RU2302514C2 - Well pumping screen - Google Patents

Abstract

FIELD: oil production, particularly filters for oil cleaning of mechanical impurities to be used during oil and gas production from wells characterized by sand withdrawal from reservoir.

SUBSTANCE: pumping screen comprises perforated pipe and filtering mesh wire enclosing outer surface of perforated pipe. The pumping screen includes two main parts, namely filtering and connection ones. The filtering and connection parts are secured one to another through clutch. Filtering part is made as perforated pipe with slot-like orifices having widths equal to 0.04-0.05 of inner pipe diameter and lengths equal to 1.5-2.0 inner pipe diameters. Connection part is made as perforated pipe with perforations having diameters equal to 0.2-0.22 of outer pipe diameter and summary perforation area equal to 20-30% of total connection part area. Bush is welded to connection part pipe body. The bush is provided with threaded connection to receive rubber sealing rings having diameters 3-5 mm greater than inner well diameter and with gaskets pressed with annular screw-nuts and fixed with lock-nut.

EFFECT: increased efficiency of produced oil cleaning of mechanical impurities.

3 cl, 1 dwg

Description

The invention relates to filters for oil purification from solids and is used in the field of oil and gas production from wells complicated by sand removal from the formation.

Known well filter, which is used in the production of liquid or gaseous product from wells, namely for filtering oil, water or gas at subhorizontal sections of the barrel. The downhole filter for the subhorizontal section of the barrel is made in the form of a perforated pipe with slotted holes, located below the packer on the casing string with spring centralizers at each coupling connection, slotted holes with a width of 0.1-0.3 mm and a length of 100-150 mm are made by plasma cutting and arranged in an arc of a circle in rows along the length of the pipe. In this case, the slit openings can be arranged in circular rows of six slit openings in a row with a row offset of 30 ° relative to each other while providing a cross-sectional area of the filter part per unit length of the pipe (RF patent No. 2199652, IPC 7 Е21В 43/08, Е03В 3 / 18, 2003).

The disadvantage of this design is the high manufacturing cost, low throughput of the slit holes, resulting in a rapid clogging of the through holes with particles of sand and gravel, which reduces the productivity of the well.

Of the known inventions, the closest is a downhole filter used to filter the product extracted from oil, water and gas wells. The device includes a perforated pipe with a sleeve and a metal mesh. It covers the outer surface of the perforated pipe. The perforated pipe on its outer surface is made with ribs arranged in a spiral with a pitch. The ribs increase the resistance to crushing when lowering the filter into deviated and horizontal wells, and also serve to preserve the placed metal mesh between them with a wire winding (RF patent No. 2097533, IPC 6 ЕВВ 43/08, 1997).

The disadvantages of the prototype are: the complexity of the design of the filter, the lack of efficiency of capture of mechanical impurities and the lack of a centering device.

The objective of the invention is to provide a downhole pump filter (FSN), which technically solves the problem of filtering produced oil from mechanical impurities.

The problem is solved in that in a downhole pump filter containing a perforated pipe and a filtering metal mesh covering the outer surface of the perforated pipe and made of two main parts: filtering and connecting, which are fixed to each other with a sleeve, according to the invention, the filtering part is perforated a pipe with slotted openings of a width of 0.04-0.05 and a length of 1.5-2.0 of its inner diameter, and the connecting part is a perforated pipe with openings for with a meter 0.2-0.22 of its outer diameter and an occupied area of 20-30% of the entire surface of the connecting part, a sleeve with a threaded connection is welded to the body of the pipe of the connecting part to install rubber o-rings, the outer diameter of which is 3-5 mm larger internal diameter of the well, with gaskets clamped by a round nut and fixed by a lock nut. In the filter, a woven metal mesh is installed in several layers. The filter is equipped with an additional filtering part to increase the throughput for high-yield wells.

The drawing shows a diagram of a downhole pump filter with operating units and the following notation:

I - filtering part, II - connecting part, 1 - perforated filtering pipe, 2 - filtering metal mesh, 3 - clamps, 4 - plug, 5 - perforated connecting pipe, 6 - sleeve, 7 - O-rings, 8 - gaskets, 9 - nut, 10 - lock nut, 11 - coupling, 12 - ribs.

The device operates as follows.

The downhole pump filter is connected by means of a threaded connection to the lower threaded part of the ESP motor and lowered with the installation of the ESP in an oil well. The produced oil passes through the filtering part II of the FSN, consisting of a perforated pipe 1 and a filtering metal mesh wound around it 2. Rubber sealing rings 7 separate the crude crude oil from the purified oil, then the filtered oil enters the connecting part I of the FSN, which is a perforated pipe 5, through the holes in the pipe 5 is fed to the ESP.

The technical and economic advantages of this invention include:

1. FSN is made of two main parts, filtering and connecting, for ease of operation and cost reduction.

2. FSN can be equipped with several filter parts to increase throughput.

3. Additional functions during the operation of the FSN are performed by rubber sealing rings with gaskets. They serve to damp vibrations and to prevent the breakdown and fall of the ESP or all of the deep pumping equipment into the bottom of the well.

Claims (3)

1. A downhole pump filter containing a perforated pipe and a filtering metal mesh covering the outer surface of the perforated pipe and made of two main parts: a filtering and connecting one, which are fixed to each other by means of a sleeve, characterized in that the filtering part is a perforated pipe with slotted holes with a width of 0.04-0.05 and a length of 1.5-2.0 from its inner diameter, and the connecting part is a perforated pipe with holes with a diameter of 0.2-0.22 from its outer diameter and an occupied area of 20-30% of the entire surface of the connecting part, a sleeve with a threaded connection is welded to the pipe body of the connecting part to install rubber o-rings, the outer diameter of which is 3-5 mm larger than the inner diameter of the well, with gaskets clamped round nut and fixed locknut. 2. The filter according to claim 1, characterized in that the woven metal mesh is installed in several layers. 3. The filter according to claim 1, characterized in that it is equipped with an additional filter part to increase the throughput for high-yield wells.