RU2140533C1 - Plant for pulse stimulation of pool - Google Patents

Abstract

FIELD: oil production. SUBSTANCE: plant has tubing with cylinder lowered into well. Cylinder accommodates piston connected by means of rod with pumping unit. Piston has check valve and ports. Lower end of cylinder is closed with movable plug. When plunger moves upwards, zone of decreased pressure is formed in cylinder hollow and fluid is drawn thereto through ports after their coming out of cylinder. Fluid flow strikes plug bottom. Plug is made in form of sleeve. Pulse from fluid strike is transmitted through fluid in well to producing formation. EFFECT: reduced losses of energy in transmitting pulses to well. 2 cl, 1 dwg

Description

 The invention relates to the field of exploitation of oil fields using pulsed wave exposure to oil-saturated reservoirs.

 A known installation for pulsed exposure to a reservoir containing a tubing string installed in a well with an anvil on a shoe, a falling load placed in the string and a mechanism for lifting the load [1].

 The disadvantage of the installation is that it needs a special drive. In addition, the falling load does not provide an even distribution of the shock load on the column shoe, which can lead to its destruction.

 Closest to the claimed installation is a device for pulsed impact on the bottom-hole zone of wells with a shock wave, containing a tubing string with a pipe, a plunger with a check valve and a shut-off element with a spring-loaded valve and radial channels located in the tubing string [2].

 The disadvantage of this device is that a significant part of the pulse energy generated in the tubing is extinguished in the shut-off element.

 The technical challenge facing the invention is to reduce energy loss during the transmission of pulses from the tubing string into the well and then into the reservoir.

 To solve this problem, an installation for impulse action on a reservoir containing a tubing string installed in a well with a cylinder and a plunger connected by a string of booms to a pumping unit so that the cavity of the tubing string is connected to the cavity at the top of the plunger stroke the cylinder is further provided with a plug mounted coaxially with the possibility of reciprocating motion on the cylinder or in its cavity.

 The plunger is made with a check valve, below which windows can be made in it, and the working stroke of the rocking machine at the upper point ensures the exit of the plunger windows from the cylinder. In the absence of windows, the plunger leaves the cylinder completely.

 The plug accepts the impact of the falling fluid column and transmits the impulse directly to the fluid in the well. The mobility of the plug and direct contact with the fluid in the well contribute to the maximum conservation of the energy of the pulse excited in the tubing string.

 The cap can be made in the form of a glass.

 The drawing shows the installation diagram for a pulsed impact on the reservoir.

 The installation comprises a tubing string 2 installed in the well 1 with a cylinder 3 and side holes 4. A plunger 5 with a check valve 6 and windows 7 located below the valve 6, connected by a column of rods 8 with a rocking machine 9, is placed in the cavity of the cylinder 3 mounted on the surface. The exit from the cylinder 3 from the lower end is blocked by a plug 10, made in the form of a glass and mounted on the cylinder with the possibility of reciprocating motion. The plug may be spring loaded. In the absence of a spring, the plug is pressed upward by excess pressure from the side of the well cavity.

 At its lower point, the plunger 5 is located at the very bottom of the glass 10 and when it moves upward in the pipe cavity, bounded by the bottom of the glass (plug) and valve 6, a zone of reduced pressure is formed. If holes 4 are not made in column 2, then the pressure in the cavity of the column above the plunger will increase.

 The design shown in the drawing is designed so that, when it arrives at the top point, the plunger 5 leaves the cylinder 3 by the windows 7 and completely releases the liquid inlet from the column 2. The liquid rushes into the opened cavity, the pressure of which is much lower. The momentum from the impact of the liquid column on the bottom of the glass is transmitted through the liquid in the well to the reservoir.

 Plunger 5 can be made without windows, but then at the top point it should completely exit the cylinder.

 The impact of a liquid column into the plug causes elastic vibrations in the formation, affecting stagnant and low-permeability zones and contributes to their more intensive involvement in development.

Sources of information:
1. RF patent N 2075596, cl. E 21 B 43/25, 1997.

 2. Copyright certificate of the USSR N 1719623, cl. E 21 B 43/25, 1989.

Claims (2)

 1. Installation for pulsed impact on the reservoir, containing a tubing string installed in the well with a cylinder, a plunger with a check valve placed in the cylinder and a rocking machine connected by a string of rods to the plunger so that a message is provided at the top of the plunger stroke with a cavity of the tubing string, characterized in that it is equipped with a plug mounted coaxially with the possibility of reciprocating movement on the cylinder or in its cavity and in contact with edstvenno with downhole fluid.  2. Installation for pulsed exposure according to claim 1, characterized in that the plug is made in the form of a glass.