Online calibration system for pressure sensor of low-temperature storage tank of test bed

Abstract

The utility model provides an on-line calibration system for a pressure sensor of a low-temperature storage tank of a test bed. The on-line calibration system comprises a nitrogen collection module, a low-temperature storage tank module, a nitrogen distribution plate, a storage tank discharge module and a collection pipe discharged liquid collection tank. Wherein the nitrogen distribution plate is connected with the low-temperature storage box module and the nitrogen collection module. And the nitrogen collection module communicates with the low-temperature storage box module through a communicating pipeline. And the nitrogen collecting module is communicated with the collecting pipe discharged liquid collecting tank through a collecting pipe emptying pipeline. The nitrogen gathering module and the low-temperature storage box module are both communicated with the storage box discharging module. The low-temperature storage box module is provided with a first pressure detection module and a second pressure detection module. And a pressure detection and calibration module for calibrating the first pressure detection module and the second pressure detection module is arranged on the nitrogen collection module. According to the calibration system, the nitrogen collecting pipe and the pressure sensor arranged on the gas supply pipeline of the nitrogen collecting pipe are adopted to carry out online calibration on the pressure sensor of the low-temperature storage tank, and the detection efficiency is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of measuring tool calibration of a liquid rocket engine test bench, in particular to an online calibration system for a pressure sensor of a low-temperature storage tank of a test bench. Background Art

[0002] Before the liquid oxygen and methane liquid rocket engine is tested on the test bench, it is first necessary to use the nitrogen booster system to boost the liquid oxygen and liquid methane propellant cryogenic tanks respectively. When the pressure value of the tank reaches the set value, the liquid oxygen and liquid methane propellants are then transported to the rocket engine by booster transportation for ignition test. If during the engine ignition test, the tank pressure sensor of the liquid oxygen or liquid methane propellant cryogenic tank has a deviation, causing the pressure value to be high or low, the propellant mixing ratio entering the engine will be deviated, and the engine will be ablated or the propellant will be insufficiently powered when entering the engine, causing the engine's liquid oxygen pump or liquid methane pump to cavitate, etc., resulting in the failure of the ignition test. Therefore, before the engine ignition test, the tank pressure sensor needs to be calibrated.

[0003] At present, the calibration of pressure sensors usually requires the pressure sensors to be removed from the tank and then calibrated offline. This operation takes a relatively long time, thus affecting the test progress and efficiency of the engine. Utility Model Content

[0004] The utility model aims to overcome the deficiencies of the prior art and provide an online calibration system for a pressure sensor of a low-temperature storage tank of a test bench, so as to solve the problems of low detection efficiency and complicated operation of the pressure sensor in the prior art.

[0005] The utility model provides an online calibration system for a pressure sensor of a low-temperature storage tank of a test bench, and the online calibration system comprises: a nitrogen assembly module, a low-temperature storage tank module, a nitrogen distribution plate, a storage tank discharge module and a collection pipe drainage collection tank, wherein the nitrogen distribution plate is connected to the low-temperature storage tank module through a storage tank nitrogen pipeline for providing nitrogen; the nitrogen distribution plate is connected to the nitrogen assembly module through a collection pipe nitrogen pipeline for providing nitrogen; the nitrogen assembly module is connected to the low-temperature storage tank module through a connecting pipeline; the nitrogen assembly module and the low-temperature storage tank module are both connected to the storage tank discharge module for gas discharge; the low-temperature storage tank module is provided with a first pressure detection module and a second pressure detection module; the nitrogen assembly module is provided with a pressure detection calibration module for calibration with the first pressure detection module and the second pressure detection module.

[0006] Furthermore, the nitrogen assembly module includes a nitrogen assembly pipe and at least one third pressure detection module, wherein the nitrogen assembly pipe is a sealed tube body, and the third pressure detection module is arranged on the nitrogen assembly pipe to detect the internal pressure value of the nitrogen assembly pipe and compare and calibrate it with the detection values ​​of the first pressure detection module and the second pressure detection module.

[0007] Furthermore, the third pressure detection module includes a manifold remote pressure sensor and a manifold on-site pressure gauge, the manifold remote pressure sensor and the manifold on-site pressure gauge are connected to the interior of the nitrogen manifold through a sensor pipeline, and a sensor root valve is provided at the root of the sensor pipeline connected to the nitrogen manifold.

[0008] Furthermore, the cryogenic storage tank module also includes a cryogenic storage tank, the first pressure detection module is arranged at the bottom of the cryogenic storage tank, and is used to detect the pressure value at the bottom of the cryogenic storage tank; the second pressure detection module is arranged at the top of the cryogenic storage tank, and is used to detect the pressure value at the top of the cryogenic storage tank; the first pressure detection module includes: a remote pressure sensor at the bottom of the storage tank and an on-site pressure gauge at the bottom of the storage tank, the remote pressure sensor at the bottom of the storage tank and the on-site pressure gauge at the bottom of the storage tank are connected to the tank liquid outlet pipe at the bottom of the cryogenic storage tank through a sensor pipeline; the second pressure detection module includes: a remote pressure sensor at the top of the storage tank and an on-site pressure gauge at the top of the storage tank, the remote pressure sensor at the top of the storage tank and the on-site pressure gauge at the top of the storage tank are connected to the top of the cryogenic storage tank through a sensor pipeline, and are used to detect the pressure value at the top of the cryogenic storage tank.

[0009] Further, one end of the tank nitrogen pipeline is connected to the nitrogen gas distribution plate, and the other end is connected to the interior of the low-temperature storage tank, and a nitrogen boost energy dissipation valve for reducing the kinetic energy of nitrogen transportation is provided at the end; a tank nitrogen boost valve is provided on the tank nitrogen pipeline, and nitrogen boost bypass pipelines are provided at both ends of the tank nitrogen boost valve, and a nitrogen boost bypass valve is provided on the nitrogen boost bypass pipeline; a first nitrogen boost flow limiting plate for limiting the flow of nitrogen is also provided on the tank nitrogen pipeline; a nitrogen boost filter for filtering the nitrogen gas flow is also provided on the tank nitrogen pipeline.

[0010] Furthermore, the top of the cryogenic tank is connected to the tank discharge module through a tank discharge pipe; a tank discharge valve for controlling the opening and closing of the pipe is provided on the tank discharge pipe, and tank discharge bypass pipes are provided at both ends of the tank discharge valve, and a tank discharge bypass valve is provided on the tank discharge bypass pipe; the nitrogen manifold is connected to the tank discharge pipe through a manifold exhaust pipe and is connected to the tank discharge module, and a manifold exhaust valve for controlling the opening and closing of the pipe is provided on the manifold exhaust pipe.

[0011] Furthermore, a manifold self-operated discharge pipe is provided between the nitrogen manifold and the manifold exhaust pipe to prevent excessive pressure in the nitrogen manifold, and a manifold exhaust self-operated regulating valve is provided on the manifold self-operated discharge pipe; a manifold exhaust check valve is provided on the manifold exhaust pipe, and is located between the connection between the manifold exhaust pipe and the manifold self-operated discharge pipe and the connection between the manifold exhaust pipe and the tank exhaust pipe.

[0012] In an embodiment of the utility model, one end of the manifold nitrogen pipeline is connected to the storage tank nitrogen pipeline, and the other end is connected to the nitrogen manifold; a manifold nitrogen inlet valve is provided on the manifold nitrogen pipeline, and a manifold nitrogen bypass pipeline is connected to both ends of the nitrogen inlet valve, and a nitrogen inlet bypass valve is provided on the manifold nitrogen bypass pipeline; a fourth pressure detection module is provided on the manifold nitrogen pipeline, and the fourth pressure detection module includes a nitrogen inlet pipe remote pressure sensor and a nitrogen inlet pipe on-site pressure gauge, which are used to detect the pressure value on the manifold nitrogen pipeline; a second nitrogen boost limiting plate for limiting the nitrogen flow is also provided on the manifold nitrogen pipeline; a manifold nitrogen filter for filtering the nitrogen gas flow is also provided on the manifold nitrogen pipeline; a manifold inlet check valve for checking the gas flow is provided on the manifold nitrogen pipeline.

[0013] In the implementation manner of the utility model, a connecting pipe control valve for controlling the opening and closing of the pipeline is arranged on the connecting pipe; a nitrogen intake pipe root valve for controlling the opening and closing of the pipeline is arranged at the root of the collecting pipe nitrogen pipeline connected to the nitrogen collecting pipe.

[0014] The nitrogen collection module is connected to the collection pipe drainage collection tank through a collection pipe drain pipeline; a collection pipe drain valve for controlling the opening and closing of the pipeline is arranged on the collection pipe drain pipeline.

[0015] According to the above-mentioned embodiments, the online calibration system for the pressure sensor of the low-temperature storage tank of the test bench provided by the utility model has at least the following benefits: the online calibration system adopts a nitrogen manifold to connect the nitrogen supply pipeline, the exhaust pipeline and the low-temperature storage tank, and performs online calibration on the pressure sensor of the low-temperature storage tank through the nitrogen manifold and the pressure sensor arranged on the supply pipeline, thereby improving the detection efficiency.

[0016] The multiple pressure sensors arranged on the nitrogen manifold of the online calibration system can improve the detection accuracy by cooperating with the pressure sensors on the gas supply pipeline. At the same time, the calibration system can greatly reduce the detection error and improve the accuracy of the online calibration through multiple online calibrations.

[0017] In addition, the online calibration system uses a collection tube instead of a traditional storage tank as a buffer device for pressure sensor calibration, reducing the investment cost of the equipment.

[0018] It should be understood that the above general description and the following specific embodiments are only exemplary and illustrative and are not intended to limit the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The following drawings are a part of the specification of the present utility model, which illustrate exemplary embodiments of the present utility model. The attached drawings and the description of the specification are used to explain the principle of the present utility model.

[0020] Figure 1 The utility model provides a structural schematic diagram of an online calibration system for a pressure sensor of a low-temperature storage tank of a test bench.

[0021] Description of reference numerals:

[0022] 1-nitrogen assembly module, 2-cryogenic storage tank module, V-cryogenic storage tank, J-nitrogen assembly pipe, N-nitrogen distribution board, Q-storage tank discharge module, S-assembly pipe drainage collection tank;

[0023] a0-tank liquid outlet pipe, a1-tank nitrogen pipe, a2-nitrogen boost bypass pipe, a3-tank discharge pipe, a4-tank discharge bypass pipe, a5-connecting pipe; b0-manifold exhaust pipe, b1-manifold nitrogen pipe, b2-manifold nitrogen bypass pipe, b3-manifold exhaust pipe, b4-manifold self-powered discharge pipe;

[0024] L-liquid level gauge, k1-first nitrogen boost flow limiting plate, k2-second nitrogen boost flow limiting plate, g1-nitrogen boost filter, g2-manifold nitrogen filter, X-nitrogen boost energy dissipator, z1-manifold intake check valve, z2-manifold exhaust check valve, P0-tank bottom remote pressure sensor, C0-tank bottom on-site pressure gauge, P1-tank top remote pressure sensor, C1-tank top on-site pressure gauge, P2 and P3-manifold remote pressure sensor, C2 and C3-manifold on-site pressure gauge, P4-nitrogen intake pipe remote pressure sensor, C4-nitrogen intake pipe on-site pressure gauge, Y0, Y1, Y2, Y3, Y4-sensor root valve;

[0025] A0-tank bottom liquid outlet valve, A1-tank nitrogen boost valve, A2-nitrogen boost bypass valve, A3-connecting pipe control valve, A4-manifold drain valve, A5-tank discharge valve, A6-tank discharge bypass valve, B1-manifold nitrogen inlet valve, B2-nitrogen inlet bypass valve, B3-nitrogen inlet pipe root valve, B4-manifold exhaust valve, B5-manifold exhaust self-operated regulating valve. DETAILED DESCRIPTION

[0026] Various exemplary embodiments of the present invention are now described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features and embodiments of the present invention.

[0027] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention will be apparent to those skilled in the art. The present application description and examples are merely exemplary.

[0028] The utility model provides an online calibration system for pressure sensors of a low-temperature storage tank of a test bench, such as Figure 1 The structure diagram of the calibration system is shown in FIG. In a specific implementation, the online calibration system includes: a nitrogen assembly module 1, a cryogenic storage tank module 2, a nitrogen distribution board N, a storage tank discharge module Q, and a collection pipe drainage collection tank S. The nitrogen distribution board N is connected to the cryogenic storage tank module 2 through a storage tank nitrogen pipeline a1 to provide nitrogen.

[0029] The nitrogen distribution plate N is connected to the nitrogen collection module 1 through the collection pipe nitrogen pipeline b1 to provide nitrogen.

[0030] The nitrogen collection module 1 is connected to the low-temperature storage tank module 2 via a connecting pipe a5.

[0031] The nitrogen assembly module 1 is connected to the manifold drainage collection tank S through the manifold drainage pipe b0.

[0032] The nitrogen assembly module 1 and the cryogenic storage tank module 2 are both connected to the storage tank discharge module Q for gas discharge.

[0033] The low-temperature storage tank module 2 is provided with a first pressure detection module and a second pressure detection module, which are used to detect the pressures at the top and bottom of the low-temperature storage tank module 2 respectively.

[0034] A pressure detection calibration module for calibration with the first pressure detection module and the second pressure detection module is provided on the nitrogen assembly module 1. In this embodiment, by comparing and evaluating the value of the pressure detection calibration module on the nitrogen assembly module 1 with the values ​​on the first pressure detection module and the second pressure detection module, it is determined whether the first pressure detection module and the second pressure detection module are normal, and the sensor module is calibrated.

[0035] In a specific embodiment of the utility model, the nitrogen assembly module 1 includes a nitrogen manifold J and at least one third pressure detection module. The nitrogen manifold J is a sealed tube body, and the third pressure detection module is arranged on the nitrogen manifold J, which is used to detect the internal pressure value of the nitrogen manifold J, and compare and calibrate with the detection values ​​of the first pressure detection module and the second pressure detection module. In this embodiment, two groups of third pressure detection modules are arranged on the nitrogen manifold J, which are used to improve the accuracy of detection through multiple groups of data. In addition, the third pressure detection module is a pressure detection calibration module.

[0036] Furthermore, the third pressure detection module includes a manifold remote pressure sensor P2 and a manifold on-site pressure gauge C2. The manifold remote pressure sensor P2 and the manifold on-site pressure gauge C2 are connected to the interior of the nitrogen manifold J through a sensor pipeline. A sensor root valve Y2 is provided at the root of the sensor pipeline connected to the nitrogen manifold J.

[0037] Furthermore, in the present embodiment, another group of third pressure detection modules also includes a manifold remote pressure sensor P3 and a manifold on-site pressure gauge C3. The manifold remote pressure sensor P3 and the manifold on-site pressure gauge C3 are connected to the interior of the nitrogen manifold J through a sensor pipeline. A sensor root valve Y3 is provided at the root of the sensor pipeline connected to the nitrogen manifold J.

[0038] In a specific implementation of the present invention, the cryogenic storage tank module 2 further comprises a cryogenic storage tank V, and the first pressure detection module is arranged at the bottom of the cryogenic storage tank V to detect the pressure value at the bottom of the cryogenic storage tank V.

[0039] The second pressure detection module is arranged at the top of the cryogenic tank V, and is used to detect the pressure value at the top of the cryogenic tank V. The pressure value P0 at the bottom of the tank is the tank top pressure P plus the hydrostatic column pressure PL=ρgh of the propellant liquid, which is P0=P+PL.

[0040] The first pressure detection module includes: a remote pressure sensor P0 at the bottom of the tank and a local pressure gauge C0 at the bottom of the tank. The remote pressure sensor P0 at the bottom of the tank and the local pressure gauge C0 at the bottom of the tank are connected to the tank liquid outlet pipe a0 at the bottom of the low-temperature tank V through a sensor pipeline. A sensor root valve Y0 is provided on the sensor pipeline to control the opening and closing of the sensor pipeline. In addition, a tank bottom liquid outlet valve A0 is provided on the tank liquid outlet pipe a0 to control the opening and closing of the tank liquid outlet pipe a0, thereby controlling the discharge of liquid in the low-temperature tank V.

[0041] The second pressure detection module includes: a remote pressure sensor P1 on the top of the tank and a local pressure gauge C1 on the top of the tank. The remote pressure sensor P1 on the top of the tank and the local pressure gauge C1 on the top of the tank are connected to the top of the low-temperature tank V through a sensor pipeline to detect the pressure value on the top of the low-temperature tank V. A sensor root valve Y1 is provided on the sensor pipeline to control the opening and closing of the sensor pipeline.

[0042] The cryogenic tank module 2 further includes a liquid level gauge L, which is disposed on the top of the cryogenic tank V and extends below the propellant liquid level in the cryogenic tank V to detect the propellant liquid level.

[0043] Furthermore, one end of the tank nitrogen pipeline a1 is connected to the nitrogen distribution plate N, and the other end is connected to the interior of the cryogenic tank V, and a nitrogen boost energy dissipation valve X is provided at the end for reducing the kinetic energy of nitrogen transportation to prevent the pressurized nitrogen from directly rushing to the liquid surface of the propellant, causing liquid fluctuations, thereby affecting the measurement of the liquid level.

[0044] The tank nitrogen boosting valve A1 is provided on the tank nitrogen pipeline a1, which is used to control the on / off solenoid valve when the tank nitrogen is boosted. The tank top remote pressure sensor P1 and the tank bottom remote pressure sensor P0 are electrically connected to the tank nitrogen boosting valve A1, which is used to control the on / off of the tank nitrogen boosting valve A1 according to the detection signals of the tank top remote pressure sensor P1 and the tank bottom remote pressure sensor P0.

[0045] A nitrogen boost bypass pipe a2 is connected to both ends of the nitrogen boost valve A1 of the tank, and a nitrogen boost bypass valve A2 is arranged on the nitrogen boost bypass pipe a2. In this embodiment, the nitrogen boost bypass valve A2 is a manual stop valve, which is convenient for on-site personnel to manually switch on and off the nitrogen boost of the tank.

[0046] The tank nitrogen pipeline a1 is also provided with a first nitrogen boost flow limiting plate k1 for limiting the flow of nitrogen. The first nitrogen boost flow limiting plate k1 is used to limit the flow of the boosted nitrogen to prevent the boosted nitrogen from flowing too fast. Compared with other types of gas flow meters for flow control, the investment cost of the flow limiting orifice is lower.

[0047] The tank nitrogen pipeline a1 is also provided with a nitrogen boost filter g1 for filtering the nitrogen gas flow.

[0048] Furthermore, the top of the low-temperature storage tank V is connected to the tank discharge module Q through the tank discharge pipe a3.

[0049] The tank discharge pipe a3 is provided with a tank discharge valve A5 for controlling the opening and closing of the pipe, and both ends of the tank discharge valve A5 are connected with a tank discharge bypass pipe a4, and a tank discharge bypass valve A6 is provided on the tank discharge bypass pipe a4. In this embodiment, the tank discharge bypass valve A6 is a manual stop valve, which is convenient for on-site personnel to manually control the discharge of nitrogen from the tank.

[0050] The nitrogen manifold J is connected to the tank exhaust pipe a3 through the manifold exhaust pipe b3, and is connected to the tank exhaust module Q. A manifold exhaust valve B4 is provided on the manifold exhaust pipe b3 to control the opening and closing of the pipe. The manifold remote pressure sensor P2 and the manifold remote pressure sensor P3 are connected to the manifold exhaust valve B4 by electrical connection, and the opening and closing of the manifold exhaust valve B4 are controlled by the pressure values ​​of the manifold remote pressure sensor P2 and the manifold remote pressure sensor P3.

[0051] Furthermore, a manifold self-operated discharge pipe b4 is provided between the nitrogen manifold J and the manifold exhaust pipe b3 to prevent excessive pressure in the nitrogen manifold J. A manifold exhaust self-operated regulating valve B5 is provided on the manifold self-operated discharge pipe b4.

[0052] When the nitrogen inlet valve B1 of the manifold is opened to introduce nitrogen into the nitrogen manifold J for pressurization, when the pressure value of the nitrogen manifold J reaches the threshold value of the manifold exhaust self-operated regulating valve B5, the valve of the manifold exhaust self-operated regulating valve B5 automatically opens and discharges gas, and the exhaust gas is discharged from the manifold exhaust self-operated regulating valve B5 and the manifold self-operated exhaust pipeline b4 to the manifold exhaust pipeline b3 to prevent the manifold from overpressure. When the pressure value of the nitrogen manifold J is less than the threshold value of the manifold exhaust self-operated regulating valve B5, the manifold exhaust self-operated regulating valve B5 automatically closes.

[0053] In this embodiment, the self-opening pressure value of the manifold exhaust self-operated regulating valve B5 is set to 1.5MPa. When the nitrogen intake valve B1 of the manifold is opened to pass nitrogen into the nitrogen manifold J for pressurization, when the pressure value of the nitrogen manifold J is ≥1.5MPa, the manifold exhaust self-operated regulating valve B5 automatically opens to discharge gas. The exhaust gas is discharged from the manifold exhaust self-operated regulating valve B5 and the manifold self-operated exhaust pipe b4 to the manifold exhaust pipe b3 to prevent the manifold from overpressure. When the pressure value of the nitrogen manifold J is less than 1.5MPa, the manifold exhaust self-operated regulating valve B5 automatically closes.

[0054] In addition, a manifold exhaust check valve z2 is provided on the manifold exhaust pipe b3. The manifold exhaust check valve z2 is located between the connection between the manifold exhaust pipe b3 and the manifold self-powered exhaust pipe b4 and the connection between the manifold exhaust pipe b3 and the tank exhaust pipe a3, and is used to prevent gas reflux.

[0055] In the specific implementation of the utility model, one end of the manifold nitrogen pipeline b1 is connected to the tank nitrogen pipeline a1, and the other end is connected to the nitrogen manifold J. Nitrogen starts from the nitrogen distribution board N, passes through the tank nitrogen pipeline a1 and the manifold nitrogen pipeline b1 in sequence, and enters the nitrogen manifold J.

[0056] In addition, a manifold nitrogen inlet valve B1 is provided on the manifold nitrogen pipeline b1, and a manifold nitrogen bypass pipeline b2 is connected to both ends of the nitrogen inlet valve B1, and a nitrogen inlet bypass valve B2 is provided on the manifold nitrogen bypass pipeline b2;

[0057] The manifold remote pressure sensor P2 and the manifold remote pressure sensor P3 are electrically connected to the manifold nitrogen intake valve B1, and the opening and closing of the manifold nitrogen intake valve B1 are controlled by the pressure values ​​of the manifold remote pressure sensor P2 and the manifold remote pressure sensor P3.

[0058] Furthermore, a fourth pressure detection module is provided on the manifold nitrogen pipeline b1, and the fourth pressure detection module includes a nitrogen intake pipe remote pressure sensor P4 and a nitrogen intake pipe on-site pressure gauge C4, which are used to detect the pressure value on the manifold nitrogen pipeline b1. The nitrogen intake pipe remote pressure sensor P4 and the nitrogen intake pipe on-site pressure gauge C4 are connected to the manifold nitrogen pipeline b1 through a sensor pipeline, and a sensor root valve Y4 is provided on the sensor pipeline to control the opening and closing of the sensor pipeline. The nitrogen intake pipe remote pressure sensor P4 is electrically connected to the manifold nitrogen intake valve B1 and the manifold exhaust valve B4, and the opening and closing of the manifold nitrogen intake valve B1 and the manifold exhaust valve B4 are controlled by the pressure value of the nitrogen intake pipe remote pressure sensor P4.

[0059] In addition, a second nitrogen boost flow limiting plate k2 for limiting the flow of nitrogen is also provided on the manifold nitrogen pipeline b1. The second nitrogen boost flow limiting plate k2 is used to limit the flow of the boosted nitrogen to prevent the boosted nitrogen from flowing too fast. Compared with other types of gas flow meters for flow control, the investment cost of the flow limiting orifice is less.

[0060] The manifold nitrogen pipeline b1 is also provided with a manifold nitrogen filter g2 for filtering the nitrogen gas flow.

[0061] The manifold nitrogen pipeline b1 is provided with a manifold air inlet check valve z1 for checking the air flow.

[0062] In a specific embodiment of the utility model, a connecting pipe control valve A3 for controlling the opening and closing of the pipeline is provided on the connecting pipe a5. The manifold remote pressure sensor P2, the manifold remote pressure sensor P3 and the nitrogen intake pipe remote pressure sensor P4 are electrically connected to the connecting pipe control valve A3, and the opening and closing of the connecting pipe control valve A3 are controlled by the pressure values ​​of the manifold remote pressure sensor P2, the manifold remote pressure sensor P3 and the nitrogen intake pipe remote pressure sensor P4.

[0063] A manifold drain valve A4 for controlling the opening and closing of the pipeline is provided on the manifold drain pipeline b0.

[0064] The root of the nitrogen collecting pipe b1 connected to the nitrogen collecting pipe J is provided with a nitrogen inlet pipe root valve B3 for controlling the opening and closing of the pipeline.

[0065] The implementation method of the online calibration system for the pressure sensor of the low temperature storage tank of the test bench includes:

[0066] Step 1: Before calibrating the tank pressure sensor of the propellant cryogenic tank with nitrogen pressurization.

[0067] First, open the exhaust valve B4 of the manifold to exhaust the gas in the nitrogen manifold J to avoid the existence of additional pressure that affects the calibration of the sensor. When the pressure in the nitrogen manifold J reaches the normal pressure value, close the exhaust valve B4 of the manifold.

[0068] Then, the nitrogen intake valve B1 of the manifold is remotely started to open to introduce nitrogen into the nitrogen manifold J, and the boost pressure value of the nitrogen manifold J is set to P. Nitrogen is drawn from the nitrogen pipeline a1 of the storage tank, and enters the nitrogen manifold J from the nitrogen pipeline b1 through the nitrogen intake valve B1 of the manifold, the intake check valve z1 of the manifold, the second nitrogen boost flow limiting plate k2, the nitrogen filter g2 of the manifold, and the root valve B3 of the nitrogen intake pipe. When the pressure value of the remote pressure sensor P4 of the nitrogen intake pipe reaches the value P, the sensor signal is fed back to the nitrogen intake valve B1 of the manifold to execute the closing command. If the pressure values ​​of the remote pressure sensors P2 and P3 of the manifolds are both P2=P3=P4=P at this time, it indicates that the remote pressure sensors P2 and P3 of the manifolds are working normally. In addition, if manual operation is required on site to pressurize the collecting pipe, the nitrogen intake bypass valve B2 can be opened manually, and the nitrogen intake bypass valve B2 can be closed manually when the nitrogen intake pipe on-site pressure gauge C4 reaches the P value.

[0069] When the nitrogen inlet valve B1 of the manifold is opened to increase the pressure of nitrogen manifold J, when the pressure value of nitrogen manifold J is ≥1.5MPa, the manifold exhaust self-operated regulating valve B5 automatically opens to discharge gas. The exhaust gas is discharged from the manifold exhaust self-operated regulating valve B5 and the manifold self-operated exhaust pipe b4 to the manifold exhaust pipe b3 to prevent the manifold from overpressure. When the pressure value of nitrogen manifold J is less than 1.5MPa, the manifold exhaust self-operated regulating valve B5 automatically closes.

[0070] Step 2: When calibrating the tank pressure sensor of the propellant cryogenic tank with nitrogen pressurization.

[0071] First, open the manifold exhaust valve B4 to exhaust the gas in the nitrogen manifold J to avoid the existence of additional pressure, which will affect the calibration of the sensor. When the pressure in the nitrogen manifold J reaches the normal pressure value, close the manifold exhaust valve B4.

[0072] Then, open the connecting pipe control valve A3 to connect the top of the tank to the nitrogen manifold J through the connecting pipe a5. Remotely start and open the tank nitrogen boost valve A1, and the nitrogen is output from the nitrogen distribution panel N. The nitrogen is transported from the tank nitrogen pipeline a1 to the low-temperature tank V through the tank nitrogen boost valve A1, the first nitrogen boost flow limiting plate k1, the nitrogen boost filter g1, and the nitrogen boost energy dissipator X. The boost pressure value of the remote pressure sensor P1 on the top of the tank is set to P1. If manual operation is required on site to boost the tank, the nitrogen boost bypass valve A2 can be manually opened, and the nitrogen boost bypass valve A2 can be manually closed when the on-site pressure gauge C1 on the top of the tank reaches the value of P1.

[0073] When the remote pressure sensor P1 at the top of the tank reaches the pressure value P1, the pressure signal is fed back to the tank nitrogen booster valve A1 and a closing command is executed. According to the principle of communicating vessels, if the pressure values ​​of the manifold remote pressure sensors P2 and P3 at this time are consistent with the remote pressure sensor P1 at the top of the tank, that is, P2=P3=P1=P1, it indicates that the remote pressure sensor P1 at the top of the tank is working properly. The pressure value P0 at the bottom of the tank is the pressure P1 at the top of the tank plus the hydrostatic column pressure PL=ρgh of the propellant liquid at this time, which is P0=P1+PL. Since the height value h of the liquid column does not change, the hydrostatic column pressure value PL is a constant value, so it can be determined that the remote pressure sensor P0 at the bottom of the tank is working properly.

[0074] Finally, when the low-temperature tank V is exhausted, the tank discharge valve A5 is opened, and the exhaust gas of the tank is discharged from the tank discharge pipe a3 through the tank discharge valve A5 to the tank discharge module Q. When the pressure value of the remote pressure sensor P1 on the top of the tank reaches normal pressure, the tank discharge valve A5 is closed. If manual exhaust is required on site, the tank discharge bypass valve A6 can be manually opened to discharge the gas.

[0075] When dirty liquid or excess material exists in the nitrogen manifold J and needs to be discharged, the manifold drain valve A4 is opened to discharge the dirty liquid or excess material in the nitrogen manifold J through the manifold drain pipe b0 to the manifold drain collection tank S.

[0076] Step 3: Repeat the online calibration of the tank pressure sensor several times to determine the accuracy of the sensor.

[0077] According to step 2 when the low-temperature tank is pressurized with nitrogen, the remote pressure sensor P1 on the top of the tank is calibrated online for multiple times. If the calibration values ​​of the pressure sensors on the top and bottom of the tank are consistent after multiple calibrations, it is finally confirmed that the pressure sensors on the top and bottom of the tank are working properly and their accuracy meets the test requirements.

[0078] The above description is only an illustrative specific implementation of the present invention. Without departing from the concept and principle of the present invention, any equivalent changes and modifications made by those skilled in the art should fall within the scope of protection of the present invention.

Claims

1. An online calibration system for pressure sensors of a test bench cryogenic storage tank, characterized in that: The online calibration system comprises: a nitrogen collection module (1), a low temperature storage tank module (2), a nitrogen distribution plate (N), a storage tank discharge module (Q) and a collection pipe drainage collection tank (S), wherein: The nitrogen distribution plate (N) is connected to the low-temperature storage tank module (2) via a storage tank nitrogen pipeline (a1) to provide nitrogen; The nitrogen distribution plate (N) is connected to the nitrogen collection module (1) via a collection pipe nitrogen pipeline (b1) to provide nitrogen; The nitrogen collection module (1) is connected to the low-temperature storage tank module (2) via a connecting pipe (a5); The nitrogen collection module (1) and the low-temperature storage tank module (2) are both connected to a storage tank discharge module (Q) for gas discharge; The low-temperature storage tank module (2) is provided with a first pressure detection module and a second pressure detection module; The nitrogen assembly module (1) is provided with a pressure detection calibration module for calibrating the first pressure detection module and the second pressure detection module.

2. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 1 is characterized in that: The nitrogen collection module (1) comprises a nitrogen collection pipe (J) and at least one third pressure detection module, wherein: The nitrogen manifold (J) is a sealed tube body, and the third pressure detection module is arranged on the nitrogen manifold (J) to detect the internal pressure value of the nitrogen manifold (J) and compare and calibrate it with the detection values ​​of the first pressure detection module and the second pressure detection module.

3. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 2 is characterized in that: The third pressure detection module comprises a manifold remote pressure sensor (P2) and a manifold on-site pressure gauge (C2), wherein the manifold remote pressure sensor (P2) and the manifold on-site pressure gauge (C2) are connected to the interior of the nitrogen manifold (J) through a sensor pipeline, and a sensor root valve (Y2) is provided at the root of the sensor pipeline connected to the nitrogen manifold (J).

4. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 2 is characterized in that: The low-temperature storage tank module (2) further comprises a low-temperature storage tank (V), wherein the first pressure detection module is arranged at the bottom of the low-temperature storage tank (V) and is used to detect the pressure value at the bottom of the low-temperature storage tank (V); The second pressure detection module is arranged at the top of the cryogenic storage tank (V) and is used to detect the pressure value at the top of the cryogenic storage tank (V); The first pressure detection module comprises: a remote pressure sensor (P0) at the bottom of the tank and an on-site pressure gauge (C0) at the bottom of the tank, wherein the remote pressure sensor (P0) at the bottom of the tank and the on-site pressure gauge (C0) at the bottom of the tank are connected to a tank liquid outlet pipe (a0) at the bottom of the low-temperature tank (V) through a sensor pipeline; The second pressure detection module comprises: a tank top remote pressure sensor (P1) and a tank top on-site pressure gauge (C1); the tank top remote pressure sensor (P1) and the tank top on-site pressure gauge (C1) are connected to the top of the cryogenic tank (V) through a sensor pipeline, and are used to detect the pressure value at the top of the cryogenic tank (V).

5. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 4 is characterized in that: One end of the tank nitrogen pipeline (a1) is connected to the nitrogen gas distribution plate (N), and the other end is connected to the interior of the low-temperature storage tank (V), and a nitrogen boost energy dissipation valve (X) for reducing the kinetic energy of nitrogen transportation is provided at the end; The tank nitrogen pipeline (a1) is provided with a tank nitrogen boosting valve (A1), both ends of the tank nitrogen boosting valve (A1) are connected with a nitrogen boosting bypass pipeline (a2), and the nitrogen boosting bypass pipeline (a2) is provided with a nitrogen boosting bypass valve (A2); The tank nitrogen pipeline (a1) is also provided with a first nitrogen boost flow limiting plate (k1) for limiting the flow of nitrogen; The tank nitrogen pipeline (a1) is also provided with a nitrogen boost filter (g1) for filtering the nitrogen gas flow.

6. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 4 is characterized in that: The top of the low-temperature storage tank (V) is connected to the storage tank discharge module (Q) through a storage tank discharge pipeline (a3); The tank discharge pipe (a3) ​​is provided with a tank discharge valve (A5) for controlling the opening and closing of the pipe, both ends of the tank discharge valve (A5) are connected with a tank discharge bypass pipe (a4), and the tank discharge bypass pipe (a4) is provided with a tank discharge bypass valve (A6); The nitrogen manifold (J) is connected to the tank exhaust pipe (a3) ​​through a manifold exhaust pipe (b3), and is connected to the tank exhaust module (Q). The manifold exhaust pipe (b3) is provided with a manifold exhaust valve (B4) for controlling the opening and closing of the pipe.

7. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 6 is characterized in that: A manifold self-operated discharge pipe (b4) is provided between the nitrogen manifold (J) and the manifold exhaust pipe (b3) to prevent excessive pressure in the nitrogen manifold (J), and a manifold exhaust self-operated regulating valve (B5) is provided on the manifold self-operated discharge pipe (b4); The manifold exhaust pipe (b3) is provided with a manifold exhaust check valve (z2), which is located between the connection between the manifold exhaust pipe (b3) and the manifold self-powered exhaust pipe (b4) and the connection between the manifold exhaust pipe (b3) and the tank exhaust pipe (a3).

8. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 2 or 3, characterized in that: One end of the manifold nitrogen pipeline (b1) is connected to the tank nitrogen pipeline (a1), and the other end is connected to the nitrogen manifold (J); The manifold nitrogen pipeline (b1) is provided with a manifold nitrogen inlet valve (B1), both ends of the nitrogen inlet valve (B1) are connected with a manifold nitrogen bypass pipeline (b2), and the manifold nitrogen bypass pipeline (b2) is provided with a nitrogen inlet bypass valve (B2); The manifold nitrogen pipeline (b1) is provided with a fourth pressure detection module, the fourth pressure detection module comprising a nitrogen intake pipe remote pressure sensor (P4) and a nitrogen intake pipe on-site pressure gauge (C4), for detecting the pressure value on the manifold nitrogen pipeline (b1); The manifold nitrogen pipeline (b1) is also provided with a second nitrogen boost flow limiting plate (k2) for limiting the flow of nitrogen; The manifold nitrogen pipeline (b1) is also provided with a manifold nitrogen filter (g2) for filtering the nitrogen gas flow; The manifold nitrogen pipeline (b1) is provided with a manifold air inlet check valve (z1) for checking the flow of air.

9. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 2 is characterized in that: The connecting pipe (a5) is provided with a connecting pipe control valve (A3) for controlling the opening and closing of the pipeline; The root of the nitrogen collecting pipe (b1) connected to the nitrogen collecting pipe (J) is provided with a nitrogen inlet pipe root valve (B3) for controlling the opening and closing of the pipeline.

10. The pressure sensor online calibration system for the test bench cryogenic storage tank according to claim 1 is characterized in that: The nitrogen collection module (1) is connected to the collection pipe drainage collection tank (S) via the collection pipe exhaust pipe (b0); The manifold drain pipe (b0) is provided with a manifold drain valve (A4) for controlling the opening and closing of the pipeline.

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