Underground cooling device for oil field drilling by utilizing chemical reaction

Abstract

The invention belongs to the field of oil field drilling and other related underground cooling tools, and discloses an underground cooling device for oil field drilling by utilizing chemical reaction. Comprising a shell body, a high-pressure cavity, a temperature sensing controller, a piston ring, a medicine cavity, a one-way medicine adding opening, a one-way medicine outlet, an inner wall and an outer wall. A high-pressure cavity and a medicine cavity are arranged between the shell main body and the inner wall and are separated by a piston ring, the temperature sensing controller is arranged on the shell main body at the end part of the high-pressure cavity, the one-way medicine feeding port is arranged on the shell main body at the end part of the medicine cavity, and the one-way medicine outlet is arranged on the inner wall at the end part of the medicine cavity. The device is remarkable in cooling effect, the well bottom temperature of 140 DEG C can be reduced by 10-30 DEG C according to different cooling drugs, the service life of an instrument can be greatly prolonged, and the use stability of the instrument can be greatly improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of oilfield drilling and other related downhole temperature reducing tools, and particularly relates to a downhole temperature reducing device for oilfield drilling using chemical reaction. BACKGROUND

[0002] In the process of oilfield development, the reservoirs in many areas are deeply buried, and the formation temperature can reach more than 150 degrees Celsius. In such a high-temperature environment, the internal components of downhole drilling instruments and other devices will fail due to high temperature, resulting in high instrument failure rate during drilling operation, frequent tripping to replace instruments, especially in the process of horizontal well drilling, as the well depth increases, the bottom hole temperature is higher, causing serious waste of manpower and material resources, increasing the drilling cycle, greatly increasing the drilling cost, and increasing the probability of downhole complex conditions, which seriously restricts the development of oilfield benefits.

[0003] Currently, oilfields mainly use two ways to solve the problem of downhole high temperature and reduce the impact of downhole high temperature on the drilling process. One is to use high-temperature-resistant downhole drilling instruments. Currently, domestic and foreign high-temperature-resistant instruments can withstand 150 degrees Celsius, but the actual temperature exceeds 135 degrees Celsius, and the instrument will frequently malfunction, making it difficult to meet the drilling needs of high-temperature formations. Moreover, high-temperature-resistant instruments are relatively scarce, and there are often situations where the use of high-temperature-resistant instruments is delayed due to the lack of such instruments on site. In some cases, it takes more than 20 days to have a high-temperature-resistant instrument available. The second way is to use ground cooling equipment such as air cooling or water cooling to reduce the temperature of the circulating drilling fluid. This method can reduce the temperature of the ground drilling fluid by 20-30 degrees Celsius, but as the well depth increases, especially in horizontal wells, the downhole temperature increases rapidly, and the effect of ground temperature reduction is basically offset as the downhole temperature increases. In summer, the cooling effect of ground cooling equipment is also poor, and the application effect cannot meet the needs of drilling.

[0004] Drilling shafts are different from mine shafts. Drilling shafts are deeper and have smaller spaces, so large cooling equipment cannot be used in downhole. After investigation, there are currently downhole cooling tools for drilling that use semiconductor cooling tools, Stirling coolers, and conventional refrigerators that use a single or series of connected compressors and evaporators for circulation. However, these methods require modification of the instruments that need to be cooled in downhole, such as single-point or short-temperature reduction, which is occasionally used in some high-temperature-resistant instruments, but the actual use effect is not good. SUMMARY

[0005] In order to overcome the shortcomings of the existing technology, the present invention provides an in-hole cooling device for oilfield drilling that utilizes chemical reactions. The tool is intelligent, simple, stable and reliable. It can be lowered into the wellbore along with the drill bit. During the drilling process, when the downhole temperature reaches above the set temperature, it automatically releases a chemical agent that can reduce the temperature of the wellbore drilling fluid, thereby reducing the temperature of the entire wellbore space below the tool, thereby protecting the downhole instruments, increasing the instrument service life, and shortening the drilling cycle.

[0006] The above-mentioned object of the present invention is achieved by the following technical solution: a downhole cooling device for oilfield drilling utilizing a chemical reaction, comprising a housing, a high-pressure chamber, a temperature sensor controller, a piston ring, a chemical chamber, a one-way chemical dosing port, a one-way chemical discharge port, and an inner wall. A high-pressure chamber and a chemical chamber are defined between the housing and the inner wall, the high-pressure chamber and the chemical chamber being separated by the piston ring. The temperature sensor controller is disposed on the housing at the end of the high-pressure chamber, the one-way chemical dosing port is disposed on the housing at the end of the chemical chamber, and the one-way chemical discharge port is disposed on the inner wall at the end of the chemical chamber.

[0007] Furthermore, the downhole cooling device for oilfield drilling using chemical reaction is 9.8 m long.

[0008] Furthermore, the downhole cooling device for oilfield drilling using chemical reaction has a buckle shape of 410*411, an outer diameter of 184.2 mm, and an inner diameter of 57.2 mm.

[0009] Furthermore, the inner wall thickness of the downhole cooling device for oil field drilling using chemical reaction is 6 mm.

[0010] Furthermore, the total length of the high-pressure chamber and the chemical chamber of the downhole cooling device for oil field drilling using chemical reaction is 8.8m.

[0011] Furthermore, the volume of the high-pressure chamber and the drug chamber of the oil field drilling downhole cooling device using chemical reaction is 0.2m 3 The maximum volume of the drug cavity is 0.15m 3 .

[0012] Furthermore, the temperature sensor controller is connected to the medicine outlet switch by a built-in connecting line. The temperature sensor controller controls the switch state of the medicine outlet according to the set temperature. The temperature sensor controller and the switch are powered by their own batteries.

[0013] Furthermore, the downhole cooling device for oilfield drilling using chemical reactions can store drugs such as ammonium chloride, ammonium nitrate or potassium nitrate.

[0014] The downhole temperature reducing device for oil field drilling by using chemical reaction adds the medicine into the medicine storage space through the medicine adding hole on the ground, the energy is stored in the high pressure cavity during the medicine adding process, the temperature sensor is arranged on the ground, the medicine outlet is opened when the temperature sensor value is 132℃, and the medicine outlet is closed when the temperature sensor value is 125℃, the temperature reducing tool is connected to the upper position of the instrument which needs to be cooled, the temperature sensor controller controls the medicine outlet to be opened when the temperature of the downhole reaches the set value, the medicine is pushed into the water eye of the tool through the medicine outlet under the high pressure of the cavity, and the heat absorption reaction occurs between the medicine and the water in the water eye, so that the temperature of the lower drilling fluid is reduced. When the temperature of the drilling fluid is reduced to the set value, the temperature sensor controller controls the medicine outlet to be closed. Through the intermittent work, the temperature of the drilling fluid at the lower part of the temperature reducing tool is reduced, and the lower instrument can work in the high temperature state, the instrument can be protected, the service life of the instrument is prolonged, the frequency of tripping and replacing the instrument is reduced, the cycle is shortened, and the economic benefit is improved.

[0015] Compared with the prior art, the application has the beneficial effects that: a device for storing and releasing temperature-reducing chemicals is provided, a one-way medicine outlet is opened when the downhole temperature reaches the set value, and the chemicals in the storage space are released into the wellbore under the pressure of the air bag, so that the heat absorption reaction occurs between the chemicals and the drilling fluid, and the temperature in the wellbore is reduced. The temperature reducing effect of the device is remarkable, and the bottom hole temperature of 140℃ can be reduced by 10-30℃ according to different temperature-reducing chemicals, so that the service life and stability of the instrument can be greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0016] The application will be further described below in combination with the drawings and specific embodiments

[0017] Figure 1 Figure 1 is a longitudinal sectional view of the standby state of the downhole temperature reducing device for oil field drilling by using chemical reaction of the application;

[0018] Figure 2 Figure 2 is a longitudinal sectional view of the chemical releasing state of the downhole temperature reducing device for oil field drilling by using chemical reaction of the application;

[0019] Figure 3 Figure 3 is a sectional view of the medicine outlet of the downhole temperature reducing device for oil field drilling by using chemical reaction of the application;

[0020] Figure 4 Figure 4 is a middle sectional view of the downhole temperature reducing device for oil field drilling by using chemical reaction of the application.

[0021] In the figure, 1 is an outer shell body, 2 is a high pressure cavity, 3 is a temperature sensor controller, 4 is a piston ring, 5 is a medicine cavity, 6 is a one-way medicine adding port, 7 is a one-way medicine outlet, and 8 is an inner wall. DETAILED DESCRIPTION

[0022] The application will be described in more detail by specific examples, but the protection scope of the application is not limited. Unless otherwise specified, the experimental methods used in the application are conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0023] Reference Description Figures 1-4 The application provides a downhole temperature reducing tool for oil field drilling and related fields. The tool mainly comprises a shell, a high-pressure cavity, a temperature sensing controller, a piston ring, a medicine cavity, a one-way medicine inlet, and a one-way medicine outlet. The tool has a shell and an inner wall, and has small water eyes in the tool. Spaces are reserved for the medicine cavity and the high-pressure cavity. The length, outer diameter, and buckle type can be adjusted according to the borehole size and drilling tools. The tool is made of high-pressure-resistant and torsion-resistant materials. A wear-resistant band can be added to the shell to improve the stability of the tool. The high-pressure cavity and the medicine cavity are separated by the piston ring. The medicine inlet and the medicine outlet are one-way ports. The temperature sensing controller can control the opening and closing of the medicine outlet. According to the type of liquid in the well, the corresponding medicine is stored in the tool. By adding the medicine and the liquid in the well, an endothermic chemical reaction is generated to reduce the downhole temperature.

[0024] Example 1

[0025] Before using the device, the drilling fluid system and the medicine used need to be determined. According to the liquid or medicine in the well, the medicine added to the tool is determined. The medicine is added to the medicine cavity 5 through the medicine inlet 6 on the ground, and the high-pressure cavity 2 is compressed to store pressure (the pressure is calculated according to the vertical depth of the used well section). The temperature at which the temperature sensing controller needs to be opened is set. After the preparation is completed, the tool is connected to the drilling tool. The installation position is determined according to the position of the instrument that needs to be cooled and protected. When the downhole temperature reaches the set value of the sensor, the temperature sensing controller 3 controls the medicine outlet 7 to open. Under the pressure of the high-pressure cavity, the medicine in the medicine cavity 5 slowly enters and exits the water eyes of the drilling tool, and contacts with the corresponding liquid or medicine to perform an endothermic chemical reaction, thereby reducing the temperature of the fluid in the water eyes of the drilling tool and protecting the lower instrument. When the temperature of the drilling fluid in the well is lower than the temperature set by the temperature sensor, the medicine outlet is closed, and the medicine in the tool stops entering the water eyes of the drilling tool.

[0026] The above-described embodiments are only preferred embodiments of the application, and not all the embodiments that can be implemented by the application. Any obvious modifications made by those skilled in the art without departing from the principles and spirit of the application should be considered within the scope of protection of the claims of the application.

Claims

1. A downhole temperature reducing device for oil field drilling using a chemical reaction, characterized by, Including shell body (1), high pressure cavity (2), temperature sensor controller (3), piston ring (4), medicine cavity (5), one-way medicine adding port (6), one-way medicine outlet (7), inner wall (8), the shell body (1) with inner wall (8) have high pressure cavity (2) and medicine cavity (5), high pressure cavity (2) and medicine cavity (5) are separated by piston ring (4), temperature sensor controller (3) is located on the end of high pressure cavity (2) shell body (1), one-way medicine adding port (6) is located on the end of medicine cavity (5) shell body (1), one-way medicine outlet (7) is located on the end of medicine cavity (5) inner wall (8).

2. The downhole temperature reducing device for oil field drilling using chemical reaction according to claim 1, characterized by, The length of the downhole temperature reducing device for oilfield drilling using chemical reaction is 9.8 m.

3. The downhole temperature reducing device for oil field drilling using chemical reaction according to claim 1, characterized by, The buckle type of the downhole temperature reducing device for oilfield drilling using chemical reaction is 410*411, the outer diameter is 184.2 mm, and the inner diameter is 57.2 mm.

4. The downhole temperature reducing device for oil field drilling using chemical reaction according to claim 1, characterized by, The thickness of the inner wall (8) of the downhole temperature reducing device for oilfield drilling using chemical reaction is 6 mm.

5. The downhole temperature reducing device for oil field drilling using chemical reaction according to claim 1, characterized by The total length of the high pressure cavity (2) and the medicine cavity (5) of the downhole temperature reducing device for oilfield drilling using chemical reaction is 8.8 m.

6. The downhole temperature reducing device for oil field drilling using chemical reaction according to claim 1, characterized by The oil field drilling downhole temperature reducing device using chemical reaction has high pressure cavity (2) and medicine cavity (5) volume of 0.2m 3 Wherein the maximum volume of medicine cavity (5) is 0.15m 3 .

7. The downhole temperature reducing device for oil field drilling using chemical reaction according to claim 1, characterized by The temperature sensor controller (3) and the medicine outlet switch are connected by an internal connecting line, the temperature sensor controller (3) controls the state of the medicine outlet switch according to the set temperature, and the temperature sensor controller (3) and the switch are powered by a self-contained battery.

8. The downhole temperature reducing device for oil field drilling using chemical reaction according to claim 1, characterized by The downhole temperature reducing device for oilfield drilling using chemical reaction can store medicine, which is ammonium chloride, ammonium nitrate or potassium nitrate.

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