A conical vacuum pump for gas transport

Abstract

The present application belongs to the technical field of vacuum pumps, and particularly relates to a conical vacuum pump for gas delivery, which comprises a pump body, the pump body being fixedly installed at one end of an output shaft of a motor, the output shaft of the motor being connected with a rotor, and the pump body being further provided with an air inlet pipe and an air outlet pipe, and further comprising: a gas leakage monitoring module for monitoring methane leakage caused by sealing failure in real time and generating a sealing failure coefficient through a control module; and a bearing state monitoring module for monitoring abnormal vibration caused by rotor imbalance or friction in real time and generating a mechanical friction coefficient through the control module. In the present application, methane leakage and mechanical vibration are monitored in real time, the sealing failure coefficient and the mechanical friction coefficient are quantified, and the risk level is dynamically judged through evaluation of the coefficients, so that the grading control of'slight risk speed reduction early warning-severe risk shutdown and gas cutting' is realized, and the risk of gas explosion caused by coupling of leakage and mechanical failure from the source is avoided.

Description

Technical Field

[0001] This invention relates to the field of vacuum pump technology, and more particularly to a conical vacuum pump for gas delivery. Background Technology

[0002] In fields such as coal mine gas extraction and chemical waste gas recovery, conical vacuum pumps are core equipment for transporting flammable and explosive gases. However, existing technologies have the following key defects, leading to frequent safety accidents:

[0003] 1. Seal failure leading to leaks and explosions (an industry pain point)

[0004] Traditional contact seals (such as packing seals): after long-term operation, wear creates micron-level gaps, and methane leaks slowly at a rate of 0.5-2 L / min.

[0005] Fatal flaw: Conventional pressure sensors fail to detect leaks in the early stages (pressure change <1%), and by the time the concentration reaches the lower explosive limit (5% LEL), a flammable cloud has already formed.

[0006] Existing solutions:

[0007] It adopts a double-end mechanical seal, but the static sealing pressure is not adjustable. When the medium contains dust, the sealing surface wears faster, and the risk of sudden leakage is high.

[0008] 2. Ignition source triggered by mechanical failure (technical gap)

[0009] High-speed rotor system (>10,000 rpm): When bearings wear or rotor is dynamically unbalanced, the local friction temperature rise can reach more than 500°C (far exceeding the ignition point of methane 538°C), and mechanical sparks are generated at the same time.

[0010] Monitoring shortcomings: The response lag of a single temperature sensor is >10s, making it unable to capture millisecond-level friction sparks; the vibration sensor only warns of equipment damage and does not associate it with the risk of explosion.

[0011] 3. Delayed security response mechanism (design limitations)

[0012] Passive safety systems:

[0013] The entire process of methane concentration exceeding the limit alarm → shutdown → depressurization takes more than 30 seconds, while methane only needs 5-10 seconds to diffuse to an explosive concentration.

[0014] The inerting system needs to be started manually, which delays the golden time for treatment.

[0015] The control logic is simple: it is based solely on concentration threshold control and does not quantify the coupling risk between the dynamic trend of leakage and the mechanical state.

[0016] Therefore, corresponding improvements have been made to address the aforementioned issues. SUMMARY

[0017] Based on the technical problems existing in the prior art, the application provides a conical vacuum pump for gas delivery.

[0018] The conical vacuum pump for gas delivery provided by the application comprises a pump body, the pump body is fixedly installed at one end of a motor close to an output shaft, the output shaft of the motor is connected with a rotor located inside the pump body, and the pump body is further provided with an air inlet pipe and an air outlet pipe, and further comprises: a gas leakage monitoring module installed close to the air inlet pipe and the air outlet pipe, used for monitoring methane leakage caused by sealing failure in real time and generating a sealing failure coefficient through a control module; and a bearing state monitoring module installed close to a bearing, used for monitoring abnormal vibration caused by rotor imbalance or friction in real time and generating a mechanical friction coefficient through the control module; the sealing failure coefficient and the mechanical friction coefficient generated are comprehensively analyzed through the control module to generate an evaluation coefficient, whether the current rotating speed needs to be adjusted is judged, the evaluation coefficient is compared with a preset reference threshold value, and the working state of the motor is controlled according to the comparison result.

[0019] Preferably, the rotor adopts a tapered conical design to improve the gas suction efficiency.

[0020] Preferably, an electromagnetic valve is installed in the air inlet pipe to open or close a gas supply air path.

[0021] Preferably, the output end and the input end of the gas leakage monitoring module and the output end and the input end of the bearing state monitoring module are respectively electrically connected with the input end and the output end of the control module, and the output end of the control module is respectively electrically connected with the input end of the motor and the input end of the electromagnetic valve.

[0022] Preferably, the execution steps of the control module for controlling the working state of the motor according to the comparison result are as follows:

[0023] The gas leakage monitoring module collects methane leakage, the bearing state monitoring module collects abnormal vibration, the control module calculates the sealing failure coefficient, the mechanical friction coefficient and the evaluation coefficient, if the evaluation coefficient is less than a first threshold value, the current parameters are maintained, if the evaluation coefficient is greater than or equal to the first threshold value and less than a second threshold value, the rotating speed is reduced, a secondary alarm is triggered, and if the evaluation coefficient is greater than the second threshold value, the motor is immediately stopped, the electromagnetic valve is closed, and the gas supply air path is cut off.

[0024] Preferably, the generation logic of the sealing failure coefficient is as follows:

[0025] Based on the actual methane leakage concentrations at multiple time points collected by the gas leakage monitoring module within a set time period T, the dispersion degree of the concentrations relative to the average concentration within the time period is calculated to generate a sealing failure coefficient quantifying the sealing leakage risk level.

[0026] Preferably, the generation logic of the mechanical friction coefficient is:

[0027] Based on the actual vibration intensity collected by the bearing state monitoring module at multiple moments within a set time period T, the dispersion degree of the vibration intensity relative to the average vibration intensity within the time period is calculated, and the mechanical friction coefficient quantifying the degree of mechanical friction abnormality is generated.

[0028] Preferably, the generation logic of the evaluation coefficient is:

[0029] The control module generates the evaluation coefficient by dynamically weighing and calculating the coupling of the sealing failure coefficient and the mechanical friction coefficient, combined with a preset weight coefficient; wherein the influence weight of the sealing failure coefficient on the evaluation coefficient is greater than the influence weight of the mechanical friction coefficient.

[0030] Compared with the prior art, the present application provides a conical vacuum pump for gas transmission, which has the following beneficial effects:

[0031] 1. A conical vacuum pump for gas transmission, which realizes the graded control of "slight risk speed reduction warning-severe risk shutdown" by monitoring the methane leakage (ppm level precision) and mechanical vibration in real time, quantifying the sealing failure coefficient (Sδ) and the mechanical friction coefficient (Vσ), and dynamically judging the risk level through the evaluation coefficient (Rpg), thereby avoiding the risk of gas explosion caused by the coupling of leakage and mechanical failure from the source (such as the superimposed hazards of high-pressure leakage and mechanical spark).

[0032] 2. A conical vacuum pump for gas transmission, which adopts a tapered conical design for the rotor, utilizes the pumping gain effect of the conical structure to improve the gas pumping efficiency; at the same time, by dynamically adjusting the speed (not necessary to stop), the invalid energy consumption is reduced under the premise of safety, balancing efficiency and safety.

[0033] 3. A conical vacuum pump for gas transmission, which adopts the algorithm of "dispersion degree quantification + dynamic weight coupling" (formal calculation of Sδ, Vσ, Rpg), instead of the traditional single threshold judgment, can capture the dynamic trend of progressive failures such as sealing aging and early bearing wear, realize "early discovery and early regulation", and avoid sudden deterioration of faults.

[0034] 4. A conical vacuum pump for gas transmission, which adopts the integrated design of the monitoring module (laser sensor, three-axis vibration sensor) and the control module (STM32 embedded controller), ensures the real-time data acquisition and fast control response; the linkage of the electromagnetic valve and the shutdown mechanism provides hardware-level safety protection for extreme risks, further improving the reliability of the system in dangerous environments such as gas. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 A first angle structure schematic diagram of a conical vacuum pump for gas delivery according to the present application;

[0036] Figure 2 A second angle structure schematic diagram of a conical vacuum pump for gas delivery according to the present application;

[0037] Figure 3 A system block diagram of a conical vacuum pump for gas delivery according to the present application; Figure 2 An enlarged structure schematic diagram of A according to the present application;

[0038] Figure 4 A system block diagram of a conical vacuum pump for gas delivery according to the present application.

[0039] In the figure: 1, pump body; 2, motor; 3, air inlet pipe; 4, air outlet pipe; 5, gas leakage monitoring module; 6, bearing state monitoring module; 7, control module. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments.

[0041] In the description of the present application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0042] Referring to Figures 1-4 A conical vacuum pump for gas delivery, comprising a pump body 1 fixedly installed at one end of a motor 2 close to an output shaft, the output shaft of the motor 2 being connected with a rotor located inside the pump body 1, the pump body 1 further being provided with an air inlet pipe 3 and an air outlet pipe 4, further comprising:

[0043] A gas leakage monitoring module 5 installed at a position close to the air inlet pipe 3 and the air outlet pipe 4, for monitoring methane leakage caused by sealing failure in real time, and generating a sealing failure coefficient through a control module 7;

[0044] A bearing state monitoring module 6 installed at a position close to a bearing, for monitoring abnormal vibration caused by rotor imbalance or friction in real time, and generating a mechanical friction coefficient through the control module 7;

[0045] It should be noted that the gas leakage monitoring module 5 can be a laser methane sensor (TDLAS type, accuracy up to ppm level) or other devices capable of monitoring methane leakage caused by seal failure in real time, the bearing state monitoring module 6 can be a three-axis vibration sensor or other devices capable of monitoring abnormal vibration caused by rotor imbalance or friction in real time, and the control module 7 is an embedded controller (such as STM32 series) integrated with a data fusion algorithm, so the gas leakage monitoring module 5, the bearing state monitoring module 6 and the control module 7 are not specifically limited here and can be selected according to actual needs.

[0046] In use, the generated seal failure coefficient and mechanical friction coefficient are comprehensively analyzed by the control module 7 to generate an evaluation coefficient, and it is judged whether the current rotating speed needs to be adjusted. The evaluation coefficient is compared with a pre-set reference threshold value, and the working state of the motor 2 is controlled according to the comparison result.

[0047] Further, the rotor adopts a tapered conical design to improve the gas suction efficiency.

[0048] Further, an electromagnetic valve is installed in the gas inlet pipe 3 for opening or closing the gas supply path.

[0049] The output end and the input end of the gas leakage monitoring module 5, the output end and the input end of the bearing state monitoring module 6 are respectively electrically connected with the input end and the output end of the control module 7, and the output end of the control module 7 is respectively electrically connected with the input end of the motor 2 and the input end of the electromagnetic valve.

[0050] In another embodiment, the execution steps of the control module 7 for comprehensively analyzing the generated seal failure coefficient and mechanical friction coefficient to generate an evaluation coefficient, judging whether the current rotating speed needs to be adjusted, comparing the evaluation coefficient with a pre-set reference threshold value, and controlling the working state of the motor 2 according to the comparison result are as follows:

[0051] Real-time detection: the gas leakage monitoring module 5 collects methane leakage; the bearing state monitoring module 6 collects abnormal vibration;

[0052] Coefficient calculation:

[0053] Seal failure coefficient: representing the dispersion degree of methane concentration outside the sealing cavity, quantifying the dynamic change trend of leakage risk; Sδ approaches to 0: indicating that the concentration fluctuation is very small, the seal is perfect, 0

[0054] The generation logic of the seal failure coefficient is as follows:

[0055] S1, the actual leakage concentration of methane at different times within T time when the vacuum pump is working is obtained by the gas leakage monitoring module 5, and the actual leakage concentration obtained at the m-th moment within T time is marked as Cm, m = 1, 2, 3, …, t, m, m = 1, 2, 3, …, t, m is a positive integer;

[0056] S2, the sealing failure coefficient is calculated, and the expression for calculation is:

[0057] In the formula, is the average concentration within T time; t is the sampling number within T time.

[0058] Mechanical friction coefficient: representing the dispersion degree of bearing vibration acceleration, reflecting the abnormal degree of mechanical state of rotating parts; Vσ tends to 0: stable vibration, normal operation of bearing / rotor, no friction or collision; 0 < Vσ < 0.2: slight fluctuation, early bearing wear (such as insufficient lubrication), which needs to be warned; Vσ≥0.2: severe fluctuation, serious mechanical failure → rotor imbalance or dry friction → high temperature / spark → ignition of leaked gas;

[0059] Wherein, the generation logic of the mechanical friction coefficient is:

[0060] S1, the actual vibration intensity at different times within T time when the vacuum pump is working is obtained by the bearing state monitoring module 6, and the actual vibration intensity obtained at the n-th moment within T time is marked as Vn, n = 1, 2, 3, …, k, n is a positive integer;

[0061] S2, the mechanical friction coefficient is calculated, and the expression for calculation is:

[0062] In the formula, is the average vibration intensity within T time; k is the sampling number within T time.

[0063] Evaluation coefficient: quantifying the overall safety risk level of the system, and coupling the coupling effect of leakage risk and mechanical failure; the control module 7 generates the evaluation coefficient by dynamically balancing the sealing failure coefficient and the mechanical friction coefficient and combining the preset weight coefficient, and the formula is analyzed by the control module 7, according to the formula:

[0064] In the formula, r_1 is the weight coefficient (determined dynamically combined with experimental data), r_2 is the weight coefficient (determined dynamically combined with experimental data), r_1 > r_2 > 1.

[0065] Dynamic adjustment: if Rpg < 1.5: maintain the current parameters; if 1.5 ≤ Rpg < 3.0: reduce the speed by 20%, trigger the secondary alarm, if 3.0 ≤ Rpg: immediately stop, close the electromagnetic valve, and cut off the gas supply path.​

[0066] Working principle:

[0067] The working principle of the conical gas delivery vacuum pump mainly includes two parts: basic gas delivery and intelligent monitoring and dynamic regulation, as follows:

[0068] 1. Basic gas delivery process

[0069] The tapered conical rotor in the motor-driven pump body rotates, uses the suction effect of the conical structure, absorbs gas through the gas inlet pipe, compresses it inside the pump body, and then discharges it through the gas outlet pipe, realizing the directional delivery of gas. The electromagnetic valve in the gas inlet pipe can control the on-off of the gas path, providing hardware support for cutting off the gas source in emergency situations.

[0070] 2. Intelligent monitoring and dynamic regulation process

[0071] (1) Real-time monitoring:

[0072] The gas leakage monitoring module (such as TDLAS type laser methane sensor) is installed near the gas inlet and outlet pipes, and real-time acquisition of methane leakage concentration at different times within T time is carried out to capture the leakage dynamics caused by seal failure.

[0073] The bearing state monitoring module (such as three-axis vibration sensor) is installed near the bearing, and real-time acquisition of vibration intensity at different times within T time is carried out to capture abnormal vibration caused by rotor imbalance or friction.

[0074] (2) Coefficient calculation:

[0075] Seal failure coefficient (Sδ): By calculating the dispersion degree of methane leakage concentration within T time (based on the ratio of standard deviation to average value of concentration data), the seal risk is quantified. Sδ tends to 0, indicating that the seal is perfect, 0<Sδ<0.3 for slight leakage, and Sδ≥0.3 for seal failure (high-pressure spattering leakage);

[0076] Mechanical friction coefficient (Vσ): By calculating the dispersion degree of vibration intensity within T time (based on the ratio of standard deviation to average value of vibration data), the mechanical failure risk is quantified. Vσ tends to 0, indicating that the mechanical state is normal, 0<Vσ<0.2 for light wear, and Vσ≥0.2 for serious failure (rotor imbalance or dry friction).

[0077] (3) Evaluation and dynamic regulation:

[0078] The control module calculates the evaluation coefficient by coupling the seal failure coefficient and the mechanical friction coefficient, combined with the weight coefficient (r_1>r_2>1, with higher weight for leakage risk):

[0079] If Rpg<1.5: maintain the current speed, normal operation;

[0080] If 1.5≤Rpg<3.0: reduce the speed by 20%, trigger a secondary alarm (prompt a slight risk);

[0081] If Rpg≥3.0: immediately stop, close the electromagnetic valve to cut off the gas path (to avoid serious accidents such as explosion).

[0082] The above merely describes the preferred embodiments of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can make equivalent replacements or changes within the technical range disclosed by the present application according to the technical solutions and the inventive concept of the present application, which should be covered within the protection scope of the present application.

Claims

1. A conical vacuum pump for gas delivery, comprising a pump body (1), characterized in that, The pump body (1) is fixedly installed at one end of the motor (2) near the output shaft. The output shaft of the motor (2) is connected to a rotor located inside the pump body (1). The pump body (1) is also provided with an air inlet pipe (3) and an air outlet pipe (4), and also includes: The gas leak monitoring module (5) is installed near the inlet pipe (3) and the outlet pipe (4) to monitor methane leaks caused by seal failure in real time. Based on the actual methane leak concentration collected by the gas leak monitoring module (5) at multiple times within a set time period T, the dispersion of the concentration relative to the average concentration within this time period is calculated to generate a seal failure coefficient that quantifies the risk level of seal leaks. The bearing condition monitoring module (6) is installed near the bearing and is used to monitor abnormal vibration caused by rotor imbalance or friction in real time. Based on the actual vibration intensity collected by the bearing condition monitoring module (6) at multiple moments within a set time period T, the dispersion of the vibration intensity relative to the average vibration intensity within that time period is calculated, and a mechanical friction coefficient that quantifies the degree of abnormal mechanical friction is generated. The control module (7) generates an evaluation coefficient by coupling the sealing failure coefficient and the mechanical friction coefficient and performing a dynamic trade-off calculation based on a preset weighting coefficient; wherein, the influence weight of the sealing failure coefficient on the evaluation coefficient is greater than the influence weight of the mechanical friction coefficient. The evaluation coefficient is compared with a preset reference threshold, and the working state of the motor (2) is controlled according to the comparison result. If the evaluation coefficient is less than the first threshold: maintain the current parameters; if the evaluation coefficient is greater than or equal to the first threshold but less than the second threshold: reduce the speed and trigger the second-level alarm; if the evaluation coefficient is greater than the second threshold: stop the machine immediately, close the solenoid valve, and cut off the gas supply.

2. A conical vacuum pump for gas delivery according to claim 1, characterized in that, The rotor adopts a tapered design to improve gas extraction efficiency.

3. A conical vacuum pump for gas transportation according to claim 1, characterized in that, A solenoid valve is installed inside the air intake pipe (3).

4. A conical vacuum pump for gas delivery according to claim 3, characterized in that, The output and input terminals of the gas leak monitoring module (5) and the output and input terminals of the bearing condition monitoring module (6) are electrically connected to the input and output terminals of the control module (7), respectively. The output terminal of the control module (7) is electrically connected to the input terminal of the motor (2) and the input terminal of the solenoid valve, respectively.

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