Rotational viscometer suitable for different gas solubility and temperature and pressure and its use method

Abstract

The present invention relates to the field of oil and gas drilling, and in particular to a rotational viscometer suitable for different gas solubilities and temperatures and pressures and a method for using the same. The technical solution is: a rotor is installed in the inner cavity of a rotational viscosity measuring kettle, a suspension is installed above the rotor, the upper end of the suspension is connected to a return spring and an induction magnet, and a magnetic sensor is provided above the induction magnet; a bottom transmission magnet is provided at the bottom, a water bath cooling pipeline and a heating pipeline are provided on the outside, a high-pressure pipeline connection port is installed on the upper side, and the high-pressure pipeline connection port is connected to an air pump and a hydraulic oil storage tank through a high-pressure gas pipeline. The beneficial effect is: the present invention delivers high-pressure contaminated gas to the inner cavity of the rotational viscosity measuring kettle, thereby melting a target amount of contaminated gas into the liquid sample, and then drives the drilling fluid sample to rotate through the rotor, driving the suspension and the induction magnet to rotate; the rotational viscosity parameters of the drilling fluid are measured under specific temperature and pressure conditions and certain gas solubility conditions.

Description

Technical Field

[0001] The invention relates to the field of oil and gas drilling, and in particular to a rotational viscometer suitable for different gas solubilities and temperatures and pressures and a use method thereof. Background Art

[0002] With the continuous expansion of the scale of oil and gas resource exploration and development in my country, the continuous improvement of drilling technology and process level, more and more deepwater and ultra-deepwater wells are rapidly appearing in various exploration blocks; and with the increase of water depth, the probability of encountering abnormal formation pressure increases, and the difficulty of pressure control during drilling increases significantly. When overflow occurs, the solubility of gas in the drilling fluid will change, and it is difficult to detect the rotational viscosity of drilling fluids with different gas solubilities, and the rotational viscosity of drilling fluids cannot be changed in time; moreover, drilling fluids are often contaminated by gases such as carbon dioxide and hydrogen sulfide released by the formation in the high-temperature and high-pressure sections of deep wells, resulting in changes in the properties and rheology of the drilling fluid. At present, there is no relevant equipment that can measure how the rheology of drilling fluids contaminated by formation gas changes in the high-temperature and high-pressure sections.

[0003] Under overflow conditions, it is very important to control the bottom hole pressure. However, controlling the rotational viscosity of the drilling fluid is extremely important for controlling the bottom hole pressure. However, the overflow condition has different pressure and temperature conditions at different well depths, and the solubility of gas in the drilling fluid is different, which makes it impossible to accurately predict the rotational viscosity of the drilling fluid, resulting in the inability to accurately calculate the bottom hole circulation pressure loss, and thus the inability to accurately control the bottom hole pressure.

[0004] The Chinese utility model patent number is CN200520048234.X, and the patent name is "High-temperature and High-pressure Rotational Viscometer". It is mainly used for measuring the viscosity of viscous liquids such as coal-oil slurry, heavy oil slurry and asphalt during high-pressure heating in the coal chemical and petrochemical fields. The viscometer mainly consists of a pressure system, a heating system, a viscosity measurement system and a magnetic stirring system. It provides a viscosity measurement technology under high temperature and high pressure, but it cannot detect the rotational viscosity of drilling fluids with different gas solubility, nor can it change the rotational viscosity of drilling fluids in time, and cannot meet the requirements of drilling in abnormal formations. Summary of the invention

[0005] The purpose of the present invention is to address the above-mentioned defects in the prior art and provide a rotational viscometer and a method of use suitable for different gas solubilities and temperatures and pressures, so as to measure the rotational viscosity parameters of the drilling fluid under specific temperature and pressure conditions and certain contaminated gas solubility conditions, and provide a theoretical basis for adjusting the rotational viscosity parameters of the drilling fluid under actual working conditions.

[0006] The present invention mentions a rotational viscometer suitable for different gas solubilities and temperatures and pressures, and its technical solution is: including a computer, a rotational viscosity measuring kettle, which also includes a refrigerator, a bottom transmission magnet, a chain, a drive motor, a speed control relay, a heater, a drainage gas collecting device, a waste liquid storage tank, a gas outlet, an upper high-pressure stainless steel protective shell, a magnetic sensor, an induction magnet, a return spring, a suspension connecting rod, a middle high-pressure protective shell, a high-pressure pipeline connection port, a high-pressure gas inlet, a suspension, a lower high-pressure protective shell, a rotor, a water bath cooling pipeline, a heating pipeline, a high-pressure air pump, a hydraulic oil storage tank, and an air compressor. The lower high-pressure protective shell is installed on the outside of the rotational viscosity measuring kettle, the middle high-pressure protective shell is provided on the upper side of the rotational viscosity measuring kettle, and the upper part of the middle high-pressure protective shell is provided with an upper high-pressure stainless steel protective shell. A rotor is installed in the inner cavity of the rotational viscosity measuring kettle, and a suspension is installed above the rotor. The upper end of the suspension is suspended by a suspension. A vertical connecting rod connects the return spring and the induction magnet, and a magnetic sensor is arranged above the induction magnet; a bottom transmission magnet is arranged at the bottom of the rotational viscosity measuring kettle, and the lower end of the bottom transmission magnet is connected to the drive motor through a chain, and the drive motor is connected to the control speed relay and the computer through a control line; a water bath cooling pipeline and a heating pipeline are arranged on the outside of the rotational viscosity measuring kettle, the water bath cooling pipeline is connected to the refrigerator through a pipeline, and the computer is connected to the refrigerator through a control line; the heating pipeline is connected to the heater through a pipeline, and the computer is connected to the heater through a control line; a high-pressure pipeline connection port and a gas discharge port are installed on the upper side of the rotational viscosity measuring kettle, the high-pressure pipeline connection port is connected to the high-pressure air pump and the hydraulic oil storage tank through a high-pressure gas pipeline, one end of the high-pressure air pump is connected to the air compressor through a high-pressure pipeline, and the gas discharge port is connected to the waste liquid storage tank and the drainage gas collecting device through a pipeline, and a plurality of high-pressure gas inlets are arranged on the high-pressure pipeline in the rotational viscosity measuring kettle.

[0007] Preferably, the above-mentioned rotor is mounted on a rotor positioner, and a rotor positioning bearing is installed on the top of the rotor positioner, a rotor lower induction magnet is installed on the lower part of the rotor, and a rotor magnet bearing is installed on the rotor positioner below the rotor.

[0008] Preferably, the upper end of the above-mentioned suspension connecting rod is connected to the magnet connecting rod through a connecting buckle, and the induction magnet is installed on the outside of the magnet connecting rod.

[0009] Preferably, a return spring is installed at the bottom of the above-mentioned induction magnet, a spring top fixing buckle is provided above the return spring, a spring bottom fixing buckle is provided below the return spring, and a magnet connecting rod fixing plate is installed on the upper part of the magnet connecting rod.

[0010] Preferably, a temperature sensor and a pressure sensor are installed on the lower side of the above-mentioned rotational viscosity measuring kettle.

[0011] Preferably, the outer wall surface of the above-mentioned rotor is provided with threads, and a small hole is provided at the bottom of the rotor.

[0012] Preferably, a pressure relief valve is installed on the pipeline between the gas outlet and the waste liquid storage tank.

[0013] Preferably, an air compressor pressure gauge is installed on the above-mentioned air compressor, and an air pump pressure gauge is installed on the high-pressure air pump.

[0014] The method for using the rotational viscometer applicable to different gas solubility and temperature and pressure mentioned in the present invention comprises the following process:

[0015] First, the air compressor starts working and pumps gas into the high-pressure air pump. When the air compressor pressure gauge shows 0.8MPa, it means the pressure meets the standard. When the air pump pressure gauge shows 100psi, it means the pressure meets the standard. Then it continuously delivers high-pressure gas to the inner cavity of the rotary viscosity measuring kettle. A circular high-pressure pipeline is provided above the inner cavity of the rotary viscosity measuring kettle. The high-pressure gas is delivered into the rotary viscosity measuring kettle around the suspended connecting rod, so that the target amount of gas is melted into the liquid sample and the pressure in the rotary viscosity measuring kettle is increased. After the set requirements are met, the high-pressure air pump starts the hydraulic oil pressurization and delivers the hydraulic oil from the hydraulic oil storage tank to the rotary viscosity measuring kettle for further pressurization. The pressure sensor accurately detects the pressure in the rotary viscosity measuring kettle and displays it on the computer.

[0016] In the second step, when a high-temperature test is to be performed, the computer controls the heater to make the heating pipeline heat the tank body of the rotary viscosity measuring kettle. When a low-temperature test is required, the computer controls the refrigerator to start. Ethylene glycol is used as a circulating cooling material in the refrigerator. It circulates in the water bath cooling pipeline to cool the tank body. After the pressure and temperature reach the set requirements, the computer controls the drive motor to start, and then drives the bottom transmission magnet to rotate through the chain. The rotation of the bottom transmission magnet drives the rotor to rotate and shear the drilling fluid sample. The high-speed rotation of the drilling fluid sample drives the suspension to rotate and drives the upper induction magnet to rotate together. The magnetic sensor senses the resistance of the suspension through the induction magnet, and then measures the rotational viscosity of the drilling fluid sample. After the experiment, the return spring returns the suspension connecting rod to its original position by plastic elastic force. The magnetic sensor measurement results are used to calculate the rheological parameters of the drilling fluid sample within the selected temperature and pressure range after a certain amount of gas is dissolved in the sample, providing a theoretical basis for the study of the rotational viscosity of the drilling fluid that incorporates gas in high-temperature and high-pressure wells.

[0017] The third step is to open the pressure relief valve after the experiment. A small amount of liquid will be carried into the waste liquid storage tank along with the gas. An electric piston will discharge the gas at the bottom of the waste liquid storage tank. The gas will then enter the drainage gas collection device for environmental protection treatment to prevent atmospheric pollution.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] The present invention can test the rotational viscosity of liquid under different temperature and pressure conditions and a certain contaminant gas solubility; high-pressure contaminant gas is delivered to the inner cavity of the rotational viscosity measurement kettle through an air compressor and a high-pressure air pump, and the high-pressure contaminant gas is delivered into the rotational viscosity measurement kettle, so that a target amount of contaminant gas is melted into the liquid sample, and the pressure in the rotational viscosity measurement kettle is increased. After reaching the set requirements, the high-pressure air pump starts the hydraulic oil pressurization, and the hydraulic oil is delivered from the hydraulic oil storage tank to the rotational viscosity measurement kettle for continued pressurization, and then the subsequent rotational viscosity measurement is performed by controlling the temperature;

[0020] The present invention drives the rotor to rotate through the bottom transmission magnet, and the rotor drives the drilling fluid sample with a certain viscosity in the rotary viscosity measuring kettle to rotate. The rotating drilling fluid sample drives the suspension to rotate through the effect of viscosity, and drives the induction magnet on the top connected to the suspension to rotate together; at the same time, the installed return spring is subjected to a reverse torsion driven by the rotation of the induction magnet on the top, and when the forces in two directions received by the spring reach a balance, the induction magnet rotates through a certain angle, and the greater the viscosity of the drilling fluid sample, the greater the angle of rotation of the induction magnet driven by the viscosity; the angle of rotation is the Dial reading, so as to obtain the shear stress of the drilling fluid sample, and the shear stress is ≈ 0.5*Dial reading.

[0021] The present invention realizes the measurement of the rotational viscosity parameters of the drilling fluid under specific temperature and pressure conditions and certain contaminated gas solubility conditions, and provides a theoretical basis for adjusting the rotational viscosity parameters of the drilling fluid under actual working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0023] Figure 2 It is a schematic diagram of the principle of the suspension and induction magnet parts;

[0024] Figure 3 It is a schematic diagram of the structure of the rotor;

[0025] Figure 4 This is the shear stress curve of X oilfield drilling fluid with temperature and pressure when the carbon dioxide solubility is 70g / L;

[0026] Figure 5 This is the shear stress curve of X oilfield drilling fluid with temperature and pressure when the solubility of hydrogen sulfide is 185g / L;

[0027] In the figure above: refrigerator 1, bottom transmission magnet 2, chain 3, drive motor 4, speed control relay 5, computer 6, heater 7, drainage gas collector 8, waste liquid storage tank 9, pressure relief valve 10, gas outlet 11, upper high-pressure stainless steel protective shell 12, magnetic sensor 13, magnet connecting rod 14, induction magnet 15, return spring 16, upper spring protection bearing 17, connecting buckle 18, hanging connecting rod 19, middle high-pressure protective shell 20, high-pressure pipeline connection port 21, high-pressure gas inlet 22, hanging 23, lower high-pressure protective shell 24, rotor 25, water bath cooling pipeline 26, temperature sensor 27, pressure sensor 28, rotor magnet bearing 29, rotor lower induction magnet 30, rotor positioner 31, rotor positioning bearing 32, heating pipeline 33, air pump pressure gauge 34, high-pressure air pump 35, hydraulic oil storage tank 36, air compressor 37, air compressor pressure gauge 38, rotation viscosity measuring kettle 39, fixing plate 2.1, spring top fixing buckle 2.2, spring bottom fixing buckle 2.3, thread 25.1, small hole 25.2. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0029] Example 1, reference Figure 1-Figure 3The present invention relates to a rotational viscometer suitable for different gas solubility and temperature and pressure, comprising a refrigerator 1, a bottom transmission magnet 2, a chain 3, a drive motor 4, a speed control relay 5, a computer 6, a heater 7, a drainage gas collecting device 8, a waste liquid storage tank 9, a gas outlet 11, an upper high-pressure stainless steel protective shell 12, a magnetic sensor 13, an induction magnet 15, a return spring 16, a suspension connecting rod 19, a middle high-pressure protective shell 20, a high-pressure pipeline connection port 21, a high-pressure gas inlet 22, a suspension 23, and a lower high-pressure protective shell 24, rotor 25, water bath cooling pipeline 26, heating pipeline 33, high-pressure air pump 35, hydraulic oil storage tank 36, air compressor 37, rotation viscosity measuring kettle 39, the rotation viscosity measuring kettle 39 is provided with a lower high-pressure protective shell 24 on the outside, the rotation viscosity measuring kettle 39 is provided with a middle high-pressure protective shell 20 on the upper side, and an upper high-pressure stainless steel protective shell 12 is provided on the upper part of the middle high-pressure protective shell 20, the rotor 25 is installed in the inner cavity of the rotation viscosity measuring kettle 39, the suspension 23 is installed above the rotor 25, and the upper end of the suspension 23 is connected to the suspension by the suspension The connecting rod 19 connects the return spring 16 and the induction magnet 15, and a magnetic sensor 13 is arranged above the induction magnet 15; a bottom transmission magnet 2 is arranged at the bottom of the rotational viscosity measuring kettle 39, and the lower end of the bottom transmission magnet 2 is connected to the drive motor 4 through a chain 3, and the drive motor 4 is connected to the speed control relay 5 and the computer 6 through a control line; a water bath cooling pipeline 26 and a heating pipeline 33 are arranged on the outside of the rotational viscosity measuring kettle 39, and the water bath cooling pipeline 26 is connected to the refrigerator 1 through a pipeline, and the computer 6 is connected to the refrigerator 1 through a control line; The heating pipeline 33 is connected to the heater 7 through a pipeline, and the computer 6 is connected to the heater 7 through a control line. A high-pressure pipeline connection port 21 and a gas exhaust port 11 are installed on the upper side of the rotational viscosity measuring kettle 39. The high-pressure pipeline connection port 21 is connected to the high-pressure air pump 35 and the hydraulic oil storage tank 36 through a high-pressure gas pipeline. One end of the high-pressure air pump 35 is connected to the air compressor 37 through a high-pressure pipeline. The gas exhaust port 11 is connected to the waste liquid storage tank 9 and the drainage gas collecting device 8 through a pipeline. A plurality of high-pressure gas inlets 22 are provided on the high-pressure pipeline in the rotational viscosity measuring kettle 39.

[0030] The rotor 25 is mounted on a rotor positioner 31 , and a rotor positioning bearing 32 is mounted on the top of the rotor positioner 31 . A rotor lower induction magnet 30 is mounted on the lower part of the rotor 25 , and a rotor magnet bearing 29 is mounted on the rotor positioner 31 below the rotor 25 .

[0031] The upper end of the above-mentioned suspension connecting rod 19 is connected to the magnet connecting rod 14 through a connecting buckle 18, and the induction magnet 15 is installed outside the magnet connecting rod 14.

[0032] A return spring 16 is installed at the bottom of the above-mentioned induction magnet 15, an upper spring protection bearing 17 is installed at the bottom of the induction magnet 15, a spring top fixing buckle 2.2 is provided above the return spring 16, a spring bottom fixing buckle 2.3 is provided below the return spring 16, and a magnet connecting rod fixing plate 2.1 is installed on the upper part of the magnet connecting rod 14.

[0033] A temperature sensor 27 and a pressure sensor 28 are installed on the lower side of the above-mentioned rotational viscosity measuring kettle 39 .

[0034] The outer wall surface of the rotor 25 is provided with a thread 25.1, and a small hole 25.2 is provided at the bottom of the rotor 25. The thread 25.1 is used to prevent the drilling fluid sample from agglomerating during high-speed stirring. The small hole 25.2 at the bottom of the rotor 25 can ensure that the drilling fluid sample fully wraps the entire rotor 25.

[0035] A pressure relief valve 10 is installed on the pipeline between the gas outlet 11 and the waste liquid storage tank 9 .

[0036] An air compressor pressure gauge 38 is installed on the air compressor 37 , and an air pump pressure gauge 34 is installed on the high-pressure air pump 35 .

[0037] The method for using the rotational viscometer applicable to different gas solubility and temperature and pressure mentioned in the present invention comprises the following process:

[0038] First, the air compressor 37 starts to work and pumps carbon dioxide gas into the high-pressure air pump 35. When the air compressor pressure gauge 38 shows that the pressure reaches 0.8MPa, it means that the pressure meets the standard. When the air pump pressure gauge 34 reaches 100psi, it means that the pressure meets the standard, and then the high-pressure carbon dioxide gas is continuously transported to the inner cavity of the rotational viscosity measurement kettle 39. A circular high-pressure pipeline is provided above the inner cavity of the rotational viscosity measurement kettle 39. The high-pressure carbon dioxide gas is transported into the rotational viscosity measurement kettle 39 around the hanging connecting rod 19, so that the target amount of carbon dioxide gas is melted into the liquid sample and the pressure in the rotational viscosity measurement kettle 39 is increased. After the set requirements are met, the high-pressure air pump 35 starts the hydraulic oil pressurization and transports the hydraulic oil from the hydraulic oil storage tank 36 to the rotational viscosity measurement kettle 39 for continued pressurization. The pressure sensor 28 accurately detects the pressure in the rotational viscosity measurement kettle 39 and displays it on the computer 6;

[0039] In the second step, when a high temperature test is to be performed, the computer 6 controls the heater 7 to make the heating pipeline 33 heat the tank body of the rotary viscosity measuring kettle 39. When a low temperature test is to be performed, the computer 6 controls the refrigerator 1 to start. Ethylene glycol is used as a circulating cooling material in the refrigerator 1. It circulates in the water bath cooling pipeline 26 to cool the tank body. After the pressure and temperature reach the set requirements, the computer 6 controls the drive motor 4 to start, and then drives the bottom transmission magnet 2 to rotate through the chain 3. The rotation of the bottom transmission magnet 2 drives the rotor 25 to rotate and shear the drilling fluid sample. The drilling fluid sample The high-speed rotation of the sample drives the suspension 23 to rotate and drives the upper induction magnet 15 to rotate together. The magnetic sensor 13 senses the resistance of the suspension 23 through the induction magnet 15, and then measures the rotational viscosity of the drilling fluid sample. After the experiment, the return spring 16 returns the suspension connecting rod 19 to its original position by plastic elastic force. The measurement result of the magnetic sensor 13 is calculated by the computer 6 to calculate the rheological parameters of the drilling fluid sample within the selected temperature and pressure range after a certain amount of gas is dissolved in the sample, which provides a theoretical basis for the study of the rotational viscosity of the drilling fluid that incorporates carbon dioxide gas in high-temperature and high-pressure wells;

[0040] The third step is to open the pressure relief valve 10 after the experiment, and a small amount of liquid is brought into the waste liquid storage tank 9 along with the carbon dioxide gas. An electric piston is provided at the bottom of the waste liquid storage tank 9 to discharge the carbon dioxide gas, and the gas then enters the drainage gas collecting device 8 for environmental protection treatment to prevent air pollution.

[0041] The experimental results are as follows:

[0042] The following experiment was conducted using the rotational viscometer of the present invention. The experimental data of different gas contaminations under high temperature and high pressure conditions were carried out using the X oil field drilling fluid as the test sample. The pressure of 120 MPa was used as an example to show that the contaminant gas was carbon dioxide. Figure 4 The drilling fluid is contaminated with carbon dioxide and has a solubility of 70g / L. After the gas is injected, it starts to be heated and pressurized. The figure clearly shows the change in the properties of the drilling fluid when it is contaminated with carbon dioxide gas, which provides a certain theoretical basis for adjusting its composition during drilling work.

[0043] Example 2, the method for using the rotational viscometer applicable to different gas solubility and temperature and pressure mentioned in the present invention is different from Example 1 in that it includes the following process:

[0044] First, the air compressor 37 starts to work and pumps hydrogen sulfide gas into the high-pressure air pump 35. When the air compressor pressure gauge 38 shows that the pressure reaches 0.8MPa, it means that the pressure meets the standard. When the air pump pressure gauge 34 reaches 100psi, it means that the pressure meets the standard. Then, the high-pressure hydrogen sulfide gas is continuously transported to the inner cavity of the rotary viscosity measuring kettle 39. A circular high-pressure pipeline is provided above the inner cavity of the rotary viscosity measuring kettle 39. The high-pressure hydrogen sulfide gas is transported into the rotary viscosity measuring kettle 39 around the hanging connecting rod 19, so that the target amount of hydrogen sulfide gas is melted into the liquid sample and the pressure in the rotary viscosity measuring kettle 39 is increased. After the set requirements are met, the high-pressure air pump 35 starts the hydraulic oil pressurization and transports the hydraulic oil from the hydraulic oil storage tank 36 to the rotary viscosity measuring kettle 39 for continued pressurization. The pressure sensor 28 accurately detects the pressure in the rotary viscosity measuring kettle 39 and displays it on the computer 6.

[0045] In the second step, when a high temperature test is to be performed, the computer 6 controls the heater 7 to make the heating pipeline 33 heat the tank body of the rotary viscosity measuring kettle 39. When a low temperature test is to be performed, the computer 6 controls the refrigerator 1 to start. Ethylene glycol is used as a circulating cooling material in the refrigerator 1. It circulates in the water bath cooling pipeline 26 to cool the tank body. After the pressure and temperature reach the set requirements, the computer 6 controls the drive motor 4 to start, and then drives the bottom transmission magnet 2 to rotate through the chain 3. The rotation of the bottom transmission magnet 2 drives the rotor 25 to rotate and shear the drilling fluid sample. The drilling fluid sample The high-speed rotation of the sample drives the suspension 23 to rotate and drives the upper induction magnet 15 to rotate together. The magnetic sensor 13 senses the resistance of the suspension 23 through the induction magnet 15, and then measures the rotational viscosity of the drilling fluid sample. After the experiment, the return spring 16 returns the suspension connecting rod 19 to its original position by plastic elastic force. The measurement result of the magnetic sensor 13 is calculated by the computer 6 to calculate the rheological parameters of the drilling fluid sample within the selected temperature and pressure range after a certain amount of gas is dissolved in the sample, which provides a theoretical basis for the study of the rotational viscosity of the drilling fluid in which hydrogen sulfide gas is integrated in high-temperature and high-pressure wells;

[0046] The third step is to open the pressure relief valve 10 after the experiment, and a small amount of liquid is brought into the waste liquid storage tank 9 along with the hydrogen sulfide gas. An electric piston is provided at the bottom of the waste liquid storage tank 9 to discharge the hydrogen sulfide gas, and the gas then enters the drainage gas collecting device 8 for environmental protection treatment to prevent air pollution.

[0047] The experimental results are as follows:

[0048] The following experiment was conducted using the rotational viscometer of the present invention. The experimental data of different gas contaminations under high temperature and high pressure conditions were carried out using the X oil field drilling fluid as the test sample. The pressure of 120 MPa was used as an example to show that the contaminant gas was hydrogen sulfide. Figure 5The solubility of the drilling fluid contaminated by hydrogen sulfide is 185g / L, and heating and pressurization are started after the gas is injected. The figure clearly shows the change in the properties of the drilling fluid when it is contaminated by hydrogen sulfide gas, which provides a certain theoretical basis for adjusting its composition during drilling work.

[0049] The above are only some preferred embodiments of the present invention. Any person skilled in the art may modify the above technical solutions or modify them into equivalent technical solutions. Therefore, the corresponding simple modifications or equivalent transformations made according to the technical solutions of the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A rotational viscometer suitable for different gas solubilities and temperatures and pressures, comprising a computer (6) and a rotational viscosity measuring kettle (39), characterized in that: It also includes a refrigerator (1), a bottom transmission magnet (2), a chain (3), a drive motor (4), a speed control relay (5), a heater (7), a drainage gas collection device (8), a waste liquid storage tank (9), a gas outlet (11), an upper high-pressure stainless steel protective shell (12), a magnetic sensor (13), an induction magnet (15), a return spring (16), a suspension connecting rod (19), a middle high-pressure protective shell (20), a high-pressure pipeline connection port (21), a high-pressure gas inlet port (22), a suspension (23), a lower high-pressure protective shell (24), a rotor (25), a water bath cooling pipeline (26), A heating pipeline (33), a high-pressure air pump (35), a hydraulic oil storage tank (36), and an air compressor (37); a lower high-pressure protective shell (24) is installed on the outside of the rotary viscosity measuring kettle (39); a middle high-pressure protective shell (20) is installed on the upper side of the rotary viscosity measuring kettle (39); an upper high-pressure stainless steel protective shell (12) is installed on the upper part of the middle high-pressure protective shell (20); a rotor (25) is installed in the inner cavity of the rotary viscosity measuring kettle (39); a suspension (23) is installed above the rotor (25); and the upper end of the suspension (23) is connected to a return spring (16) and an induction magnet (12) via a suspension connecting rod (19). 5), a magnetic sensor (13) is provided above the induction magnet (15); a bottom transmission magnet (2) is provided at the bottom of the rotational viscosity measuring kettle (39), the lower end of the bottom transmission magnet (2) is connected to the drive motor (4) through a chain (3), and the drive motor (4) is connected to the speed control relay (5) and the computer (6) through a control line; a water bath cooling pipeline (26) and a heating pipeline (33) are provided on the outside of the rotational viscosity measuring kettle (39), the water bath cooling pipeline (26) is connected to the refrigerator (1) through a pipeline, and the computer (6) is connected to the refrigerator (1) through a control line; the heating pipeline (33) The heater (7) is connected via a pipeline, and the computer (6) is connected to the heater (7) via a control line. A high-pressure pipeline connection port (21) and a gas outlet (11) are installed on the upper side of the rotational viscosity measuring kettle (39). The high-pressure pipeline connection port (21) is connected to a high-pressure air pump (35) and a hydraulic oil storage tank (36) via a high-pressure gas pipeline. One end of the high-pressure air pump (35) is connected to an air compressor (37) via a high-pressure pipeline. The gas outlet (11) is connected to a waste liquid storage tank (9) and a drainage gas collecting device (8) via a pipeline. A plurality of high-pressure gas inlets (22) are provided on the high-pressure pipeline in the rotational viscosity measuring kettle (39).

2. The rotational viscometer suitable for different gas solubility and temperature and pressure according to claim 1, characterized in that: The rotor (25) is mounted on a rotor positioner (31), and a rotor positioning bearing (32) is mounted on the top of the rotor positioner (31). A rotor lower induction magnet (30) is mounted on the lower part of the rotor (25), and a rotor magnet bearing (29) is mounted on the rotor positioner (31) below the rotor (25).

3. The rotational viscometer suitable for different gas solubility and temperature and pressure according to claim 2 is characterized in that: The upper end of the suspended connecting rod (19) is connected to the magnet connecting rod (14) via a connecting buckle (18), and an induction magnet (15) is installed outside the magnet connecting rod (14).

4. The rotational viscometer suitable for different gas solubility and temperature and pressure according to claim 3 is characterized in that: A return spring (16) is installed at the bottom of the induction magnet (15), a spring top fixing buckle (2.2) is provided above the return spring (16), a spring bottom fixing buckle (2.3) is provided below the return spring (16), and a magnet connecting rod fixing plate (2.1) is installed at the top of the magnet connecting rod (14).

5. The rotational viscometer suitable for different gas solubility and temperature and pressure according to claim 4 is characterized in that: A temperature sensor (27) and a pressure sensor (28) are installed on the lower side of the rotational viscosity measuring kettle (39).

6. The rotational viscometer suitable for different gas solubility and temperature and pressure according to claim 5, characterized in that: The outer wall surface of the rotor (25) is provided with threads, and a small hole is provided at the bottom of the rotor (25).

7. The rotational viscometer suitable for different gas solubility and temperature and pressure according to claim 6, characterized in that: A pressure relief valve (10) is installed on the pipeline between the gas outlet (11) and the waste liquid storage tank (9).

8. The rotational viscometer suitable for different gas solubility and temperature and pressure according to claim 7 is characterized in that: An air compressor pressure gauge (38) is installed on the air compressor (37), and an air pump pressure gauge (34) is installed on the high-pressure air pump (35).

9. The method for using the rotational viscometer applicable to different gas solubility and temperature and pressure according to claim 8, characterized in that: The process includes the following: First, the air compressor (37) starts working and pumps gas into the high-pressure air pump (35). When the air compressor pressure gauge (38) shows that the pressure reaches 0.8 MPa, it means that the pressure meets the standard. When the air pump pressure gauge (34) reaches 100 psi, it means that the pressure meets the standard. Then, the high-pressure gas is continuously delivered to the inner cavity of the rotary viscosity measuring kettle (39). A circular high-pressure pipeline is provided above the inner cavity of the rotary viscosity measuring kettle (39), surrounding the hanging connecting rod (19), and the high-pressure gas is delivered into the rotary viscosity measuring kettle (39), so that the target amount of gas is melted into the liquid sample and the pressure in the rotary viscosity measuring kettle (39) is increased. After the set requirements are met, the high-pressure air pump (35) starts the hydraulic oil pressurization and delivers the hydraulic oil from the hydraulic oil storage tank (36) to the rotary viscosity measuring kettle (39) for continued pressurization. The pressure sensor (28) accurately detects the pressure in the rotary viscosity measuring kettle (39) and displays it on the computer (6); In the second step, when a high temperature test is to be performed, the computer (6) controls the heater (7) to make the heating pipeline (33) heat the tank body of the rotary viscosity measuring kettle (39). When a low temperature test is to be performed, the computer (6) controls the refrigerator (1) to start. Ethylene glycol is used as a circulating cooling material in the refrigerator (1). It circulates in the water bath cooling pipeline (26) to cool the tank body. After the pressure and temperature reach the set requirements, the computer (6) controls the drive motor (4) to start, and then drives the bottom transmission magnet (2) to rotate through the chain (3). The rotation of the bottom transmission magnet (2) drives the rotor (25) to rotate and shear the drilling fluid. The drilling fluid sample rotates at a high speed to drive the suspension (23) to rotate and drive the upper induction magnet (15) to rotate together. The magnetic sensor (13) senses the resistance of the suspension (23) through the induction magnet (15), and then measures the rotational viscosity of the drilling fluid sample. After the experiment is over, the return spring (16) returns the suspension connecting rod (19) to its original position by plastic elastic force. The measurement result of the magnetic sensor (13) is calculated by a computer (6) to calculate the rheological parameters of the drilling fluid sample within a selected temperature and pressure range after a certain amount of gas is dissolved in the sample, thereby providing a theoretical basis for the study of the rotational viscosity of the drilling fluid dissolved with gas in a high temperature and high pressure well. The third step is to open the pressure relief valve (10) after the experiment is over, and a small amount of liquid is carried into the waste liquid storage tank (9) along with the gas. An electric piston is provided at the bottom of the waste liquid storage tank (9) to discharge the gas, and the gas then enters the drainage gas collection device (8) for environmental protection treatment to prevent air pollution.

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