RU2645397C1 - Hydraulic pump filter - Google Patents

Abstract

FIELD: soil or rock drilling.

SUBSTANCE: invention relates to the construction of oil and gas wells, namely to devices for retaining mechanical impurities in drilling or grout mix. Device includes a body with threads at the ends on which the upper and lower connecting units are fixed. In the axial channel of the body, a filter tube and a stream swirler are installed in the form of a cylinder with a conical axial hole and an internal helical spiral channel. At the upper end of the filter tube a fairing is placed equipped with a flow turbulator consisting of a rod, the upper end of which has a helical spiral cutting. Lower end of the rod is made spherical and is installed in the boring of the fairing with fixation of the nut. In the middle part on the rod a number of transverse slits are arranged, staggered in height. Stream swirled is made from elastic material.

EFFECT: effective operation time of the filter increases, hydraulic flow resistance reduces, the reliability and durability of the filter increases.

1 cl, 1 dwg

Description

The invention relates to the construction of oil and gas wells, and in particular to devices for retaining mechanical impurities in the composition of drilling or grouting solutions.

A known filter design in the form of a perforated tubular frame (see Gavrilko V.M. Drillhole Filters. / Second Publishing. / Moscow, "Nedra", 1976, p. 5-8).

The design of the filter is a pipe on which a series of perforations are made, placed in a checkerboard pattern. A connecting element is installed on the upper end of the pipe, and the lower end is provided with a connecting thread for mounting plugs on it.

The filter itself is installed in the axial channel of the drill pipe string. The flow of flushing fluid or drilling fluid is fed into the pipe filter and through the perforations in its body flow into the annular gap between the pipe wall of the drill string and the outer surface of the filter. The number of perforations and their arrangement are determined based on the estimated flow rate of the drilling fluid.

Sludge and solids settle over the plug in the axial channel of the filter.

The disadvantages of the design include:

- when sludge accumulates in the axial channel of the pipe filter, the drilling fluid is shut off to the lower rows of holes, with a corresponding increase in the flow rate through the remaining holes, which leads to accelerated abrasive wear of the structure and termination of the drilling process.

A known design of the filter installed on the suction line of mud pumps (see Akhmadishin F.F. Trial use of the filter on the suction line of mud pumps. / FF Akhmadishin, V.E. Pronin, S.L. Bagnyuk. / Collection of scientific papers TatNIPIneft Issue No. LXXX, Moscow, 2012, pp. 182-186.

The filter consists of a perforated pipe with a tip on the lower end and a hole on the upper to ensure removal of the filter from the installation site.

A thrust ring is installed on the outer surface of the filter, with which it rests on the inner protrusion in the axial channel of the pipeline.

The diameter of the perforation holes on the pipe is taken equal to 4 ÷ 5 mm, with the location of the holes in a checkerboard pattern.

The disadvantage of the design is the low efficiency of work, which consists in the rapid clogging of the perforation holes with cord fiber and the passage of part of these fibers in the turbodrill section, with their clogging and stopping the drilling process.

This is also associated with the presence of stagnant zones and a change in the mode of flow of the drilling fluid in the perforations, with a change in the speed and intensification of abrasive processes.

A known filter design for a drill string (see RF patent No. 2016186, IPC E21B 21/00. Filter with a bypass assembly. Announced on 06/03/1991. Published on 07/15/1994), designed to clean the drilling fluid from mechanical impurities, when it feed to hydraulic motor or chisel. The device consists of a hollow body, with threads for connecting, a filter module, a tubular casing, in the axial channel of the hollow body, with the formation of an annular cavity for receiving mechanical impurities.

The disadvantages of the design include the fact that:

- when sediment accumulates in the annular gap, the flow regime of the process fluid changes in the direction of increasing speed and intensifying abrasive wear processes;

- with the accumulation of mechanical particles in the annular gap, there is a overlap of the living section of the perforation holes with sludge, which will lead to an increase in the pressure drop across the filter pipe and its collapse. Moreover, the greater its duty cycle, the smaller the pressure drop is necessary to crush it.

Changing the direction of supply from the inside of the filter pipe into the annular gap is not provided.

The presence of mechanical contact with the inner surface of the drill pipe, according to the authors, leads to a vibration effect on the flow of the process fluid, which helps to clean the perforations from mechanical impurities.

A known design of the drill string filter (see RF patent No. 2429342, IPC E21B 43/08. Filter for a drill string with a hydraulic downhole motor. Declared December 28, 2009, published September 20, 2011), adopted by the authors as a prototype.

The drill string filter includes a hollow body, with threads at the ends, a filter module for the drilling fluid, a tubular casing installed in the hollow body, forming a cavity for receiving and accumulating mechanical particles. The filter tube has a series of perforations fastened by the inlet end to the cutoff.

Inlet and outlet bushings, with annular grooves for installing o-rings.

The output sleeve is provided with a centering belt for contact and support on the narrowing in the hollow body.

An exhaust element in the form of a hook is fixed at the end of the fairing.

The device is inserted into the axial channel of the drill pipe string before being installed on the end surface in the narrowing.

Below, a hydraulic motor with a chisel for drilling wells is connected to the device.

The flow of drilling fluid through the drill pipe string is fed through the filter module bypassing the fairing into the annular gap and through the perforation holes enters the filter pipe and then enters the hydraulic motor cavity. Mechanical impurities-scale, metal, polymer and rubber particles settle in the annular gap, when completely filled, a pressure jump occurs. This is a signal to remove the filter module from the well along with the drill pipe string.

The disadvantages of the design include:

- the complexity of the design, with a decrease in the annular gap between the filter pipe and the hollow body, due to the introduction of a tubular casing, which accordingly reduces the amount of annular space for the accumulation of sludge;

- the implementation of a cylindrical filter pipe leads to an uneven supply of drilling fluid to each perforation hole in height;

- clogging of perforation holes with sludge is not provided with constructive devices for cleaning them, when forming arched structures.

The technical result that can be obtained by implementing the invention:

- the excitation of hydrodynamic pulses in the flow of the drilling fluid contributes to the destruction of arched structures on the perforations of the filter pipe;

- the imposition of vibrations on the housing and the filter pipe contributes to a more dense packing of sediment in the annulus and in-tube space, which increases the effective time of the filter;

- installation of a flow swirl with a conical hole tapering towards the outlet, helps to eliminate stagnant zones and reduce hydraulic resistance of the flow;

- the execution of the swirl made of elastic material helps to reduce the abrasive wear of the parts of the connection node and the housing.

The technical result is achieved in that the hydraulic pump filter consists of a housing with threads at the ends, equipped with connecting elements, a filter module in the form of a filter pipe with perforations and a fairing at the end. A flow swirl is installed in the axial channel of the housing, in the form of a cylindrical sleeve with a conical axial hole, with a spiral spiral channel inside.

The fairing is equipped with a flow turbulator in the form of a rod, on the upper end of which a spiral spiral thread is made, and the lower end has the shape of a ball mounted in the fairing bore and tightened with a nut. In the middle part, a number of transverse slots are made on the rod, placed in a checkerboard pattern, forming together an oscillatory circuit. The fairing bore is connected by a drainage hole, with the axial channel of the filter pipe.

The swirl flow is made of elastic material and fixed by the elements of the connecting node.

The design of the filter is shown in section, where:

- in the drawing - a General view of the layout, with connecting nodes at the ends.

The design of the device includes a housing 1, with connecting upper 2 and lower 3 nodes.

A flow swirl 5 is installed in the axial channel 4 of the housing 1, in the form of a cylindrical sleeve with an axial conical hole 6 expanding in the direction of the perforated filter pipe 7. On the inner conical surface of the flow swirl 5 is made a spiral spiral channel 8, for twisting the flow to the inner wall of the housing 1 A fairing 9 is installed at the upper end of the filter pipe 7 with a bottom 10 provided with a flow turbulator 11 located in the axial channel 4 of the housing 1. The turbulator 11 is made in the form of an oscillating circuit 12, representing a rod 13 with a number of transverse slots 14 placed in a checkerboard pattern around the perimeter.

At the upper end of the rod 13, helical spiral cutting 15 is made, for directing and twisting the flow, when it is fed into the axial channel of the upper connecting unit 2.

The swirl flow 5 is fixed between the elements of the upper connecting node 2 and the housing 1 and is made of an elastic material, such as rubber.

At the lower end, the rod 13 is provided with a ball 16, which is installed in the bore of the tip 9 and is tightened by a nut 17. A drain hole 18 is made in the bottom 10 of the cowling 9, which extends into the axial channel 4 of the housing 1. The diameter of the drain hole 18 in the bottom 10 is comparable to the diameter of the perforations on the filter pipe 7.

The principle of operation of the device

By connecting the upper 2 and lower 3 nodes, the device is installed as part of the supply pipe from the mud pump to the drill pipe string, with the drilling fluid being pressurized into the axial channel of the filter pipe 7, from where through the perforations in its body it enters the annular gap between the housing 1 and the filter pipe 7. Next, the flow passes into the axial channel 4 of the housing 1, from where it enters the conical axial hole 6 of the swirler 5 and the screw groove 8, which leads to rotation of the flow, with the passage through the axial channel of the upper Interconnect assembly 2 to the pipeline.

This stimulates oscillatory movements on the turbulizer 11, with the excitation of hydrodynamic pulses in the pumped stream. Sludge particles settling in the area of perforations inside the filter pipe 7 cannot create a stable arched structure that impedes the normal filtration of the drilling fluid through the device. When excited in the flow of hydrodynamic and mechanical vibrations, due to the operation of the turbulator 11, a denser packing of sludge occurs in the axial channel of the filter pipe 7.

When the axial channel of the filter pipe 7 is completely filled with slurry, pressure increases in the pipeline, which serves as a signal for removing the filter from the installation site and cleaning it from the slurry.

Oscillatory movements of the turbulator 11 are both axial and radial, due to the ball connection 16 with the fairing 9 and the presence of transverse slots 14 on the body of the rod 13.

Claims (2)

1. The filter of the hydraulic pump, comprising a housing with threads at the ends, a filter module in the form of a filter pipe with perforations and a fairing at the end installed in the axial channel of the housing, with the formation of an annular gap, characterized in that the device is equipped with a swirl flow in the axial channel of the housing made in the form of a cylindrical sleeve with a conical axial hole, on the inner surface of which a helical spiral channel is made, the fairing is equipped with a flow turbulator in the form of a rod, on top at the end of which a helical spiral cut is made, in the middle part on the rod there are a number of transverse slots arranged in a checkerboard pattern, and the lower end in the form of a sphere is mounted in the fairing bore and tightened with a nut, and the bore is hydraulically connected by a drainage hole to the axial channel of the filter pipe. 2. The hydraulic pump filter according to claim 1, characterized in that the flow swirl is made of an elastic material and is fixed by elements of the connecting unit mounted on the thread of the housing.

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