Collaborative flow rate control method of cooling water and nitrogen gas used for dry pump

Abstract

To provide a collaborative flow rate control method of cooling water and nitrogen gas used for a dry pump.SOLUTION: In a process where a dry pump is used for processing a product, a cooling water flows in a pump body of the dry pump to decrease temperature of the dry pump. When the dry pump is in a condensation state, the cooling water flow rate is decreased while an inner temperature of a pump chamber of the dry pump is increased by purging hot nitrogen gas into the pump chamber of the dry pump. When the dry pump is in an almost critical high-temperature state, the cooling water flow rate is increased while a work temperature of the dry pump is quickly decreased by conveying cold nitrogen gas into the pump chamber of the dry pump. When the dry pump is in a safety state between the condensation state and the high-temperature state, the cooling water flow rate is controlled while the hot nitrogen gas or the cold nitrogen gas is purged into the pump chamber of the dry pump.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the technical field of dry pumps, and more particularly to a method for adjusting the flow rates of cooling water and nitrogen gas used in a dry pump in a coordinated manner. [Background technology]

[0002] Dry pumps are devices that realize vacuum by extracting gas without using oil or other working medium and discharging it directly to the atmosphere. Since the advent of dry pump technology, the way vacuum is generated and applied in industrial production has changed greatly. Dry pumps can be applied to production systems with strict requirements for cleanliness and where corrosive gases, moisture and dust are present, making them the first choice and important equipment in general semiconductor production lines.

[0003] Dry pumps are divided into two types: positive displacement and momentum type, with positive displacement dry pumps being the most widely used. Positive displacement dry pumps are divided into several types, such as claw type, roots type, and screw type, according to the difference in the rotor mold line. During operation, the two rotors in the dry pump rotate and mesh with each other to suck in external gas and then discharge it to the outside. The sucked working gas is compressed and rotates and rubs against the rotors at high speed, causing the temperature inside the pump chamber to reach a level of more than 100 to 200 degrees Celsius, and the adhesion of dust generated by reaction with the sucked working gas further causes friction between the rotors and between the rotor and the pump chamber, leading to jamming.

[0004] For dry pumps used in general-purpose semiconductor production lines, the requirements for the long-term operation stability, reliability, and operability of the dry pumps are particularly high, since they face the possibility of ingested working gases that are toxic, flammable, explosive, and corrosive, while shutdowns due to failures will bring about huge economic losses to the semiconductor production line. In order to reduce shutdowns due to failures of the dry pumps, it is very important to control the temperature rise of the dry pumps and remove dust.

[0005] Dry pumps are generally cooled by water to control the temperature rise. That is, cooling water is fed into the pump housing of the dry pump through piping to directly cool the pump body. Dust is generally removed by feeding nitrogen gas into the pump chamber to purge it. The chemical reaction products of the sucked working gas generate dust at low temperatures, which is likely to contaminate the rotor surface, and water vapor condenses at low temperatures, which is likely to enhance dust adhesion. Therefore, the nitrogen gas used for purging is heated by a heater outside the pump body before being fed into the pump chamber.

[0006] In the conventional dry pump cooling and dust purging technology, the delivery of cooling water and nitrogen gas is controlled independently, and the two are not adjusted in conjunction. The cooling of the dry pump by the cooling water causes a difference in the heat demand of the hot nitrogen gas in the pump chamber, and the import of hot nitrogen gas into the pump chamber also affects the temperature of the dry pump. Therefore, by adjusting the two in conjunction, the cooling water and nitrogen gas can play their roles better and reduce the consumption of materials and energy.

[0007] In addition, after a certain degree of vacuum is formed in the pump chamber of the dry pump, the gas is thin, and the heat dissipation due to gas convection from the wall of the pump chamber of the dry pump to the rotor is greatly reduced, and there is only one heat dissipation path through which the cooling water passes through the housing of the dry pump and conducts heat to the metal on the rotor. At this time, the heat dissipation efficiency of the pump chamber of the dry pump is low, and the temperature reduction speed of the dry pump is relatively slow. Summary of the Invention [Problem to be solved by the invention]

[0008] In order to overcome the shortcomings and deficiencies of the prior art, the object of the present invention is to provide a method for coordinated flow rate adjustment of cooling water and nitrogen gas used in a dry pump, which uses cooling water and nitrogen gas in coordination to adjust temperature and purge dust for a dry pump, thereby more efficiently controlling the operating temperature of the dry pump, reducing the amount of cooling water and nitrogen gas used, reducing the energy consumption required to heat the nitrogen gas, reducing the adhesion of dust in the pump chamber of the dry pump, and reducing the frequency of blowing off dust inside the dry pump, thereby achieving the purpose of reducing the maintenance and repair costs and operating costs of the dry pump. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention is realized by the following technical solution: A method for adjusting the flow rates of cooling water and nitrogen gas used in a dry pump in cooperation with each other, in the process in which the dry pump participates in the processing of a product, the cooling water flows through the pump body of the dry pump to cool the dry pump, when the dry pump is in a condensation state, the flow rate of the cooling water is reduced and hot nitrogen gas is purged into the pump chamber of the dry pump to increase the internal temperature of the pump chamber of the dry pump to avoid condensation, when the dry pump is in a high temperature state close to the critical point, the flow rate of the cooling water is increased and cold nitrogen gas is transported into the pump chamber of the dry pump to purge, so that the working temperature of the dry pump is quickly lowered to a safe temperature range, when the dry pump is in a safe state between the condensation state and the high temperature state, the flow rate of the cooling water is adjusted with the goal of adjusting the working temperature of the dry pump to a target value of the working temperature, and hot or cold nitrogen gas is purged into the pump chamber of the dry pump according to the requirement of the temperature adjustment speed, thereby realizing a temperature control and dust purging mode of the dry pump mainly using cooling water and supplemented with cold / hot nitrogen gas.

[0010] The present invention uses two methods, cooling water and nitrogen gas, in cooperation to regulate the temperature of the dry pump, which can more efficiently control the operating temperature of the dry pump, reduce the amount of cooling water and nitrogen gas used, reduce the energy consumption required to heat the nitrogen gas, save the operating costs of the dry pump, prevent more dust caused by gas condensation from adhering to the walls and rotor of the pump chamber of the dry pump, reduce the frequency of blowing off dust inside the dry pump, and reduce maintenance and repair costs.

[0011] In the present invention, when the rotor is in a high temperature state close to the critical point, in addition to the cooling method using cooling water, cold nitrogen gas is added to directly purge the rotor, so that the nitrogen gas can carry away the heat of the rotor, thereby improving the heat dissipation effect.

[0012] Preferably, in the process in which the dry pump participates in the processing of the product, the method for adjusting the flow rate of the cooling water and the nitrogen gas in cooperation with each other includes: Step S1: setting a target operating temperature and a condensation temperature, the target operating temperature being greater than the upper limit of a temperature range with a high dust generation rate and less than the upper limit of a safe operating temperature of the dry pump, the condensation temperature being greater than the upper limit of a temperature range where condensation is likely to occur and less than the target operating temperature, and initializing the flow rate of the cooling water; A step S2 of detecting a temperature of an internal region of a pump chamber of the dry pump in real time to obtain a maximum temperature region and a minimum temperature region of the internal region of the pump chamber of the dry pump; Determine the condition of the dry pump, Step S3: if the temperature of the lowest temperature region is equal to or lower than the condensation temperature, it is determined that the dry pump is in a condensation state; if the difference between the upper limit of the safe operating temperature and the temperature of the highest temperature region is smaller than a set safe difference, it is determined that the dry pump is in a high temperature state close to a critical temperature; otherwise, it is determined that the dry pump is in a safe state; A cooling amount required for lowering the temperature is obtained based on a difference between the temperature of the maximum temperature region and the target operating temperature value. When the dry pump is in a condensing state, the flow rate of the cooling water is reduced according to the amount of cooling required to lower the temperature, the cold / hot type of nitrogen gas is set as hot nitrogen gas, and hot nitrogen gas is purged into the pump chamber of the dry pump to increase the internal temperature of the pump chamber of the dry pump; When the dry pump is in a high-temperature state close to the critical point, the flow rate of the cooling water is increased to the maximum, the nitrogen gas cold / hot type is set as cold nitrogen gas, and cold nitrogen gas is transported into the pump chamber of the dry pump to purge it, thereby quickly lowering the operating temperature of the dry pump to a safe temperature range. and step S4, when the dry pump is in a safe state, adjusting the flow rate of cooling water according to the amount of cooling required to lower the temperature, setting the cold / hot type of nitrogen gas as cold nitrogen gas or hot nitrogen gas, and transporting cold nitrogen gas or hot nitrogen gas into the pump chamber of the dry pump to purge dust.

[0013] Preferably, when the dry pump is in a condensing state, the flow rate of the hot nitrogen gas is set as the maximum flow rate of the allowable range of the working nitrogen gas of the dry pump, or the flow rate of the hot nitrogen gas is set according to the difference between the condensing temperature and the lowest temperature region; When the dry pump is in a high temperature state close to the critical point, the flow rate of the cold nitrogen gas is set as the maximum flow rate of the operating nitrogen gas of the dry pump; When the dry pump is in a safe state, the flow rate of cold or hot nitrogen gas is set as the flow rate of nitrogen gas required to purge the dust.

[0014] Preferably, the flow rate of hot nitrogen gas when the dry pump is in a condensing state > the flow rate of cold or hot nitrogen gas when the dry pump is in a safe state, and the flow rate of cold nitrogen gas when the dry pump is in a high temperature state near critical > the flow rate of cold or hot nitrogen gas when the dry pump is in a safe state.

[0015] Preferably, when the dry pump is in a safe state, according to the requirement for temperature adjustment speed, the setting method for the cold and hot type of nitrogen gas is as follows: A first solution for setting an early warning value, and when the maximum temperature range is equal to or greater than the early warning value, setting the cold type of nitrogen gas as cold nitrogen gas, and when the maximum temperature range is less than the early warning value, setting the cold type of nitrogen gas as hot nitrogen gas; and a second solution for setting the cold or hot type of nitrogen gas as hot nitrogen gas.

[0016] Preferably, in step S2, the method for detecting the temperature of the internal region of the pump chamber of the dry pump in real time is to detect the temperature in real time by one or more contact temperature sensing modules attached to the pump body of the dry pump, or to obtain a thermal image distribution map by a non-contact infrared thermography device. The non-contact infrared thermography device does not need to drill holes in the pump body of the dry pump, can reflect the entire temperature and its distribution of the dry pump, and is not affected by the vibration of the dry pump.

[0017] Preferably, a high dust production rate temperature zone of the working gas sucked into the dry pump is obtained according to the type and concentration of the working gas sucked into the dry pump, and a target operating temperature value is set, thereby bringing the operating temperature of the dry pump into a non-high dust production rate temperature zone, thereby reducing the production of dust in the pump chamber of the dry pump, and a condensation temperature is set according to the type and concentration of the working gas sucked into the dry pump.

[0018] By target-orientedly setting the operating temperature target value and the condensation temperature according to the type and concentration of the working gas sucked into the dry pump, the generation and adhesion of dust in the pump chamber of the dry pump can be further reduced.

[0019] Preferably, a heating branch pipeline and a cooling branch pipeline are connected in parallel to the nitrogen gas transport pipeline, and the nitrogen gas transport pipeline and the heating branch pipeline are connected by a switch module to heat the nitrogen gas to obtain hot nitrogen gas, or the nitrogen gas transport pipeline and the cooling branch pipeline are connected to lower the temperature of the nitrogen gas to obtain cold nitrogen gas.

[0020] Preferably, the heating branch line heats the nitrogen gas by an electric heating device.

[0021] Preferably, the cooling branch pipe lowers the temperature of the nitrogen gas with cooling water. Effect of the Invention

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects: First, the present invention adjusts the temperature of the dry pump by using two methods, cooling water and nitrogen gas, in cooperation with each other, to more efficiently control the operating temperature of the dry pump, reduce the amount of cooling water and nitrogen gas used, reduce the energy consumption required to heat the nitrogen gas, and save the operating cost of the dry pump. Secondly, when the dry pump is in a condensing state, the present invention reduces the flow rate of the cooling water and purges hot nitrogen gas into the pump chamber of the dry pump to increase the internal temperature of the pump chamber of the dry pump, thereby preventing more dust from adhering to the walls and rotor of the pump chamber of the dry pump due to condensation of the gas, reducing the frequency of blowing off the dust inside the dry pump and reducing maintenance and repair costs. Third, when the dry pump is in a high-temperature state close to the critical point, the present invention increases the amount of cold nitrogen gas to directly purge the rotor, allowing the nitrogen gas to carry away the heat of the rotor, improving the heat dissipation effect. Fourth, the present invention can maintain the internal temperature of the pump chamber of the dry pump within a range approximately close to the target operating temperature value, and by setting the target operating temperature value outside the temperature range with high dust generation rates, it is possible to reduce the generation of dust in the pump chamber of the dry pump. By target-oriented setting the target operating temperature value and the condensation temperature according to the type and concentration of the working gas sucked into the dry pump, it is possible to further reduce the generation and adhesion of dust in the pump chamber of the dry pump. [Brief description of the drawings]

[0023] [Figure 1] 4 is a flowchart of a method for adjusting the flow rates of cooling water and nitrogen gas in cooperation with each other for use in a dry pump according to the present invention. [Diagram 2] 1 is a schematic diagram of a nitrogen gas transport pipe in a method for adjusting the flow rates of cooling water and nitrogen gas in coordination with each other, which is used in a dry pump according to the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The present invention will be described in more detail below with reference to specific embodiments with reference to the drawings.

[0025] Working Example In the method for adjusting the flow rates of cooling water and nitrogen gas used in the dry pump according to the present embodiment, during the process in which the dry pump participates in the processing of a product, cooling water flows through the pump body of the dry pump to cool the dry pump; when the dry pump is in a condensation state, the flow rate of cooling water is reduced and hot nitrogen gas is purged into the pump chamber of the dry pump to increase the internal temperature of the pump chamber of the dry pump to avoid condensation; when the dry pump is in a high-temperature state close to the critical point, the flow rate of cooling water is increased and cold nitrogen gas is transported into the pump chamber of the dry pump for purging, thereby quickly lowering the operating temperature of the dry pump to a safe temperature range; when the dry pump is in a safe state between the condensation state and the high-temperature state, the flow rate of cooling water is adjusted with the goal of adjusting the operating temperature of the dry pump to the target operating temperature value, and hot or cold nitrogen gas is purged into the pump chamber of the dry pump according to the requirement for the temperature adjustment speed, thereby realizing a temperature control and dust purging mode of the dry pump mainly using cooling water and auxiliary cold / hot nitrogen gas.

[0026] Specifically, in the process of the dry pump participating in the processing of the product, the method for adjusting the flow rate of the cooling water and the nitrogen gas in coordination is shown in FIG. 1 and includes the following steps:

[0027] S1 Setting an operating temperature target value and a condensation temperature, the method of setting the operating temperature target value and the condensation temperature includes obtaining a high dust production rate temperature zone of the working gas sucked into the dry pump in accordance with the type and concentration of the working gas sucked into the dry pump, and further setting an operating temperature target value to bring the operating temperature of the dry pump into a non-high dust production rate temperature zone, thereby reducing the production of dust in the pump chamber of the dry pump, and setting a condensation temperature in accordance with the type and concentration of the working gas sucked into the dry pump.

[0028] The target working temperature and the condensation temperature change according to the type and concentration of the working gas sucked into the dry pump, and the corresponding relationship between the type and concentration of the working gas sucked into the dry pump and the target working temperature and the condensation temperature can be established in the conventional manner, for example, in the operation process of the dry pump, a limited number of tests are performed using different types and concentrations of sucked working gas, and in the test process, the high dust generation rate temperature zone and the temperature zone where the condensation phenomenon is likely to occur for each of the different types and concentrations of sucked working gas are recorded, and then the target working temperature and the condensation temperature are respectively set for the different types and concentrations of sucked working gas, and the target working temperature is greater than the upper limit of the high dust generation rate temperature zone and is less than the upper limit of the safe operating temperature of the dry pump, and the condensation temperature is greater than the upper limit of the temperature zone where the condensation phenomenon is likely to occur and is less than the target working temperature. In this way, a table of the corresponding relationship between the type and concentration of the sucked working gas and the target working temperature and the condensation temperature can be created, and then the corresponding relationship between the type and concentration of the working gas sucked into the dry pump and the target working temperature and the condensation temperature can be obtained by a table lookup method.

[0029] Initialize the cooling water flow rate, S2 Detect the temperature of the internal region of the pump chamber of the dry pump in real time by one or more contact temperature sensing modules attached to the pump body of the dry pump, or detect the temperature of the dry pump in real time by obtaining a thermal image distribution map by a non-contact infrared thermography device, and obtain the maximum temperature region and the minimum temperature region of the internal region of the pump chamber of the dry pump.

[0030] S3 Determine the status of the dry pump and If the temperature of the lowest temperature region is below the condensation temperature, the dry pump is determined to be in a condensing state; if the difference between the upper limit of the safe operating temperature and the temperature of the highest temperature region is smaller than a set safe difference, the dry pump is determined to be in a high temperature state close to critical; otherwise, the dry pump is determined to be in a safe state.

[0031] S4: Obtaining the amount of cooling required to lower the temperature based on the difference between the temperature of the maximum temperature region and the target operating temperature value; When the dry pump is in a condensing state, the flow rate of the cooling water is reduced according to the amount of cooling required to lower the temperature, the cold / hot type of nitrogen gas is set as hot nitrogen gas, and hot nitrogen gas is purged into the pump chamber of the dry pump to increase the internal temperature of the pump chamber of the dry pump; When the dry pump is in a high-temperature state close to the critical point, the flow rate of the cooling water is increased to the maximum, the nitrogen gas cold / hot type is set as cold nitrogen gas, and cold nitrogen gas is transported into the pump chamber of the dry pump to purge it, thereby quickly lowering the operating temperature of the dry pump to a safe temperature range. When the dry pump is in a safe state, the flow rate of the cooling water is adjusted according to the amount of cooling required to lower the temperature, the cold / hot type of nitrogen gas is set as cold nitrogen gas or hot nitrogen gas, and cold nitrogen gas or hot nitrogen gas is delivered into the pump chamber of the dry pump to purge dust.

[0032] In addition, when the dry pump is in a safe state, according to the requirements for temperature adjustment speed, the setting method for the cold and hot types of nitrogen gas is as follows: For example, when the requirement for temperature adjustment speed is high, an early warning value is set, and when the maximum temperature range ≧ the early warning value, the cold and hot type of nitrogen gas is set as cold nitrogen gas, and when the maximum temperature range < the early warning value, the cold and hot type of nitrogen gas is set as hot nitrogen gas; When the requirement for the temperature adjustment speed is low, the second solution is adopted, which sets the cold type of nitrogen gas as hot nitrogen gas.

[0033] The flow rate of cold or hot nitrogen gas is set as the flow rate of nitrogen gas required to purge the dust.

[0034] When the dry pump is in a condensing state, the demand for hot nitrogen gas is large, and therefore the flow rate of hot nitrogen gas is set as the maximum flow rate of the working nitrogen gas of the dry pump, or the flow rate of hot nitrogen gas is set according to the difference between the condensing temperature and the minimum temperature region.When the dry pump is in a high temperature state close to the critical point, the demand for cold nitrogen gas is large, and therefore the flow rate of cold nitrogen gas is set as the maximum flow rate of the working nitrogen gas of the dry pump.When the dry pump is in a safe state, it is sufficient for cold nitrogen gas or hot nitrogen gas to satisfy the purging of dust, and therefore the flow rate of cold nitrogen gas or hot nitrogen gas is set as the flow rate of nitrogen gas required for purging of dust.

[0035] The flow rate of hot nitrogen gas when the dry pump is in a condensing state > the flow rate of cold or hot nitrogen gas when the dry pump is in a safe state, and the flow rate of cold nitrogen gas when the dry pump is in a high temperature state near critical > the flow rate of cold or hot nitrogen gas when the dry pump is in a safe state.

[0036] As shown in FIG. 2, in this embodiment, a heating branch pipeline 2 and a cooling branch pipeline 3 are connected in parallel to a nitrogen gas transport pipeline 1. An electric heating device is fitted on the outside of the heating branch pipeline 2, and a cooling cover is fitted on the outside of the cooling branch pipeline 3, through which cooling water is passed.

[0037] The switch module 4, for example, a solenoid valve, connects the nitrogen gas transport pipeline 1 and the heating branch pipeline 2 to heat the nitrogen gas to obtain hot nitrogen gas, or connects the nitrogen gas transport pipeline 1 and the cooling branch pipeline 3 to lower the temperature of the nitrogen gas to obtain cold nitrogen gas.

[0038] The rear sides of the heating branch pipe 2 and the cooling branch pipe 3 join together to form a single pipe, which then communicates with the pump chamber of the dry pump.

[0039] The above examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above examples. Any other changes, modifications, substitutions, combinations, and simplifications made without departing from the spirit / essence and principles of the present invention are all equivalent replacement methods and fall within the protection scope of the present invention.

Claims

1. A method for adjusting the flow rates of cooling water and nitrogen gas used in a dry pump in cooperation with each other, comprising the steps of: During the process of the dry pump participating in the processing of products, cooling water flows through the pump body of the dry pump to cool the dry pump; when the dry pump is in a condensation state, the flow rate of the cooling water is reduced and hot nitrogen gas is purged into the pump chamber of the dry pump to increase the internal temperature of the pump chamber of the dry pump, thereby avoiding the occurrence of condensation; when the dry pump is in a high temperature state close to the critical point, the flow rate of the cooling water is increased and cold nitrogen gas is transported into the pump chamber of the dry pump for purging, thereby quickly lowering the working temperature of the dry pump to a safe temperature range; when the dry pump is in a safe state between the condensation state and the high temperature state, the flow rate of the cooling water is adjusted with the goal of adjusting the working temperature of the dry pump to the working temperature target value, and hot or cold nitrogen gas is purged into the pump chamber of the dry pump according to the requirements for the temperature adjustment speed, thereby realizing a temperature control and dust purging mode of the dry pump mainly using cooling water and auxiliary cold / hot nitrogen gas; When dry pumps are used in the processing of products, the flow rate of cooling water and nitrogen gas can be adjusted in coordination as follows: Step S1: setting a target operating temperature and a condensation temperature, the target operating temperature being greater than an upper limit of a temperature range with a high dust generation rate and less than an upper limit of a safe operating temperature of the dry pump, the condensation temperature being greater than an upper limit of a temperature range where condensation is likely to occur and less than the target operating temperature, and initializing a flow rate of cooling water; A step S2 of detecting the temperature of an internal region of a pump chamber of the dry pump in real time to obtain a maximum temperature region and a minimum temperature region of the internal region of the pump chamber of the dry pump; Determine the condition of the dry pump, Step S3: if the temperature of the lowest temperature region is equal to or lower than the condensation temperature, it is determined that the dry pump is in a condensation state; if the difference between the upper limit of the safe operating temperature and the temperature of the highest temperature region is smaller than a set safe difference, it is determined that the dry pump is in a high temperature state close to a critical temperature; otherwise, it is determined that the dry pump is in a safe state; A cooling amount required for lowering the temperature is obtained based on a difference between the temperature of the maximum temperature region and the target operating temperature value. When the dry pump is in a condensing state, the flow rate of the cooling water is reduced according to the amount of cooling required to lower the temperature, the cold / hot type of nitrogen gas is set as hot nitrogen gas, and hot nitrogen gas is purged into the pump chamber of the dry pump to increase the internal temperature of the pump chamber of the dry pump; When the dry pump is in a high-temperature state close to the critical point, the flow rate of the cooling water is increased to the maximum, the nitrogen gas cold / hot type is set as cold nitrogen gas, and cold nitrogen gas is transported into the pump chamber of the dry pump to purge it, thereby quickly lowering the operating temperature of the dry pump to a safe temperature range. and when the dry pump is in a safe state, adjusting the flow rate of the cooling water according to the amount of cooling required to lower the temperature, setting the cold / hot type of the nitrogen gas as cold nitrogen gas or hot nitrogen gas, and transporting the cold nitrogen gas or hot nitrogen gas into the pump chamber of the dry pump to purge dust, comprising: a step S4.

2. When the dry pump is in a condensing state, the flow rate of the hot nitrogen gas is set as the maximum flow rate of the working nitrogen gas of the dry pump, or the flow rate of the hot nitrogen gas is set according to the difference between the condensing temperature and the lowest temperature region; When the dry pump is in a high temperature state close to the critical point, the flow rate of the cold nitrogen gas is set as the maximum flow rate of the operating nitrogen gas of the dry pump; The method for adjusting the coordinated flow rates of cooling water and nitrogen gas used in a dry pump as described in claim 1, characterized in that when the dry pump is in a safe state, the flow rate of cold nitrogen gas or hot nitrogen gas is set as the flow rate of nitrogen gas required for purging dust.

3. The method for adjusting the coordinated flow rates of cooling water and nitrogen gas used in a dry pump as described in claim 2, characterized in that the flow rate of hot nitrogen gas when the dry pump is in a condensing state > the flow rate of cold nitrogen gas or hot nitrogen gas when the dry pump is in a safe state, and the flow rate of cold nitrogen gas when the dry pump is in a high temperature state close to critical > the flow rate of cold nitrogen gas or hot nitrogen gas when the dry pump is in a safe state.

4. When the dry pump is in a safe state, according to the requirements for temperature adjustment speed, the setting method for the cold and hot type of nitrogen gas is as follows: A first solution for solving the problem is to set an early warning value, and when the maximum temperature range is equal to or greater than the early warning value, set the cold type of nitrogen gas as cold nitrogen gas, and when the maximum temperature range is less than the early warning value, set the cold type of nitrogen gas as hot nitrogen gas; and The method for adjusting the coordinated flow rates of cooling water and nitrogen gas used in a dry pump as described in claim 1, characterized in that one of the following solutions is adopted: a first solution means for setting the cold or hot type of nitrogen gas as hot nitrogen gas; and a second solution means for setting the cold or hot type of nitrogen gas as hot nitrogen gas.

5. The method for coordinated flow rate adjustment of cooling water and nitrogen gas used in a dry pump described in any one of claims 1 to 4, characterized in that in step S2, the method for detecting the temperature of the internal region of the pump chamber of the dry pump in real time is to detect it in real time using one or more contact-type temperature sensing modules attached to the pump body of the dry pump, or to detect it in real time by obtaining a thermal image distribution map using a non-contact infrared thermography device.

6. A method for coordinated flow rate adjustment of cooling water and nitrogen gas used in a dry pump as described in claim 1, characterized in that a high dust generation rate temperature zone of the working gas sucked into the dry pump is obtained according to the type and concentration of the working gas sucked into the dry pump, and a target operating temperature value is set, thereby reducing the generation of dust in the pump chamber of the dry pump by making the operating temperature of the dry pump a non-high dust generation rate temperature zone, and a condensation temperature is set according to the type and concentration of the working gas sucked into the dry pump.

7. 2. The method for controlling the coordinated flow rates of cooling water and nitrogen gas used in a dry pump according to claim 1, characterized in that a heating branch pipeline and a cooling branch pipeline connected in parallel are connected to the nitrogen gas transport pipeline, and the nitrogen gas is heated by connecting the nitrogen gas transport pipeline and the heating branch pipeline via a switch module to obtain hot nitrogen gas, or the nitrogen gas is cooled by connecting the nitrogen gas transport pipeline and the cooling branch pipeline to obtain cold nitrogen gas.

8. 8. The method for adjusting the flow rates of cooling water and nitrogen gas in a dry pump in cooperation with each other according to claim 7, wherein the heating branch pipe heats the nitrogen gas by an electric heating device.

9. 8. The method for adjusting the flow rates of cooling water and nitrogen gas in cooperation with each other in a dry pump according to claim 7, wherein the cooling branch pipe lowers the temperature of the nitrogen gas with cooling water.

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