Durable fireproof vacuum pump set system

Abstract

The utility model relates to a durable fireproof vacuum pump set system which comprises a roots pump, a slide valve pump and an oil mist filter. The first helium branch is connected to the oil return node from the helium inlet pipe, the second helium branch is connected to the first vacuum air inlet from the helium inlet pipe, the third helium branch is connected to the helium inlet from the helium inlet pipe, and a normally-closed first stop valve is arranged on the first helium branch; the second helium branch is provided with a first coaxial valve, the third helium branch is sequentially provided with a second coaxial valve, a flow switch and a needle valve, and the flow switch is used for controlling the opening degree of the needle valve. According to the utility model, helium is introduced to a plurality of positions of the vacuum pump set, so that the purging and cleaning effects are achieved, the concentration of discharged hydrogen can be reduced, and the production safety is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of air extraction systems, in particular to a durable and fireproof vacuum pump system. Background Art

[0002] During the production process of a vacuum carburizing oil quenching furnace, carbon and hydrogen are generated. The vacuum pump unit draws carbon into the pump cavity during evacuation, shortening the pump's service life. Hydrogen is also extracted by the vacuum pump and discharged into the atmosphere as waste gas. However, hydrogen is flammable and will ignite when exposed to open flames at a certain concentration. These two issues pose a risk to production.

[0003] Chinese patent CN109163859A discloses an automated device and method for rapidly testing product leaks. This device utilizes a vacuum pump assembly consisting of a Roots pump and a sliding valve pump for vacuuming. However, the device's purpose is simply to test product leaks, with helium used as a leak detection gas. The aforementioned safety issues are not present.

[0004] Therefore, it is necessary to design a durable and fireproof vacuum pump system to solve the above problems. Utility Model Content

[0005] The main purpose of the utility model is to provide a durable and fireproof vacuum pump group system. By passing helium to multiple positions of the vacuum pump group, it can not only play a purging and cleaning role, but also dilute the concentration of discharged hydrogen to ensure production safety.

[0006] The utility model achieves the above-mentioned object through the following technical solutions: a durable and fireproof vacuum pump group system, comprising a main line and a vacuum valve, a Roots pump, a slide valve pump and an oil mist filter arranged in sequence along the main line, the Roots pump having a first vacuum air inlet, a first vacuum air outlet and a first oil return port, the slide valve pump having a second vacuum air inlet, a helium air inlet, an oil extraction port and a second vacuum air outlet, the oil mist filter having a third vacuum air inlet, a third vacuum air outlet and a second oil return port, the main line passing through the first vacuum air inlet, the first vacuum air outlet, the second vacuum air inlet, the second vacuum air outlet, the third vacuum air inlet and the third vacuum air outlet in sequence, an oil return node being between the first vacuum air outlet and the second vacuum air inlet, and the first oil return port and the second oil return port being both connected to the oil return node;

[0007] It also includes a helium inlet pipe, a first helium branch connected from the helium inlet pipe to the oil return node, a second helium branch connected from the helium inlet pipe to the first vacuum inlet, and a third helium branch connected from the helium inlet pipe to the helium inlet. A normally closed first stop valve is provided on the first helium branch, a first coaxial valve is provided on the second helium branch, and a second coaxial valve, a flow switch and a needle valve are provided on the third helium branch in sequence. The flow switch is used to control the opening of the needle valve.

[0008] Specifically, a second pressure gauge is provided on the third helium branch.

[0009] Specifically, a fourth helium branch is connected from the helium inlet pipe to the helium inlet port, and a normally closed second manual valve is provided on the fourth helium branch.

[0010] Specifically, the oil extraction port is connected back to the first vacuum air inlet through an oil pump circuit. An oil pump and a temperature sensor are sequentially provided on the oil pump circuit. The oil pump and the temperature sensor are connected by a hose. The temperature sensor controls the speed of the oil pump according to the oil temperature in the oil pump circuit.

[0011] Furthermore, a first pressure gauge is provided on the oil pump circuit.

[0012] Furthermore, the oil pump is connected in parallel with a check valve that allows oil to flow only from the oil extraction port to the first vacuum air inlet.

[0013] Specifically, the Roots pump further has an oil discharge port.

[0014] Specifically, an air rupture pipe is connected between the first vacuum air inlet and the third vacuum air outlet, and a normally closed air rupture valve is provided on the air rupture pipe.

[0015] The beneficial effects of the technical solution of this utility model are:

[0016] In the present utility model, the first helium branch is used to purge the oil in the vacuum tube between the first vacuum outlet and the second vacuum inlet, and the first stop valve needs to be opened manually according to the working conditions. The second helium branch is controlled on and off by the first coaxial valve, and is used to purge the carbon residue and oil in the Roots pump. It can also dilute the hydrogen concentration to ensure work safety and service life. The third hydrogen branch is controlled on and off by the second coaxial valve, and is used to dilute the hydrogen concentration in the exhaust of the main line. The flow switch is used to monitor the helium flow in the third hydrogen branch. If the flow is low, the opening of the needle valve will be increased, and at the same time, it will play a gas shock role to ensure the oil quality of the sliding valve pump. The utility model not only plays a purging and cleaning role by passing helium to multiple positions of the vacuum pump group, but also can dilute the exhaust hydrogen concentration to ensure production safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 2 is a piping diagram of the vacuum pump system of the embodiment.

[0018] The numbers in the figure represent:

[0019] 1- Main road,

[0020] 2- Vacuum valve;

[0021] 3-Roots pump, 31-first vacuum inlet, 32-first vacuum outlet, 33-first oil return port, 34-oil drain valve;

[0022] 4- slide valve pump, 41- second vacuum inlet, 42- helium inlet, 43- oil extraction port, 44- second vacuum outlet;

[0023] 5- oil mist filter, 51- third vacuum air inlet, 52- third vacuum air outlet, 53- second oil return port;

[0024] 6- oil pump circuit, 61- oil pump, 62- first pressure gauge, 63- temperature sensor, 64- hose, 65- check valve;

[0025] 7 - helium inlet pipe, 71 - first helium branch, 711 - first manual valve, 72 - second helium branch, 721 - first coaxial valve, 73 - third helium branch, 731 - second coaxial valve, 732 - flow switch, 733 - needle valve, 734 - second pressure gauge, 74 - fourth helium branch, 741 - second manual valve;

[0026] 8-air-breaking pipe, 81-air-breaking valve. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below with reference to specific embodiments.

[0028] Example:

[0029] like Figure 1 As shown, the durable and fireproof vacuum pump system of the present invention includes a main line 1 and a vacuum valve 2, a Roots pump 3, a slide valve pump 4 and an oil mist filter 5 arranged in sequence along the main line 1.

[0030] like Figure 1As shown, the Roots pump 3 has a first vacuum inlet 31, a first vacuum outlet 32, a first oil return port 33, and an oil drain port 34. The slide valve pump 4 has a second vacuum inlet 41, a helium inlet 42, an oil extraction port 43, and a second vacuum outlet 44. The oil mist filter 5 has a third vacuum inlet 51, a third vacuum outlet 52, and a second oil return port 53. The main line 1 passes through the first vacuum inlet 31, the first vacuum outlet 32, the second vacuum inlet 41, the second vacuum outlet 44, the third vacuum inlet 51, and the third vacuum outlet 52 in sequence. The oil return node is between the first vacuum outlet 32 ​​and the second vacuum inlet 41, and the first oil return port 33 and the second oil return port 53 are both connected to the oil return node.

[0031] The main line 1 is the primary route for extracting gas. The Roots pump 3 and the slide valve pump 4 are both driven by oil pressure and work together to create a vacuum. Oil overflowing from the first return port 33 of the Roots pump 3 is sent to the second vacuum inlet 41. The oil mist filter 5 intercepts a small amount of oil mist and also returns it to the second vacuum inlet 41, keeping the oil within the system as much as possible and minimizing exhaust losses. The oil drain port 34 is used to remove used oil from the Roots pump 3.

[0032] like Figure 1 As shown, the oil extraction port 43 is connected back to the first vacuum air inlet 31 through the oil pump circuit 6. The oil pump circuit 6 is sequentially equipped with an oil pump 61, a first pressure gauge 62, and a temperature sensor 63. The oil pump 61 and the temperature sensor 63 are connected by a hose 64. The temperature sensor 63 controls the speed of the oil pump 61 based on the oil temperature in the oil pump circuit 6. A check valve 65 is connected in parallel with the oil pump 61 to prevent oil from flowing only from the oil extraction port 43 to the first vacuum air inlet 31.

[0033] The Roots pump 3, the spool pump 4, and the oil pump 61 form a vacuum pump assembly. As the oil circulates through the Roots pump 3 and the spool pump 4, it is primarily pumped back to the first vacuum inlet 31 by the oil pump 61. This cleans the cavity of the Roots pump 3 and effectively extends the service life of the vacuum pump assembly. A temperature sensor 63 detects the temperature of this cleaning oil. If the temperature exceeds a set value, the speed of the oil pump 61 increases, accelerating its flow rate within the hose 64 and thus dissipating heat. If the oil pump 61 shuts down, the oil can still be returned from the spool pump 4 to the Roots pump 3 through the check valve 65, preventing the spool pump 4 from over-pressurizing and causing a dangerous situation. The first pressure gauge 62 indicates the pressure in the oil pump circuit 6, alerting workers to take emergency measures if the pressure is too high. By introducing helium gas to multiple locations in the vacuum pump assembly, the present invention not only performs a purging and cleaning function but also dilutes the concentration of hydrogen emissions, ensuring production safety.

[0034] like Figure 1 As shown, an air rupture pipe 8 is connected between the first vacuum air inlet 31 and the third vacuum air outlet 52 , and a normally closed air rupture valve 81 is provided on the air rupture pipe 8 .

[0035] Under normal vacuuming conditions, the rupture valve 81 remains closed. If the pressure upstream of the main line 1 is high, the pressure can be released directly by opening the rupture valve 81 without passing through the vacuum pump group.

[0036] like Figure 1 As shown, the vacuum pump group system also includes a helium inlet pipe 7, a first helium branch 71 connected from the helium inlet pipe 7 to the oil return node, a second helium branch 72 connected from the helium inlet pipe 7 to the first vacuum inlet port 31, and a third helium branch 73 and a fourth helium branch 74 connected from the helium inlet pipe 7 to the helium inlet port 42. The first helium branch 71 is provided with a normally closed first stop valve 711, the second helium branch 72 is provided with a first coaxial valve 721, the third helium branch 73 is provided with a second coaxial valve 731, a flow switch 732, a needle valve 734 and a second pressure gauge 734 in sequence, the flow switch 732 is used to control the opening of the needle valve 733, and the fourth helium branch 74 is provided with a normally closed second manual valve 741.

[0037] The first helium branch 71 is used to purge the oil in the vacuum line between the first vacuum outlet 32 ​​and the second vacuum inlet 41. The first shut-off valve 711 needs to be manually opened depending on the operating conditions. The second helium branch 72, controlled by the first coaxial valve 721, is used to purge carbon residue and oil from the Roots pump 3. It also dilutes the hydrogen concentration, ensuring operational safety and longevity. The third hydrogen branch 73, controlled by the second coaxial valve 731, is used to dilute the hydrogen concentration in the exhaust of the main line 1. The flow switch 732 monitors the helium flow in the third hydrogen branch 73. Low flow increases the opening of the needle valve 733. If the helium flow rate consistently fails to reach the set value, the second manual valve 741 must be opened urgently to reduce the hydrogen concentration, improving safety and reliability. This also acts as a gas shock to ensure the oil quality of the slide valve pump 4. The second pressure gauge 734 indicates the air pressure in the third hydrogen branch 73. If the pressure exceeds the set value, workers are alerted to take emergency measures.

[0038] The above descriptions are only some embodiments of the present invention. For those skilled in the art, several modifications and improvements can be made without departing from the inventive concept of the present invention, and these all fall within the scope of protection of the present invention.

Claims

1. A durable and fireproof vacuum pump system, comprising a main line and a vacuum valve, a Roots pump, a sliding valve pump, and an oil mist filter sequentially arranged along the main line, the Roots pump having a first vacuum inlet, a first vacuum outlet, and a first oil return port, the sliding valve pump having a second vacuum inlet, a helium inlet, an oil extraction port, and a second vacuum outlet, the oil mist filter having a third vacuum inlet, a third vacuum outlet, and a second oil return port, the main line sequentially passing through the first vacuum inlet, the first vacuum outlet, the second vacuum inlet, the second vacuum outlet, the third vacuum inlet, and the third vacuum outlet, an oil return node being between the first vacuum outlet and the second vacuum inlet, and the first oil return port and the second oil return port being both connected to the oil return node; characterized in that: It also includes a helium inlet pipe, a first helium branch connected from the helium inlet pipe to the oil return node, a second helium branch connected from the helium inlet pipe to the first vacuum inlet, and a third helium branch connected from the helium inlet pipe to the helium inlet. A normally closed first stop valve is provided on the first helium branch, a first coaxial valve is provided on the second helium branch, and a second coaxial valve, a flow switch and a needle valve are provided on the third helium branch in sequence. The flow switch is used to control the opening of the needle valve.

2. The durable and fireproof vacuum pump system according to claim 1, characterized in that: A second pressure gauge is provided on the third helium branch.

3. The durable and fireproof vacuum pump system according to claim 1, characterized in that: A fourth helium branch is connected from the helium inlet pipe to the helium inlet port, and a normally closed second manual valve is provided on the fourth helium branch.

4. The durable and fireproof vacuum pump system according to claim 1, characterized in that: The oil extraction port is connected back to the first vacuum air inlet through an oil pump circuit. An oil pump and a temperature sensor are sequentially provided on the oil pump circuit. The oil pump and the temperature sensor are connected by a hose. The temperature sensor controls the speed of the oil pump according to the oil temperature in the oil pump circuit.

5. The durable and fireproof vacuum pump system according to claim 4, characterized in that: A first pressure gauge is provided on the oil pump circuit.

6. The durable and fireproof vacuum pump system according to claim 4, characterized in that: The oil pump is connected in parallel with a check valve that allows oil to flow only from the oil extraction port to the first vacuum air inlet.

7. The durable and fireproof vacuum pump system according to claim 1, characterized in that: The Roots pump also has an oil discharge port.

8. The durable and fireproof vacuum pump system according to claim 1, characterized in that: An air rupture pipe is connected between the first vacuum air inlet and the third vacuum air outlet, and a normally closed air rupture valve is provided on the air rupture pipe.

Images