RU186991U1 - Arrangement of underground equipment for hydraulic fracturing and simultaneous well development - Google Patents

Abstract

The utility model relates to the oil industry and can be used in the development of oil fields using hydraulic fracturing.

A device for arranging underground equipment for perforating and hydraulic fracturing, comprising an elevator for tubing, a packer, and a perforator, characterized in that a saddle with a check valve is installed above the packer to connect the annulus to the tubing internal cavity, which makes it possible to carry out all the work in one descent layout, while:

1. After perforation and hydraulic fracturing, it is possible to develop a well with a jet pump and install a jet pump on the saddle.

2. After perforation and hydraulic fracturing, it is possible to develop a well by swabbing, with a tubing check valve installed on the saddle, which is especially important for deep, directional and horizontal wells.

3. It is possible to wash backwash the remaining proppant in the tubing.

4. It is possible to equalize the pressure of the annulus and the internal cavity of the tubing and facilitate the breakdown of the packer to prevent an emergency.

All this allows you to carry out all the work in one run of the layout, while reducing energy consumption, reducing the cost of the process as a whole.

Description

The inventive utility model relates to the oil industry and can be used in the development of oil fields using hydraulic fracturing.

A known method of hydraulic fracturing and a device for its implementation (patent RU No.2007552, IPC ЕВВ 43/26, application No. 915015826, convention priority. 12/06/1991) containing a tubing string with a perforator having perforations located in one plane conducting slotted perforation, flushing the well, followed by lifting the tubing string with a perforator, lowering it with a packer and injecting fracturing and sand-bearing fluids under pressure, and before conducting slotted perforation, azimuth total orientation of the tubing string with a perforator, stabilize the tubing string from rotation, and slotted hole perforation is carried out in an azimuthally oriented and rotational position of the tubing string, while it is equipped with a tubing located on top of the perforator pipes anchor made in the form of a cylindrical body and installed in it perpendicular to its axis of the pistons with elongated along the axis of the body thrust elements on ends, and the tubing string is made with a mark on the inner surface above the anchor unit, located in the same plane with the perforation holes of the perforator.

The disadvantage of this technical solution is that in this method, the work is carried out in two stages. The first stage is the lowering of the tubing, perforator and perforation of the formation. Then the equipment is lifted. And the second stage is lowering the tubing, the packer. After the packer is planted, hydraulic fracturing is performed. The time of work is increased due to two descents and lifting of equipment, and accordingly, costs increase.

There is also known a method of hydraulic fracturing (patent RU No. 2592582, IPC ЕВВ 43/267, publ. 07/27/2016, bull. No. 21), including opening the formation with a vertical well, lowering the pipe string into the well to the interval of the formation and conducting hydraulic fracturing formation - hydraulic fracturing by injection of fracturing fluid along the pipe string; at the wellhead, the lower end of the pipe string is equipped with a slotted perforator with a check valve from below and lowered into the well in the formation interval, backwash in a half times the volume of the well, then through the slotted a drill with orientation in the azimuth of maximum stress cuts the production casing of the well and creates in the interval of the sole and roof of the formation two opposed slots with a diameter of up to 1.5 m and a slot height of 0.2-0.25 of the diameter of the well, and then in the formation between the slots through the slot the perforator by pumping the fracture fluid along the pipe string performs hydraulic fracturing with the formation of fracture cracks, after the formation of the fracture cracks, the cracks are fixed with an ultralight proppant with a density of 1200-1250 kg / m ³ , while the fracture fluid is pumped through the pipe string through the slit perforator is continued and at the same time ultralight proppant is injected into the annulus of the well under pressure not exceeding the allowable on the well walls; upon completion of the crack attachment, the pipe string with the slotted perforator and non-return valve is removed from the well.

The disadvantages of the method are that with incomplete pumping of proppant into the well (receiving "stop") it is impossible to wash proppant from the tubing, which creates an emergency.

The closest technical solution selected by the applicant as a prototype is a device for hydraulic fracturing (patent for utility model RU No. 17980, IPC ЕВВ 43/26, ЕВВ 43/114, publ. March 19, 2018, Bull. No. 8), containing a tubing string equipped with a sandblasting perforator, a check valve is installed at the bottom of which allows proppant to pass through the sandblasting perforator from the annulus, and on the tubing string in front of the sandblasting ohm fixed fiducial gidroyakor pipe and connected to each other fixedly, wherein the sleeve is fixed to fiducial gidroyakorem, as well as on a column of tubing further disposed autonomous unit gauges mounted between gidroyakorem and hydrosandblast perforator.

The disadvantage of this device is:

- firstly, the sandblasting gun has nozzles with a small cross section. The diameter of the nozzles does not exceed 6 mm. When fluid flows through the nozzles, a large hydraulic resistance arises. During hydraulic fracturing, a gel with a high viscosity is used, and it is impossible to pump this fluid (gel) in a short period of time. In this case, time is limited, since after hydraulic fracturing, the gel must decompose and leave the proppant present in the gel in the fracture formed during hydraulic fracturing;

- secondly, the fluid used for hydraulic fracturing is a complex chemical compound, and must have certain properties. Namely, hydraulic fracturing fluid is a gel-like product that contains proppant and has a specific structure and decomposes after a certain time. Passing through small openings of jetting nozzles of a sandblasting perforator destroys the gel structure and degrades the quality of hydraulic fracturing as a whole;

- thirdly, the sandblasting puncher has a small resource, it is possible to form up to 10 holes, which is very small;

fourthly, when using a sandblasting punch, it is impossible to use a packer. Full hydraulic fracturing is not possible without a packer due to high pressures during hydraulic fracturing, up to 100 MPa. Already at 10 MPa and more, poker systems are used to protect the well as a whole.

A common drawback of all of the above analogues is that after perforation and hydraulic fracturing, the well is mastered by swabbing, or by a jet pump. When swabbing, lifting of the equipment as a whole is not required. For a full-fledged swab operation, a non-return valve in the tubing is required, while for the development of a well with a jet pump, it is necessary to raise the suspension and lower the jet pump, which accordingly increases the time of work and increases economic costs.

The objective of the claimed utility model is to create a reliable, cost-effective arrangement of the layout of underground equipment, which reduces the time of work and reduces the economic costs of hydraulic fracturing, improves the quality of hydraulic fracturing and well development, and increases the reliability of underground equipment.

The technical task is solved by:

- reducing the number of hoisting operations;

- reducing the time of the technological operation;

- reducing the accident rate of the technological operation of perforation and hydraulic fracturing due to the possibility of backwashing of tubing from the remaining proppant, as a result of incomplete pumping of fracturing fluid into the wellbore.

The claimed technical result is achieved by the fact that the arrangement of underground equipment for perforation, hydraulic fracturing and well development includes an elevator for tubing, a packer, a perforator, and a seat with a check valve for communicating the annular space with the tubing internal cavity.

What is new is that a saddle with a check valve is installed above the packer to communicate the annulus with the internal tubing cavity.

New is that after perforation and hydraulic fracturing, a jet pump is installed on the saddle for well development.

New is that after perforation and hydraulic fracturing, a tubing check valve is installed on the saddle for well development by swabbing. Especially relevant for deep, directional and horizontal wells.

New is that it is possible to wash backwash remaining proppant in tubing.

New is that the pressure of the annulus and the internal cavity of the tubing is evened out and the stall of the packer is facilitated to prevent an emergency.

New is that all work is carried out in one run, which reduces the time of work and reduces economic costs.

In FIG. 1 shows a diagram of the general layout of equipment for perforation, hydraulic fracturing and well development.

The general arrangement includes tubing 1 (see FIG. 1), packer 2, hammer drill 3, saddle 4 with check valve 5.

The device operates as follows. Underground equipment for perforation and hydraulic fracturing is lowered into the well in the following sequence (see Fig. 1): perforator 3, packer 2, saddle 4 with valve 5, tubing 1. Using geophysical equipment, the perforator is installed opposite the formation being processed. With the annular gate valve open and the packer not set, perforation is performed according to the work plan. Then, when the packer is planted, hydraulic fracturing fluid (gel with proppant) is pumped into the reservoir according to the work plan. If the proppant has not completely entered the reservoir and remained in the tubing, then without tearing the packer, the proppant is washed out of the inner cavity of the tubing by backwashing through the non-return valve 5. In the usual arrangement, the entire suspension is lifted and the equipment for well development is lowered. In our case, several options for well development without raising the equipment as a whole are possible:

1. After perforation and hydraulic fracturing, a jet pump is installed on the saddle for well development. By backwashing the process fluid in the treated zone (under-packer space) they create depression and develop the well. Installation of the jet pump is carried out by dumping the jet pump into the tubing. The jet pump under its own weight is mounted on the seat ("sits" on the seat). After well development, the entire suspension is raised and the underground equipment for production is lowered.

2. After perforation and hydraulic fracturing, a tubing check valve is installed on the saddle for well development by swabbing. Especially relevant for deep, directional and horizontal wells. Installation of the tubing check valve is carried out by dumping the tubing check valve into the tubing. Next, a wellhead blowout preventer is installed for swabbing. After they start swabbing through the tubing check valve and master the well by taking fluid from the wellbore. After well development, the entire suspension is raised and the underground equipment for production is lowered.

When lifting equipment from the well after development, a packer breakdown is required. To break the packer, it is necessary to equalize the pressure in the tubing with the annulus. The presence of a check valve 5 in the arrangement ensures that the above pressures are balanced by backwashing with a constant density liquid.

Thus, the arrangement of underground equipment for perforating and hydraulic fracturing, containing an elevator for tubing, a packer, a perforator, and a saddle mounted above the packer, with a check valve for connecting the annulus and the internal tubing cavity, allows all work to be performed in one run layout, while reducing energy consumption, reducing the cost of the process as a whole.

Claims (1)

A device for arranging underground equipment for perforating and hydraulic fracturing, comprising an elevator for tubing, a packer, a perforator, characterized in that a saddle with a check valve is installed above the packer to connect the annulus and the internal cavity of the tubing.

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