Liquid level measuring device for petroleum gathering and transportation tank

Abstract

The utility model discloses a liquid level measuring device for a petroleum gathering and transportation tank, which is characterized in that a measuring table is arranged above a tank body, and a power supply and a motor driver are arranged on the upper surface of the measuring table; an explosion-proof motor, a fixing support and a force sensor are fixed to the top of an inner cavity of the tank body, the explosion-proof motor is in driving connection with the wire spool, a rotating wheel and an encoder of the rotating wheel are arranged on the lower portion of the fixing support, and a fixed pulley is hooked below the force sensor. The steel wire is led out of the wire spool and sequentially bypasses the rotating wheel and the fixed pulley, and the movable end of the steel wire is connected with a solid ball. The device further comprises a controller, the controller is in signal connection with the motor driver, the encoder and the force sensor, and the motor driver is in control connection with the explosion-proof motor. The utility model belongs to the technical field of oil-water measurement, and through the combination of the sensor and the encoder, high-precision liquid level measurement can be provided, and full-automatic control of liquid level measurement is realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of oil-water measurement, and relates to a liquid level measuring device for an oil gathering and transportation tank. Background Art

[0002] Accurately measuring the oil-water interface in crude oil storage tanks is a basic requirement for the oil extraction and processing process. After preliminary investigation, many operating areas still use the traditional manual ruler method to measure the height of the oil-water liquid level. The manual ruler measurement relies on the surveyor to climb to the top of the crude oil storage tank, use a metric tape measure with a heavy hammer or a ruler with a scale to measure, and find the interface by manually feeling the force change when the heavy hammer passes through the oil-water junction, and then manually record the readings, calculate the oil-water level height, and obtain the oil-water interface position. However, when measuring, the tester needs to climb to the top of the tank of more than ten meters or even dozens of meters to operate, which is labor-intensive and poses a great threat to the personal safety of the tester; and the measurement timeliness is poor, and the measurement results cannot be fed back to the management department in time; at the same time, the level measurement error varies from person to person and has poor consistency. Utility Model Content

[0003] The utility model aims to provide a liquid level measuring device for an oil gathering tank, so as to solve the problem that the oil-water measuring structure design of the existing oil gathering tank is unscientific and the oil level and water level layer height in the large tank body cannot be accurately measured.

[0004] The technical scheme adopted by the utility model is that the liquid level measuring device for oil gathering and transportation tank is provided, a measuring platform is arranged above the outside of the tank body, a power supply and a motor driver are installed on the upper surface of the measuring platform; an explosion-proof motor, a fixed bracket and a force sensor are respectively fixed on the top of the inner cavity of the tank body, the output shaft of the explosion-proof motor is connected with the winding drum drive, a rotating wheel and an encoder thereof are arranged at the lower part of the fixed bracket, and a fixed pulley is hooked below the force sensor; the fixed end of the steel wire is led out from the winding drum, passes around the rotating wheel and the fixed pulley in turn, and the movable end of the steel wire is connected with a solid ball; and a controller is also included, the controller is connected with the motor driver, the encoder and the force sensor signal, and the motor driver is connected with the explosion-proof motor control.

[0005] The liquid level measuring device for oil gathering and transportation tanks of the utility model is also characterized in that:

[0006] The force sensor is used to collect the tensile force value of the solid ball.

[0007] The motor driver, the explosion-proof motor and the winding drum rotate in conjunction with each other.

[0008] The encoder is used to output the actual rotation speed of the rotating wheel, that is, the lifting speed of the steel wire.

[0009] The pulley, the rotating wheel where the encoder is located, and the winding disk together form a movable pulley group.

[0010] The beneficial effect of the utility model is that it is used to detect large oil gathering tanks / sedimentation tanks. Through the combination of sensors and encoders, it can provide high-precision liquid level measurement to ensure the reliability and accuracy of data. At the same time, it integrates explosion-proof motors and winding reels to achieve fully automatic control of liquid level measurement, reduce manual operations, and improve efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the structure of the liquid level measuring device of the utility model;

[0012] Figure 2 This is a top view of the structure of the liquid level measuring device of the utility model;

[0013] Figure 3 It is a structural side view of the liquid level measuring device of the utility model.

[0014] In the figure, 1. solid ball; 2. steel wire; 3. fixed pulley; 4. force sensor; 5. encoder; 6. fixed bracket; 7. power supply; 8. motor driver; 9. explosion-proof motor; 10. winding drum; 11. controller; 12. tank body; 13. measuring table. DETAILED DESCRIPTION

[0015] Reference Figure 1 , Figure 2 , Figure 3 The structure of the liquid level measuring device of the utility model is that a measuring platform 13 is arranged above the outside of the tank body 12, and a power supply 7 and a motor driver 8 are installed on the upper surface of the measuring platform 13; an explosion-proof motor 9, a fixed bracket 6 and a force sensor 4 are fixedly installed side by side on the top of the inner cavity of the tank body 12, the output shaft of the explosion-proof motor 9 is connected to the winding drum 10, a rotating wheel and an encoder 5 are arranged at the lower part of the fixed bracket 6, and a fixed pulley 3 is hooked under the force sensor 4; the fixed end of the steel wire 2 is led out from the winding drum 10, and passes around the rotating wheel and the fixed pulley 3 in turn, and the movable end of the steel wire 2 is connected to the solid ball 1; it also includes a controller 11, the controller 11 is connected to the motor driver 8 and the encoder 5 signals, and the motor driver 8 is connected to the explosion-proof motor 9 control connection.

[0016] The force sensor 4 is used to collect the pulling force value of the solid ball 1. The solid ball 1 can be a metal ball. The encoder 5 is used to output the actual rotation speed of the rotating wheel, that is, the lifting speed of the steel wire 2.

[0017] The pulley 3, the rotating wheel where the encoder 5 is located, and the winding disk 10 together form a movable pulley group.

[0018] The motor driver 8, the explosion-proof motor 9 and the winding drum 10 rotate in conjunction with each other, that is, the release speed and the take-up speed of the steel wire 2 are controlled.

[0019] The controller 11 is used to coordinate the operation of the foregoing various electrical components, collect relevant data, and accurately obtain the layered heights of the oil surface and the water surface in the tank body 12 by adopting the following operation process.

[0020] The function of the measuring platform 13 is to place the power supply 7 and the motor driver 8.

[0021] The working principle of the liquid level measuring device of the present utility model is as follows:

[0022] It is assumed that the liquid in the tank body 12 includes viscous oil in the upper layer and water in the lower layer, and there is still space between the oil surface and the top of the tank body 12, that is, there is still gas.

[0023] Before measurement, the solid ball 1 is sunk into the tank body 12 and stays on the bottom plate of the tank body 12;

[0024] 1) Start measurement. The controller 11 sends a start signal to the motor driver 8. The motor driver 8 controls the output shaft of the explosion-proof motor 9 to rotate at a constant speed, provides the pulling force T for the upward movement of the solid ball 1 and keeps the speed constant, and evenly retracts the steel wire 2 to evenly lift the solid ball 1 upward; the retracted length of the steel wire 2 is sensed by the rotation of the encoder 5, and the force sensor 4 measures in real time the sinking pulling force of the solid ball 1 on the fixed pulley 3. Based on the force principle of the fixed pulley 3, the actual downward pulling force F measured by the force sensor 4 at this time is F = 2T;

[0025] When the solid ball 1 rises evenly in the liquid in the tank body 12, the solid ball 1 will be subjected to the upward pulling force T provided by the explosion-proof motor 9, the gravity G of the solid ball 1, the buoyancy F provided by the liquid 浮 and the resistance F suffered by the spherical object when moving evenly in the liquid 阻 ; Since the solid ball 1 moves in a uniform straight line, it can be regarded as a state of force balance at this time, and the force expression of the solid ball 1 is obtained, as shown in formula (1):

[0026] T + F_buoyancy = G + F_resistance, (1)

[0027] Then the pulling force T provided by the explosion-proof motor 9 is:

[0028] T = G + F_resistance - F_buoyancy, (2)

[0029] From this, the actual downward pulling force F measured by the force sensor 4 is:

[0030] F = 2×(G + F 阻 - F 浮 ), (3)

[0031] The following conclusions are obtained from the formulas of Stokes' law and Archimedes' principle:

[0032] When the solid ball 1 is in water, the explosion-proof motor 9 applies the pulling force T 1and the force F measured by the sensor 4 1 As shown in formulas (4) and (5):

[0033]

[0034] R represents the radius of the solid sphere 1; η 水 represents the dynamic viscosity coefficient of water; ρ 水 the density of water; v represents the velocity of the solid sphere 1 moving in the liquid.

[0035] When the solid sphere 1 is in the heavy oil, the explosion-proof motor 9 applies a pulling force T 2 and the force F measured by the sensor 4 2 As shown in formulas (6) and (7):

[0036]

[0037] η 油 represents the oil viscosity coefficient; ρ 油 represents the density of water.

[0038] Since it is known that η 油 > η 水 and ρ 油 < ρ 水 , therefore, when the solid sphere 1 passes through the oil-water interface at a uniform speed, the force sensor 4 will measure a sudden increase in the pulling force, and the instantaneous change value is:[[]]

[0039]

[0040] Since the air resistance and buoyancy are too small to be negligible, when the solid sphere is in the air, T = mg. Therefore, when the solid sphere 1 breaks through the water surface, a second sudden change in the pulling force will be measured, and the second instantaneous change value is:[[]]

[0041]

[0042] It can be seen from formula (9) that to ensure accurate recording of the sudden change of the secondary force, the linear velocity v of the explosion-proof motor 9 should be adjusted according to the resistance coefficient and density of the heavy oil so that the following conditions are met:[[]]

[0043] That is

[0044] During the measurement process, the acquisition data obtained by the encoder 5 and the force sensor 4 corresponding to the time series are recorded in real time.[[]]

[0045] 2) According to the recorded acquisition data, calculate the result values of the water surface height and the oil-water interface height.[[]]

[0046] Since an encoder 5 is installed on the rotating wheel around which the steel wire 2 passes, it is only necessary to record the readings of the encoder 5 at the start and at the two times of force mutation, segment according to the force mutation situation, distinguish the oil surface and the water surface, and thus calculate the respective liquid level heights of the oil surface and the water surface.

[0047] The encoder 5 detects the angular displacement of the rotation of the rotating wheel and outputs a certain number of pulse signals. Each pulse represents a certain angular change of θ. By counting the number of pulses, the rotation angle is determined, and thus the distance lifted by the steel wire 2 is calculated. The specific calculation formula is as follows:

[0048] The rotation angle of the encoder 5 is given by formula (10):

[0049]

[0050] Where N is the number of pulses output by the encoder 5; C is the number of pulses output by the encoder 5 per revolution (the resolution of the encoder 5);

[0051] According to the rotation angle θ of the encoder 5, the moving distance D of the rotating wheel (with the encoder 5 sleeved) is calculated according to formula (11):

[0052]

[0053] Where θ is the rotation angle (in radians), R is the radius of the rotating wheel; D is the distance of the up and down movement of the rotating wheel;

[0054] Assume that during the measurement process, the encoder 5 records two key numbers of pulses, the total number of pulses N total represents the moving distance of the rotating wheel from the top of the liquid to the bottom of the liquid (i.e., the total height of the liquid in the tank); N oil represents the number of pulses from the top to the oil-water interface, then the following measurement results can be obtained:

[0055] Total liquid level height H total is calculated by formula (12):

[0056]

[0057] Oil liquid level height H oil is calculated by formula (13):

[0058]

[0059] Water liquid level height H water is calculated by formula (14):

[0060]

[0061] Since then, the oil liquid level height H in the tank 12 is obtained oiland the water level height H water 。

[0062] Embodiment 1

[0063] The structure of the liquid level measuring device in Embodiment 1 is that a power supply 7 and a motor driver 8 are installed on the upper surface outside the tank body 12; an explosion-proof motor 9, a fixed bracket 6 and a force sensor 4 are fixedly installed side by side at the top of the inner cavity of the tank body 12. The output shaft of the explosion-proof motor 9 is drivingly connected to a wire winding disc 10. A runner and its encoder 5 are arranged at the lower part of the fixed bracket 6, and a fixed pulley 3 is hung under the force sensor 4; the fixed end of the steel wire 2 is led out from the wire winding disc 10 and successively bypasses the runner and the fixed pulley 3, and the movable end of the steel wire 2 is connected with a solid ball 1; a controller 11 is further included. The controller 11 is in signal connection with the motor driver 8 and the encoder 5, and the motor driver 8 is in control connection with the explosion-proof motor 9.

[0064] According to the foregoing method process, the oil-water level height in a certain tank body is measured by using the device of the present utility model, and the recorded values are as follows:

[0065]

[0066]

[0067] By comparing this value with the data measured manually by the existing method, it is determined that the measurement result of the present utility model is more accurate.

[0068] Embodiment 2

[0069] The structure of the liquid level measuring device in Embodiment 2 is that a power supply 7 and a motor driver 8 are installed on the upper surface outside the tank body 12; an explosion-proof motor 9, a fixed bracket 6 and a force sensor 4 are fixedly installed side by side at the top of the inner cavity of the tank body 12. The output shaft of the explosion-proof motor 9 is drivingly connected to a wire winding disc 10. A runner and its encoder 5 are arranged at the lower part of the fixed bracket 6, and a fixed pulley 3 is hung under the force sensor 4; the fixed end of the steel wire 2 is led out from the wire winding disc 10 and successively bypasses the runner and the fixed pulley 3, and the movable end of the steel wire 2 is connected with a solid ball 1; a controller 11 is further included. The controller 11 is in signal connection with the motor driver 8 and the encoder 5, and the motor driver 8 is in control connection with the explosion-proof motor 9. The force sensor 4 is used to collect the pulling force value of the solid ball 1; the motor driver 8, the explosion-proof motor 9 and the wire winding disc 10 are linked and rotated together, that is, to control the releasing speed and the winding speed of the steel wire 2.

[0070] Embodiment 3

[0071] The structure of the liquid level measuring device of Embodiment 3 is as follows: a power supply 7 and a motor driver 8 are installed on the upper surface outside the tank body 12; an explosion-proof motor 9, a fixed bracket 6 and a force sensor 4 are fixedly installed side by side at the top of the inner cavity of the tank body 12. The output shaft of the explosion-proof motor 9 is drivingly connected to a wire winding disc 10. A runner and its encoder 5 are arranged at the lower part of the fixed bracket 6. A fixed pulley 3 is hung under the force sensor 4; the fixed end of the steel wire 2 is led out from the wire winding disc 10 and successively bypasses the runner and the fixed pulley 3. The movable end of the steel wire 2 is connected with a solid ball 1; further included is a controller 11, which is in signal connection with the motor driver 8 and the encoder 5, and the motor driver 8 is in control connection with the explosion-proof motor 9. The encoder 5 is used to output the actual rotation speed of the runner, that is, the lifting speed of the steel wire 2; the controller 11 is used to coordinate the work of the foregoing electrical components, collect relevant data, and accurately obtain the layered heights of the oil surface and the water surface in the tank body 12 by adopting the following operation process.

Claims

1. A liquid level measuring device for an oil gathering tank, characterized in that: A measuring platform (13) is arranged above the tank body (12), and a power supply (7) and a motor driver (8) are installed on the upper surface of the measuring platform (13); an explosion-proof motor (9), a fixed bracket (6) and a force sensor (4) are respectively fixed on the top of the inner cavity of the tank body (12); the output shaft of the explosion-proof motor (9) is drivingly connected to the winding drum (10), a rotating wheel and an encoder (5) are arranged at the lower part of the fixed bracket (6), and a fixed pulley (3) is hooked below the force sensor (4); the fixed end of the steel wire (2) is led out from the winding drum (10), and passes around the rotating wheel and the fixed pulley (3) in turn, and the movable end of the steel wire (2) is connected to a solid ball (1); and a controller (11) is also included, and the controller (11) is signal-connected to the motor driver (8), the encoder (5) and the force sensor (4), and the motor driver (8) is control-connected to the explosion-proof motor (9).

2. The liquid level measuring device for a petroleum gathering tank according to claim 1 is characterized in that: The force sensor (4) is used to collect the tensile force value of the solid ball (1).

3. The liquid level measuring device for a petroleum gathering tank according to claim 1 is characterized in that: The motor driver (8), explosion-proof motor (9) and winding drum (10) rotate together in a linked manner.

4. The liquid level measuring device for a petroleum gathering tank according to claim 1, characterized in that: The encoder (5) is used to output the actual rotation speed of the rotating wheel, that is, the lifting speed of the steel wire (2).

5. The liquid level measuring device for a petroleum gathering tank according to claim 1, characterized in that: The pulley (3), the rotating wheel where the encoder (5) is located, and the winding disk (10) together form a movable pulley group.

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