RU2318982C1 - All-purpose impulse electrohydraulic percussion means for well treatment - Google Patents

Abstract

FIELD: oil production, particularly equipment for hydroimpulsive reservoir treatment for reservoir productivity increase, for fresh and mineral water production, for well cleaning of foreign articles.

SUBSTANCE: device comprises body made as shell with cylindrical walls and bottom. Working chambers are formed as two side cells made in side outer walls of the shell and symmetrically arranged from both sides thereof, and as one central cell located in central part of outer bottom surface. Electrode pairs are installed in the cells. The electrodes are spaced one from another and linked to lower high-voltage cable ends. Driving unit is made as high-voltage pulse source provided with switchboard for selectively high-voltage pulse supply. Upper high-voltage cable ends are linked to the switchboard. Cell made in shell bottom surface is communicated with ones made in side walls via through channels for free fluid flow.

EFFECT: simplified structure, extended usage range, increased force to be applied to well wall and improved operational reliability.

2 cl, 3 dwg

Description

The invention relates to techniques for hydroimpulse effects on reservoirs in wells, used to increase reservoir productivity in the oil and gas industry, in the development of fresh and mineral waters and can be used, in particular, when cleaning wells from objects stuck in them.

Known pulsed hydraulic hammer for wells, designed to impact by hydraulic shocks on the walls of the wells and containing a housing, working chambers filled with liquid, in which the windows are made, and the drive unit. See, for example, RF patent No. 2184207 IPC Е21В 28/00 "Downhole pulse source for impact on the walls of the wells", publ. 06/27/2002, in B.I. Number 18.

The hydraulic pressure in it is due to the use of ball shutter devices, which, according to the operator’s signals, act on the gas available in the working chambers. As a result of the interaction of the gas with the surrounding fluid, a shock hydraulic wave arises on the walls of the well.

A disadvantage of the known impulse impactor is that for repeated exposure to the walls of the well, it must be lifted and recharged with gas. In addition, it has a complex structure and is not reliable in operation.

The closest and adopted as a prototype is a pulsed hydraulic hammer for impact on the walls of the well, comprising a housing, working chambers filled with liquid, in which the windows are made, and a drive unit. See, for example, RF patent No. 2151265, IPC E21B 28/00 “Device for creating hydraulic pressure pulses in a well”, publ. 06/20/2000 in B.I.

The operation of the device occurs due to the supply of working fluid from the surface, the flow of which is interrupted by a special valve.

A disadvantage of the known pulsed hydraulic hammer is that for its operation it is necessary to supply the working fluid from the surface. In addition, the device itself is quite difficult to manufacture and develops relatively small pressures. And thanks to the large number of parts rubbing together, it is not reliable in operation.

The objective of the invention is to simplify the design, expand the range of applications, increase the force acting on the walls of the wells and increase the reliability.

This problem is solved due to the fact that in a universal pulsed electro-hydraulic hammer for wells containing a housing, working chambers filled with liquid, in which windows and a drive unit are made, according to the invention, the housing is made in the form of a sleeve with cylindrical walls and a bottom, the working chambers are holes, two of which are made symmetrically on both sides in the outer walls of the liner, and the third hole, made in the Central part of the outer surface of the bottom, pairs of electrodes are installed in the holes, section lennye gap and connected to the lower ends of the high-voltage cable and the drive unit is a source of high voltage pulses to the switch that provides the sequence of supplying high voltage pulses to which are connected the upper ends of the high-voltage cable.

In a variant of the technical solution, the hole on the outer surface of the bottom is connected to the holes made in the outer walls of the sleeve through channels for free flow of fluid.

Universal pulsed electro-hydraulic hammer for wells is illustrated in Fig.1-3.

Figure 1 shows a hammer in longitudinal section.

Figure 2 shows a schematic diagram of a control panel.

Figure 3 presents a schematic diagram of the inclusion of pairs of electrodes.

Universal pulsed electro-hydraulic hammer for wells is arranged as follows. The body of the hammer is made in the form of a sleeve with thick cylindrical walls 1 (Fig. 1) and a massive bottom 2. The upper part of the body is equipped with an external thread 3 for connection with a pipe string (not shown). Two working chambers 4, 5, which are spherical dimples, are made outside the walls of the sleeve. Wells 4 and 5 are located symmetrically on both sides. In the central part of the outer surface of the bottom 2, a third spherical hole 6 is made. The outer surface of all holes has an insulating layer of 7, 8, and 9, respectively, made of cermet or an elastomeric material, for example, polyurethane or rubber.

In a variant of the technical solution, the bottom hole 6 is connected to the side holes 4 and 5 through channels 10 and 11 for free flow of fluid.

A pair of electrodes 12, 13 and 14, respectively, are installed in the wells, which are thick steel pins separated by gaps (not marked). The electrodes are connected to the lower ends of the high voltage cable 15, while one of the electrodes of each pair can be connected to the same core multicore cable. The upper ends of the high-voltage cable 15 are connected to a source of high-voltage pulses 16 (Fig.2, 3), which acts as a drive unit. The source of high-voltage pulses 16 is connected to an external source of alternating current and contains a switch (not indicated), which ensures the sequence of supply of high-voltage pulses. When you select a pair of electrodes that should receive a high voltage pulse (s), the switch has buttons 17, 18, 19 and 20. When you turn on the buttons 17-19, the corresponding switching elements 21, 22 and 23 are turned on, preparing the selected pair of electrodes for feeding high voltage. When the button 20 is pressed, the power contact 24 is connected, connecting the electrodes to the high-voltage pulse generator.

Universal pulse electro-hydraulic hammer for wells operates as follows. After lowering the drummer to the required depth, the wells 4-6 are filled with the fluid that is always present in the wells. Using the buttons 17-19, the operator selects the pair (s) of electrodes to which high-voltage voltage pulses are to be supplied. The moment of applying pulses to the electrodes is determined by pressing the button 20. At the same time, high voltage pulses (of the order of 40-80 kV) are applied to the selected electrodes and breakdown of the interelectrode gaps surrounded by the liquid occurs. An electrohydraulic shock occurs, the energy of which is estimated at 10-20 kJ or more, which is equivalent to an explosion of 0.834-1.7 g or more of trinitrotoluene. The spherical surfaces 7-9 form a cumulative effect, directing the impact energy either to the sides (holes 4 and 5) or down (hole 6). The fluid acts on the walls of the well, washing away the resulting deposits. Water hammer from the lower electrodes 14 acts on the reservoir, helping to increase the debit of liquid raw materials.

Practice shows that the force acting on the walls of the well is such that for their complete cleaning one, two pulses will be sufficient. Between the pulses, it is necessary to create a short time delay with the expectation that the fluid, always located at the depth of any well, will again fill the interelectrode space.

The proposed pulsed electro-hydraulic impactor has a simple design, has high strength and reliability. Its use allows to reduce the cost of carrying out work on cleaning wells, to increase the efficiency of hydroimpulse effects on the formation and significantly reduce the time of work. The versatility of the impactor is determined by the fact that with its help it is possible to widely control the force acting on the walls and, at the request of the operator, direct the impact energy in different directions.

An impactor can also be useful in releasing tools stuck during drilling.

Claims (2)

1. A universal pulsed electro-hydraulic hammer for wells, comprising a housing, working chambers filled with liquid, in which windows are made, and a drive unit, characterized in that the housing is made in the form of a sleeve with cylindrical walls and a bottom, working chambers are holes, two of which are made symmetrically on both sides in the outer walls of the sleeve, and the third hole is made in the Central part of the outer surface of the bottom, in the holes there are pairs of electrodes, separated by a gap and connected to the lower ends s high-voltage cable and the drive unit is a source of high voltage pulses to the switch that provides the sequence of supplying high voltage pulses to which are connected the upper ends of the high-voltage cable. 2. The universal pulsed electro-hydraulic hammer according to claim 1, characterized in that the hole on the outer surface of the bottom is connected to the holes made in the outer walls of the liner through channels for free flow of fluid.

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