Downhole pressure opening sand setting type perforation sand control pipe column

Abstract

The invention discloses an underground pressure opening sand setting type perforation sand prevention pipe column which comprises a non-channel coupling, a sand setting pipe is fixedly connected to one end of the non-channel coupling, an embossing guide pipe is fixedly connected to the other end of the non-channel coupling, a perforating gun is connected to the other end of the embossing guide pipe, and an exploder is fixedly connected to the interior of the joint of the embossing guide pipe and the perforating gun. The other end of the sand settling pipe is connected with a sand filtering pipe, and the other end of the sand filtering pipe is connected with an oil pipe; according to the underground pressure opening sand setting type perforation sand prevention pipe column, the pressure opening sand setting type perforation sand prevention pipe column is installed underground, underground mechanical sand prevention is achieved while well completion is conducted through the underground perforation pipe column, formation sand can be prevented from entering a ground production system, and the production efficiency is improved. Moreover, the sand prevention pipe column can be prevented from being put down after the perforation pipe column is lifted up after the perforation of the shallow gas well is completed, the well control risk is effectively avoided, the sand setting function in the pipe is achieved, the sand filter pipe airflow channel can be prevented from being buried by stratum sand, and the sand prevention device can be popularized and applied to underground mechanical sand prevention process technologies of various oil fields.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical sand control, and in particular relates to a downhole pressure opening sand sinking type perforating sand control pipe string. Background Art

[0002] The main perforating methods for underground operations in the Maxian block of Qinghai Oilfield are rod casting and tubing pressure perforation. During the process of replacing the bellmouth pipe string or the sand filter pipe string with rod casting, the rod of the perforating gun may be stuck in the switch position of the plug valve, resulting in the plug valve being unable to close, and there is a risk of wellhead loss of control. Therefore, tubing pressure perforation is used for underground operations in the Maxian block. Since shallow gas wells are prone to sand production, during the production of gas wells with sand, the ground gathering and transportation equipment is prone to perforation of separators and ground pipelines due to sand production from gas wells, which will cause a series of hidden dangers and problems during the production process. Therefore, the underground perforating pipe string needs to be replaced with a sand control pipe string for underground mechanical sand control. However, the perforation layer is shallow, the oil and gas rises quickly, and the well control risk of replacing the pipe string is high. Summary of the invention

[0003] The purpose of the present invention is to provide a downhole pressure opening sand settling type perforating sand control string to solve the problem that the detonator perforating gun completion string in the prior art cannot simultaneously achieve downhole mechanical sand control.

[0004] The technical solution of the present invention is: a downhole pressure opening sand settling type perforating sand control pipe string, comprising a channel-free coupling, one end of the channel-free coupling is fixedly connected to a sand settling pipe, the other end of the channel-free coupling is fixedly connected to a pressure-conducting flower pipe, the other end of the pressure-conducting flower pipe is connected to a perforating gun, and a detonator is fixedly connected inside the connection between the pressure-conducting flower pipe and the perforating gun; the other end of the sand settling pipe is connected to a sand filter pipe, and the other end of the sand filter pipe is connected to an oil pipe.

[0005] The present invention is also characterized in that:

[0006] A baffle is arranged inside the channel-free coupling.

[0007] The sand filtering device comprises an inner base pipe, an outer sand pipe is arranged on the outer periphery of the inner base pipe, the inner base pipe and the outer sand pipe are fixedly connected by a sand net, and the sand net is Z-shaped and surrounds the annular cavity formed by the outer sand pipe and the inner base pipe.

[0008] A plurality of sand filtering holes are provided on the outer surfaces of the inner base pipe and the outer sand pipe.

[0009] Both ends of the no-channel coupling are provided with threads, the no-channel coupling and the sand settling pipe are threadedly connected, and the no-channel coupling and the pressure-guiding flower pipe are threadedly connected.

[0010] The beneficial effects of the present invention are as follows: the downhole pressure-opening sand-settling perforating sand-control pipe string of the present invention is mainly used in shallow gas wells producing sand. By installing the pressure-opening sand-settling perforating sand-control pipe string in the downhole, the downhole perforating pipe string can be used to complete the well and realize downhole mechanical sand control at the same time, which can not only prevent formation sand from entering the ground production system, but also avoid the need to raise the perforating pipe string and then lower the sand-control pipe string after the perforation of the shallow gas well is completed, effectively avoiding the well control risk. At the same time, it has the function of sand settling in the pipe, which can prevent formation sand from burying the air flow channel of the sand filter pipe, and can be promoted and applied in the downhole mechanical sand control process technology of various oil fields. On the basis of the existing sand control process, the additional cost of the device is relatively low, and the cost of independently developing a channel-free coupling is only 500 yuan. The use of the device in downhole operations can save one trip of drilling and drilling operations, and save 10,000 yuan in well operations. In addition, the device is easy to obtain materials, simple in structure, and easy to install. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0012] Figure 2 It is a schematic diagram of the structure of the non-channel coupling in the present invention;

[0013] Figure 3 It is a schematic diagram of the sand filter tube structure in the present invention.

[0014] In the figure, 1. oil pipe, 2. sand filter pipe, 3. sand settling pipe, 4. non-channel coupling, 5. pressure-conducting flower pipe, 6. detonator, 7. perforating gun, 8. baffle, 9. external sand pipe, 10. internal base pipe, 11. sand screen, 12 sand filter hole. DETAILED DESCRIPTION

[0015] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0016] The present invention provides a downhole pressure opening sand settling type perforating sand control pipe string, such as Figure 1 As shown, it includes a channel-free coupling 4, one end of which is fixedly connected to a sand settling pipe 3, the other end of which is fixedly connected to a pressure-conducting flower tube 5, the other end of which is connected to a perforating gun 7, and a detonator 6 is fixedly connected inside the connection between the pressure-conducting flower tube 5 and the perforating gun; the other end of the sand settling pipe 3 is connected to a sand filter pipe 2, and the other end of the sand filter pipe 2 is connected to an oil pipe 1.

[0017] like Figure 2 As shown, a baffle 8 is arranged inside the channel-free coupling 4 .

[0018] like Figure 3 As shown, the sand filtering device 2 includes an internal base pipe 10, an external sand pipe 9 is arranged on the outer periphery of the internal base pipe 10, the internal base pipe 10 and the external sand pipe 9 are fixedly connected by a sand net 11, and the sand net 11 is Z-shaped and surrounds the annular cavity formed by the external sand pipe 9 and the internal base pipe 10.

[0019] A plurality of sand filtering holes 12 are provided on the outer surfaces of the inner base pipe 10 and the outer sand pipe 9 .

[0020] Both ends of the channel-free coupling 4 are provided with threads, the channel-free coupling 4 and the sand settling tube 3 are threadedly connected, and the channel-free coupling 4 and the pressure-guiding flower tube 5 are threadedly connected.

[0021] When the downhole pressure-opening sand-settling perforating sand-control pipe string of the present invention is working, after the downhole pressure-opening sand-settling perforating sand-control pipe string enters the well, there is a pressure-pressurizing device on the ground pump truck, and the oil pipe is firstly pressure-pressurized through the connected oil pipe 1, and the pressure enters the sand filter pipe 2 through the oil pipe 1, and the pressure is transmitted to the underground space through a plurality of sand filter holes 12 on the side of the sand filter pipe 2, and the small holes arranged on the outside of the pressure-conducting flower pipe 5 can sense the pressure in the space and transmit the pressure to the detonator 6, when the pressure reaches the detonation threshold of the detonator 6, the detonator 6 detonates, driving the perforating gun 7 to perform drilling, thereby realizing downhole pressure-pressurizing perforating, and after pressure-pressurizing perforating, the natural gas enters the oil pipe 1 for transportation after filtering the sand through the sand filter pipe 2.

[0022] The formation sand is blocked by the sand filter tube 2 and deposited in the casing pocket. The formation sand in the casing pocket is purified again through the sand settling tube 3, and finally the natural gas is transported through the oil pipeline 1. The material of the pressure-conducting flower tube 5 can be copper, iron, zinc, plastic, alloy or ceramic with good sealing and pressure resistance; the selected pleated sand filter tube 2 can filter sand from different directions, thereby improving the purity of the natural gas.

[0023] The present invention effectively reduces the probability of sand control pipe clogging, prevents formation sand from entering the production process, and prevents formation sand from damaging ground production equipment, thereby realizing mechanical sand control. The detonator 6, perforating gun 7, pressure-conducting flower pipe 5, sand settling pipe 3, sand filter pipe 2 and oil pipe 1 are threaded together through the independently developed channel-free coupling 4, and perforation and downhole mechanical sand control are realized simultaneously during the entire operation process.

[0024] Example 1

[0025] The downhole pressure opening sand-sinking perforating sand-control pipe string of the present invention is used in the Xianzhong 59 well of the Maxian block of Qinghai Oilfield as N2 2The shallow-layer gas well produced sand. In September 2022, the underground pressure-opened sand-sinking perforating sand-control pipe string was installed for plugging and adjusting the layer. The well used a 93 pressure-opening detonator and a 102 perforating gun, and perforated by tubing pressure. After the perforation was put into production, the average oil-casing pressure was 5.5 / 5.6MPa, and the average daily gas production was 8,300 cubic meters, effectively ensuring the smooth entry and external transmission of 531,000 cubic meters of natural gas. Through sand production monitoring, the sand production of the well was 0 kg, and the sand control effect was good. After the installation of the device in Xianzhong 59 Well, the well was completed with the downhole perforating pipe string and mechanical sand control was carried out underground, which not only prevented the formation sand from entering the ground production system and damaging the ground equipment, but also avoided the perforating pipe string after the shallow gas well was perforated and then the sand control pipe string was lowered, effectively avoiding the well control risk. The underground operation process saves one trip of drilling and drilling operations, saving 10,000 yuan in operating costs.

[0026] Example 2

[0027] The downhole pressure opening sand settling perforating sand control pipe column of the present invention, the oil pipe 1 adopts the model of Ф73mm oil pipe, the sand filter pipe 2 adopts the pleated precision sand filter pipe, which is a high-precision filter medium plus a multi-layer high-strength corrosion-resistant stainless steel precision filter mesh combination structure, and the whole is processed into an annular pleated body. Compared with the conventional sand control pipe, the flow area of ​​the pleated sand filter pipe is more than 5 times that of the ordinary sand control pipe, which reduces the probability of sand control pipe blockage and extends the production cycle of the gas well to the greatest extent. After studying the sandstone and siltstone with the main particle size value of the formation sandstone between 3.906 and 500μm, the present invention adopts the sand filter pipe 2 with a sand filtering accuracy of 25μm; the sand settling pipe 3 adopts the Ф73mm sand settling pipe, which can prevent Stop the formation sand and bury the sand filter pipe air flow channel, 102 perforating gun; the homemade channel-free coupling 4 of the present invention uses a Ф73mm homemade channel-free coupling, which can withstand a pressure of 35MPa and meet the production requirements of high-pressure gas wells; the homemade channel-free coupling 4 can thread the pressure-conducting flower pipe 5 and the downhole sand sinking pipe 3; the detonation pressure of the selected 93 pressure opening detonator 6 is 15MPa-20Mpa; the model of the pressure-conducting flower pipe 5 is a Ф73mm pressure-conducting flower pipe; the cost of independently developing the channel-free coupling 4 is only 500 yuan. The use of this device in downhole operations can save one trip of drilling operations and save 10,000 yuan in well operations. In addition, the device is easy to obtain materials, simple in structure, and easy to install.

[0028] Example 3

[0029] The downhole pressure opening sand-settling perforating sand-control pipe string of the present invention comprises a channel-free coupling, one end of the channel-free coupling is fixedly connected to a sand-settling pipe, the other end of the channel-free coupling is fixedly connected to a pressure-conducting flower pipe, the other end of the pressure-conducting flower pipe is connected to a perforating gun, and a detonator is fixedly connected inside the connection between the pressure-conducting flower pipe and the perforating gun; the other end of the sand-settling pipe is connected to a sand filter pipe, and the other end of the sand filter pipe is connected to an oil pipe.

Claims

1. Downhole pressure opening sand settling type perforating sand control string, characterized by: The invention comprises a channel-free coupling (4), one end of which is fixedly connected to a sand settling pipe (3), the other end of which is fixedly connected to a pressure-conducting flower tube (5), the other end of which is connected to a perforating gun (7), and a detonator (6) is fixedly connected inside the connection between the pressure-conducting flower tube (5) and the perforating gun (7); the other end of the sand settling pipe (3) is connected to a sand filter pipe (2), and the other end of the sand filter pipe (2) is connected to an oil pipe (1).

2. The downhole pressure-opening sand-sinking perforating sand-control pipe string according to claim 1, characterized in that: A baffle (8) is arranged inside the channel-free coupling (4).

3. The downhole pressure-opening sand-sinking perforating sand control string according to claim 1, characterized in that: The sand filter device (2) comprises an internal base pipe (10), an external sand pipe (9) is arranged on the outer periphery of the internal base pipe (10), the internal base pipe (10) and the external sand pipe (9) are fixedly connected via a sand net (11), and the sand net (11) is Z-shaped and surrounds an annular cavity formed by the external sand pipe (9) and the internal base pipe (10).

4. The downhole pressure-opening sand-sinking perforating sand control string according to claim 3, characterized in that: The outer surfaces of the inner base pipe (10) and the outer sand pipe (9) are both provided with a plurality of sand filtering holes (12).

5. The downhole pressure-opening sand-sinking perforating sand control string according to claim 1, characterized in that: The two ends of the channel-free coupling (4) are provided with threads, the channel-free coupling (4) and the sand settling tube (3) are threadedly connected, and the channel-free coupling (4) and the pressure-conducting flower tube (5) are threadedly connected.

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