the packer 1, the installation location is determined by measuring the cable, by magnetic marks or by means of a coupling locator, which makes it possible to mark the position of the joints 16 between column 3 and coupling 4 and calculate the location of the winding 8. After aligning the winding 8 and 119 that may establish and continuously moving unit 2 when applying a control current via a cable supplied voltage to the primary winding of the transformer 11 detachably. The magnetic lines of force of the primary winding 11 intersect the turns of the secondary winding 8 and a current arises in the circuit of the electric detonator 7, which causes the burning of the explosive charge 6.

Under the action of the resulting high pressure, the hermetic packer shell 5 opens or expands to the borehole wall, isolating the underlying horizons from the overlying ones. Then the packer opening control unit is raised to the location of another packer and the well is sealed in another interval, etc. After the completion of the well seal, the control unit 2 is lifted to the surface. To ensure maximum efficiency of the proposed equipment, you must select core materials 12 and the walls of the coupling 4 so that

0

sulfur up to;

where in,

 se pЈ.

AT

Art. to

AT

0 & / l

,

magnetic induction value of the core in saturation mode, T; the value of the magnetic induction of the wall of the column in the saturation mode, T; the value of the magnetic induction of the winding 9 in the saturation mode, T.

The use of coaxially made windings in the proposed equipment allows to significantly simplify its manufacture, and the new design becomes more technological, its reliability and productivity increase.

Claims (1)

25 claims A method of isolating the formation, which involves installing a secondary winding of a transformer connector equipped with an explosive charge filament inside a hollow sealed equipment 0 five five 0 The cords placed outside the casing, and the descent into the primary column of the transformer connector, followed by initiation of electrical current flow in the secondary circuit of the transformer connector, characterized in that, in order to increase the efficiency of the process, the windings of the transformer connector are set coaxial to the axis of the casing, and the initiation of the flow of electric current in the secondary circuit is carried out while ensuring that the condition   st to Bye "m lo.", magnetic induction value of the core in saturation mode, T; the magnetic induction value of the casing wall in T saturation mode; the value of the magnetic induction winding in saturation mode, T. where in with “P9” 9 ST.ts AT smf Compiled by A.Sokolov, Editor O.Golovach Tehred L.Oliynyk Order 1041 Circulation 478 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 Production and Publishing Combine Patent, Uzhgorod, st. Gagarin, 101 Corrector t. Paly Subscription