Carbon potential gas supply system and gas supply method for bearing heat treatment

Abstract

The invention belongs to the technical field of bearing heat treatment, and particularly relates to a carbon potential gas supply system and method for bearing heat treatment, and the carbon potential gas supply system comprises a heating furnace, a propane pipeline, a nitrogen pipeline and a process air pipeline; the propane pipeline, the nitrogen pipeline and the process air pipeline are communicated into a hearth of the heating furnace; the propane pipeline is provided with a propane flowmeter and a propane adjusting flow valve, and the propane pipeline is provided with a propane electromagnetic valve; a nitrogen flow meter is arranged on the nitrogen pipeline, and the nitrogen pipeline behind the nitrogen flow meter is branched to form a plurality of independently controlled nitrogen branches which are communicated into a hearth of the heating furnace; the process air pipeline is connected with an air supply air pump; and an air flow meter, an air adjusting flow valve and an air electromagnetic valve are arranged on the process air pipeline. The gas supply system improves the precision and stability of carbon potential control, and gas supply is automatically adjusted according to the carbon potential in the hearth. A plurality of nitrogen branches are independently controlled, the nitrogen flow change in the heating furnace under different conditions is met, and positive pressure and gas replacement in the furnace are achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of bearing heat treatment, and in particular relates to a carbon potential gas supply system and a gas supply method for bearing heat treatment. Background Art

[0002] During the heat treatment of bearings, precise control of carbon potential is crucial to ensuring bearing quality and performance. Improper carbon potential control can lead to deviations in bearing performance indicators such as hardness, wear resistance, and toughness, affecting the bearing's service life and reliability.

[0003] Existing carbon potential gas supply systems have shortcomings in control accuracy, response speed, and gas mixing uniformity. For example, some systems struggle to quickly and accurately adjust the carbon potential according to real-time heat treatment process requirements, resulting in product quality fluctuations during the heat treatment of different bearing batches. Furthermore, uneven gas mixing can cause localized carbon potential inconsistencies, affecting the overall quality of the bearings. Summary of the Invention

[0004] In view of the defects of the above-mentioned prior art, the purpose of the present invention is to provide a carbon potential air supply system and air supply method for the heat treatment of large wind turbine bearings, which is mainly used for the heat treatment of large wind turbine bearings and can quickly and accurately adjust the carbon potential.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a carbon potential gas supply system for bearing heat treatment, including a heating furnace, a propane pipeline, a nitrogen pipeline and a process air pipeline; the propane pipeline, the nitrogen pipeline and the process air pipeline are connected to the furnace of the heating furnace; the propane pipeline is provided with a propane flowmeter and a propane regulating flow valve for monitoring and regulating the propane flow, and the propane pipeline is also provided with a propane solenoid valve for controlling the propane supply; the nitrogen pipeline is provided with a nitrogen flowmeter, and the nitrogen pipeline behind the nitrogen flowmeter branches to form a plurality of independently controlled nitrogen branches, and the plurality of nitrogen branches are connected to the furnace of the heating furnace, and the nitrogen flow entering the heating furnace is controlled by the plurality of nitrogen branches; the process air pipeline is connected to the air supply air pump, and the process air pipeline is provided with an air flowmeter and an air regulating flow valve for monitoring and regulating the air flow, and the process air pipeline is also provided with an air solenoid valve for controlling the air supply.

[0006] Furthermore, the outlets of the propane pipeline and the process air pipeline are connected to the control main pipe, which is provided with a master control solenoid valve. The control main pipe is connected to the air intake main pipe, which is connected to the heating furnace and communicates with the furnace of the heating furnace; among the multiple nitrogen branches formed by the branches of the nitrogen pipeline, the outlet of the first nitrogen branch is connected to the control main pipe and controlled by the master control solenoid valve, and the outlets of the remaining nitrogen branches are connected to the air intake main pipe.

[0007] Furthermore, the master control solenoid valve is a normally closed solenoid valve, which is turned on after being energized.

[0008] Furthermore, the inlet of the nitrogen pipeline is provided with a nitrogen main valve and a nitrogen pressure reducing valve in sequence; the nitrogen pipeline branches to form the first nitrogen branch, the second nitrogen branch, the third nitrogen branch, and the fourth nitrogen branch; the first nitrogen branch is provided with a first branch manual valve and a first branch regulating valve, the second nitrogen branch is provided with a second branch manual valve and a second branch solenoid valve, the third nitrogen branch is provided with a third branch manual valve, and the fourth nitrogen branch is provided with a fourth branch manual valve and a fourth branch solenoid valve; the outlets of the second nitrogen branch, the third nitrogen branch, and the fourth nitrogen branch are connected to the intake main pipeline.

[0009] Furthermore, the fourth branch solenoid valve is a normally closed solenoid valve, which is turned on after being energized, and the fourth branch solenoid valve is energized for a timed period and loses power when the time ends; the second branch solenoid valve is a normally open solenoid valve, which is closed after being energized, and the third branch manual valve is in a normally closed state.

[0010] Furthermore, the nitrogen pipeline is connected to a cooling nitrogen input pipeline, the inlet of the cooling nitrogen input pipeline is arranged in front of the nitrogen flowmeter, and the outlet of the cooling nitrogen input pipeline is connected to the heating furnace, which is used to cool the roller bearings of the heating furnace channel transmission rollers; the cooling nitrogen input pipeline is provided with a cooling nitrogen control valve and a cooling nitrogen flowmeter.

[0011] Furthermore, the inlet of the propane pipeline is provided with a propane main valve and a propane pressure reducing valve in sequence, a propane manual valve is provided in front of the propane flowmeter, the propane solenoid valve is provided with a bypass, and a bypass valve is connected to the bypass; the propane solenoid valve and the air solenoid valve are normally closed solenoid valves, which are connected after being energized.

[0012] Furthermore, the heating furnace is provided with an oxygen probe, and the reference gas air pump is connected to the oxygen probe connector through the reference gas pipeline and the carbon potential purge gas pipeline. The reference gas pipeline is sequentially provided with a reference gas manual valve and a reference gas flow meter, and the carbon potential purge gas pipeline is sequentially provided with a carbon potential purge gas manual valve, a carbon potential purge gas flow meter and a carbon potential purge gas solenoid valve. The carbon potential purge gas solenoid valve is a normally closed solenoid valve, which is turned on after being energized. The carbon potential purge gas solenoid valve is turned on for 60-90 seconds every 3-8 hours.

[0013] Furthermore, the heating furnace is connected to an ammonia pipeline, which is connected to the furnace of the heating furnace and is used for carbonitriding and is controlled by a manual valve. An ammonia flowmeter is provided on the ammonia pipeline.

[0014] Furthermore, the propane pipeline, nitrogen pipeline and process air pipeline are respectively provided with pointer pressure gauges.

[0015] The gas supply method of the carbon potential gas supply system for the above-mentioned bearing heat treatment is that the gas supply button of the heating furnace controls the master control solenoid valve, and the master control solenoid valve is a normally closed solenoid valve. When the gas supply button is turned on, the master control solenoid valve is energized and turned on, and when the gas supply button is closed, the master control solenoid valve is de-energized and closed; the stability of the carbon potential is controlled by the propane solenoid valve and the air solenoid valve. When the actual carbon potential in the furnace is lower than the set value, the propane solenoid valve is energized and turned on, and the air solenoid valve is de-energized and closed; when the actual carbon potential in the furnace is higher than the set value, the propane solenoid valve is de-energized and closed, and the air solenoid valve is energized and turned on. The output time and frequency of the air solenoid valve 13 and the propane solenoid valve 9 are adjusted by the instrument through PID; the nitrogen pipeline is used to maintain Positive pressure is maintained in the heating furnace and gas replacement is performed in the furnace; when the gas supply button is disconnected or the equipment is powered off, the second branch solenoid valve loses power and is connected. At this time, the main control solenoid valve and the fourth branch solenoid valve lose power and are closed, and nitrogen is introduced into the furnace through the second nitrogen branch to ensure positive pressure in the furnace; when the gas supply button is connected, the second branch solenoid valve is powered on and closed, the main control solenoid valve is powered on and is connected, and nitrogen is introduced into the furnace through the first nitrogen branch; after the furnace door of the heating furnace is opened and closed, the fourth branch solenoid valve is powered on for a timed period, and loses power and is closed after the time is up. The fourth nitrogen branch introduces nitrogen into the furnace during the time that the fourth branch solenoid valve is powered on; the third nitrogen branch is used as an emergency passage when the solenoid valve fails.

[0016] Furthermore, when the furnace temperature of the heating furnace is greater than or equal to 790°, the gas supply button is automatically or manually turned on, the reference gas air pump starts running, the reference gas pipeline and the carbon potential purge gas pipeline supply air to the oxygen probe joint, and the reference gas pipeline supplies the air output by the reference gas air pump at a flow rate of 25L / H to the oxygen probe reference gas port, and the carbon potential purge gas solenoid valve is energized and turned on at a timed rate, and is turned on for 60-90 seconds every 3-8 hours, and is adjusted according to the carbon black situation in the furnace.

[0017] Furthermore, when the heating furnace is waiting for material, the temperature is set at 820°C, and the carbon potential is set at 0.85%CP. When the actual carbon potential in the furnace is lower than 0.85%CP, the propane solenoid valve is energized and turned on, and the air solenoid valve is de-energized and closed; when the actual carbon potential in the furnace is higher than 0.85%CP, the propane solenoid valve is de-energized and closed, and the air solenoid valve is energized and turned on; the instrument adjusts the output time and frequency of the air solenoid valve and the propane solenoid valve through PID.

[0018] Based on the above technical solution, it should be noted that the air solenoid valve 13 and the propane solenoid valve 9 are not complementary conditions. If the carbon potential is set to 0.85% CP, the solenoid valve is controlled by adjusting the PID parameters. When the actual value is much smaller than the set value, the propane solenoid valve is always energized. When the actual value is close to 0.85% CP, the frequency is adjusted to energize. When the actual value is close to 0.85% CP, the propane solenoid valve is energized at an extremely low frequency. When the actual value is higher than 0.85, the air solenoid valve will have a PID output based on the judgment. When the actual value is much higher than 0.85, the frequency of the air solenoid valve energization increases or it is always energized.

[0019] Furthermore, when the gas supply is disconnected or the equipment is out of power or abnormal, the second branch solenoid valve loses power and is connected. At this time, the main control solenoid valve and the fourth branch solenoid valve lose power and are closed, and the second nitrogen branch introduces 15m³ / H of nitrogen into the furnace to ensure positive pressure in the furnace; when the gas supply button is turned on, the second branch solenoid valve is energized and closed, the main control solenoid valve is energized and connected, and the first nitrogen branch introduces 7.5m³ / H of nitrogen into the furnace; when a new workpiece enters the heating furnace and the furnace door is closed, the first nitrogen branch continues to introduce 7.5m³ / H of nitrogen into the furnace, and the fourth branch solenoid valve is energized for 35 minutes. The fourth nitrogen branch introduces 3.5m³ / H of nitrogen into the furnace. At this time, the nitrogen flow rate in the furnace is 11m³ / H. After 35 minutes, the fourth branch solenoid valve loses power and is closed, and the fourth nitrogen branch is closed.

[0020] The beneficial effects of the present invention include: The carbon potential gas supply system for bearing heat treatment improves the precision and stability of carbon potential control, ensuring consistent bearing heat treatment quality. The propane and process air lines automatically adjust according to the carbon potential within the furnace, using PID control of output time and frequency for rapid response. Multiple nitrogen branches are independently controlled to accommodate varying nitrogen flow rates within the heating furnace under varying conditions, achieving positive pressure and gas displacement within the furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the carbon potential gas supply system for bearing heat treatment of the present invention; Figure: 1. Reference air pump, 2. Reference air flow meter, 3. Carbon potential purge gas flow meter, 4. Carbon potential purge gas solenoid valve, 5. Ammonia flow meter, 6. Propane manual valve, 7. Propane flow meter, 8. Propane regulating flow valve, 9. Propane solenoid valve, 10. Supply air pump, 11. Air flow meter, 12. Air regulating flow valve, 13. Air solenoid valve, 14. Nitrogen main valve, 15. Nitrogen flow meter, 16. Cooling nitrogen flow meter, 17. First branch manual valve, 18. Second branch manual valve, 19. Third branch manual valve, 20. First branch regulating valve, 21. Second branch solenoid valve, 22. Fourth branch solenoid valve, 23. Master control solenoid valve, 24. Oxygen probe, 25. Cooling nitrogen control valve, 26. Propane main valve, 27. Propane pressure reducing valve. 28. Bypass valve, 29. Nitrogen pressure reducing valve, 30. Propane pointer pressure gauge, 31. Fourth branch manual valve, 32. Heating furnace, 33. Air pointer pressure gauge, 34. Nitrogen pointer pressure gauge, 35. Reference air manual valve, 36. Carbon potential purge air manual valve; 100, propane pipeline, 200, process air pipeline, 300, nitrogen pipeline, 301, first nitrogen branch, 302, second nitrogen branch, 303, third nitrogen branch, 304, fourth nitrogen branch, 3000, nitrogen input pipeline for cooling, 400, main air intake pipeline, 500, reference gas pipeline, 600, carbon potential purge gas pipeline, 700, ammonia pipeline, 800, control main pipeline. DETAILED DESCRIPTION

[0022] In order to make the structure and function of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0023] See attached Figure 1 The carbon potential gas supply system for bearing heat treatment includes a heating furnace 32, a propane pipeline 100, a nitrogen pipeline 300 and a process air pipeline 200; the propane pipeline 100, the nitrogen pipeline 300 and the process air pipeline 200 are connected to the furnace of the heating furnace 32.

[0024] The inlet of the propane pipeline 100 is provided with a propane main valve 26, a propane pressure reducing valve 27 and a propane manual valve 6 in sequence. The rear path of the propane manual valve 6 is provided with a propane pointer pressure gauge 30, a propane flow meter 7, a propane regulating flow valve 8 and a propane solenoid valve 9 in sequence. The propane pointer pressure gauge 30 is used to display the pressure in the propane pipeline 100, the propane flow meter 7 is used to detect and display the propane flow, the propane regulating flow valve 8 is used to regulate the propane flow, and the propane solenoid valve 9 is used to control the propane supply. The propane solenoid valve 9 is provided with a bypass, and a bypass valve 28 is connected to the bypass. The bypass valve 28 is used to bypass the propane solenoid valve 9 in special circumstances; the propane solenoid valve 9 is a normally closed solenoid valve and is opened after being energized.

[0025] The process air pipeline 200 is connected to the air supply air pump 10, and the process air pipeline 200 is provided with an air pointer pressure gauge 33, an air flow meter 11, an air regulating flow valve 12 and an air solenoid valve 13 in sequence. The air pointer pressure gauge 33 is used to display the pressure in the process air pipeline 200, the air regulating flow valve 12 is used to detect and display the air flow, the air regulating flow valve 12 is used to adjust the air flow, and the air solenoid valve 13 is used to control the air supply. The air solenoid valve 13 is a normally closed solenoid valve and is turned on when powered.

[0026] The inlet of the nitrogen pipeline 300 is provided with a nitrogen main valve 14 and a nitrogen pressure reducing valve 29 in sequence; the nitrogen pipeline 300 is provided with a nitrogen pointer pressure gauge 34 and a nitrogen flowmeter 15. The nitrogen pipeline after the nitrogen flowmeter 15 branches to form four independently controlled nitrogen branches, and the four nitrogen branches are connected to the furnace of the heating furnace 32 to control the nitrogen flow entering the heating furnace.

[0027] Furthermore, the outlets of the propane pipeline 100 and the process air pipeline 200 are connected to a control manifold 800, which is provided with a master control solenoid valve 23. The control manifold 800 is connected to the air intake manifold 400, which is in turn connected to the heating furnace 32 and communicates with the furnace chamber of the heating furnace. Of the four nitrogen branches formed by the nitrogen pipeline, the outlet of the first nitrogen branch 301 is connected to the control manifold 800 and controlled by the master control solenoid valve 23, while the outlets of the remaining nitrogen branches are connected to the air intake manifold 400. The master control solenoid valve 23 is a normally closed solenoid valve that opens when energized.

[0028] Specifically, the nitrogen pipeline 300 branches into a first nitrogen branch 301, a second nitrogen branch 302, a third nitrogen branch 303 and a fourth nitrogen branch 304. The first nitrogen branch 301 is provided with a first branch manual valve 17 and a first branch regulating valve 20. The outlet of the first nitrogen branch 301 is connected to the control main pipe 800 and is controlled by the main control solenoid valve 23; the second nitrogen branch 302 is provided with a second branch manual valve 18 and a second branch solenoid valve 21, the third nitrogen branch 303 is provided with a third branch manual valve 19, and the fourth nitrogen branch 304 is provided with a fourth branch manual valve 31 and a fourth branch solenoid valve 22; the outlets of the second nitrogen branch 302, the third nitrogen branch 303 and the fourth nitrogen branch 304 are connected to the intake main pipeline.

[0029] The fourth branch solenoid valve 22 is a normally closed solenoid valve, which is conductive when energized, and the fourth branch solenoid valve 22 is energized for a timed period and de-energized when the time expires. The fourth nitrogen branch 304 is used for when the carbon potential in the furnace is reduced after the furnace door is opened and closed. Air will enter the furnace after the furnace door is opened and closed, and the oxygen in the air will absorb carbon atoms, reducing the carbon potential. Therefore, nitrogen must be quickly replenished to quickly discharge the air from the furnace for replacement; the second branch solenoid valve 21 is a normally open solenoid valve, which is closed when energized. The second branch solenoid valve 21 is controlled by the gas supply button of the heating furnace. When the gas supply button is turned on, the second branch solenoid valve 21 is energized and closed. When the gas supply button is closed, the second branch solenoid valve 21 is de-energized and conductive. The second nitrogen branch 302 is used to introduce nitrogen into the heating furnace when the equipment is in an abnormal state to protect the positive pressure in the furnace and eliminate safety hazards; the third branch manual valve 19 is in a normally closed state, and the third nitrogen branch 303 is used as an emergency channel when the solenoid valve fails.

[0030] Furthermore, the nitrogen pipeline 300 is connected to the cooling nitrogen input pipeline 3000, the inlet of the cooling nitrogen input pipeline 3000 is set between the nitrogen pointer pressure gauge 34 and the nitrogen pressure reducing valve 29, and the outlet of the cooling nitrogen input pipeline 3000 is connected to the heating furnace 32, which is used to cool the roller bearings of the heating furnace channel transmission rollers; the cooling nitrogen input pipeline 3000 is provided with a cooling nitrogen control valve 25 and a cooling nitrogen flowmeter 16.

[0031] Furthermore, the heating furnace 32 is provided with an oxygen probe 24, and the reference gas air pump 1 is connected to the oxygen probe 24 connector through the reference gas pipeline 500 and the carbon potential purge gas pipeline 600. The reference gas pipeline 500 is sequentially provided with a reference gas manual valve 35 and a reference gas flow meter 2, and the carbon potential purge gas pipeline 600 is sequentially provided with a carbon potential purge gas manual valve 36, a carbon potential purge gas flow meter 3 and a carbon potential purge gas solenoid valve 4. The carbon potential purge gas solenoid valve 4 is a normally closed solenoid valve and is energized at a fixed time. It is turned on after being energized. The time of the carbon potential purge gas solenoid valve 4 can be set by the operation screen, and it is connected for 60-90 seconds every 3-8 hours. The specific setting depends on the carbon black situation in the furnace.

[0032] Furthermore, the heating furnace 32 is connected to an ammonia pipeline 700 , which is communicated with the furnace of the heating furnace 32 and is used for carbonitriding and is manually controlled by adjusting a manual valve. An ammonia flowmeter 5 is provided on the ammonia pipeline 700 .

[0033] Gas supply method of the carbon potential gas supply system for the above bearing heat treatment: The carbon potential purge gas solenoid valve 4, propane solenoid valve 9, air solenoid valve 13, fourth branch solenoid valve 22 and master control solenoid valve 23 are normally closed solenoid valves, which are turned on when energized; the second branch solenoid valve 21 is a normally open solenoid valve, which is closed when energized.

[0034] This embodiment takes the heat treatment process of a large wind turbine bearing as an example: When the furnace temperature of the heating furnace 32 is greater than or equal to 790°, the gas supply button is automatically or manually turned on; after the gas supply button is turned on, the button display is bright, indicating normal gas supply, the reference gas air pump 1 is running, the reference gas pipeline 500 and the carbon potential purge gas pipeline 600 supply air to the oxygen probe 24 joint, and the reference gas pipeline 500 supplies the air output by the reference gas air pump 1 at a flow rate of 25L / H to the oxygen probe reference gas port. The carbon potential purge gas solenoid valve 4 is energized and turned on at a timed rate, and is connected for 60-90 seconds every 3-8 hours. The time is set by the operation screen and adjusted according to the carbon black situation in the furnace.

[0035] The gas supply button of the heating furnace 32 controls the main control solenoid valve 23, which is a normally closed solenoid valve. When the gas supply button is turned on, the main control solenoid valve 23 is energized and turned on. When the gas supply button is closed, the main control solenoid valve 23 is de-energized and turned off. When the heating furnace is waiting for material, the temperature is set to 820°C, and the carbon potential is set to 0.85%CP. The stability of the carbon potential is controlled by the propane solenoid valve 9 and the air solenoid valve 13. When the actual carbon potential in the furnace is lower than 0.85%CP, the propane solenoid valve 9 is energized and turned on, the air solenoid valve 13 is de-energized and closed, and propane is introduced into the furnace. When the actual carbon potential in the furnace is higher than 0.85%CP, the propane solenoid valve 9 is de-energized and closed, the air solenoid valve 13 is energized and turned on, and air is introduced into the furnace. The output time and frequency of the air solenoid valve 13 and the propane solenoid valve 9 are adjusted by the instrument through PID.

[0036] Based on the above technical solution, it should be noted that the air solenoid valve 13 and the propane solenoid valve 9 are not complementary conditions. If the carbon potential is set to 0.85% CP, the solenoid valve is controlled by adjusting the PID parameters. When the actual value is much smaller than the set value, the propane solenoid valve is always energized. When the actual value is close to 0.85% CP, the frequency is adjusted to energize. When the actual value is close to 0.85% CP, the propane solenoid valve is energized at an extremely low frequency. When the actual value is higher than 0.85, the air solenoid valve will have a PID output based on the judgment. When the actual value is much higher than 0.85, the frequency of the air solenoid valve energization increases or it is always energized.

[0037] The nitrogen pipeline is used to maintain positive pressure in the heating furnace and to replace the gas in the furnace; Under normal gas supply conditions, the gas supply button is turned on, the second branch solenoid valve 21 is powered on and closed, the master control solenoid valve 23 is powered on and conducted, and the fourth branch solenoid valve 22 is not powered on and closed, the first nitrogen branch 301 introduces 7.5 m³ / H of nitrogen into the furnace, and the total nitrogen flow rate in the furnace is 7.5 m³ / H; When a new workpiece enters the heating furnace, the carbon potential immediately drops to a very low level after the furnace door is opened. After the new workpiece enters the furnace and the furnace door is fully closed, the first nitrogen branch 301 introduces 7.5 m³ / H of nitrogen into the furnace at its original flow rate. The fourth branch solenoid valve 22 is energized for 35 minutes, and the fourth nitrogen branch 304 introduces 3.5 m³ / H of nitrogen into the furnace. The total nitrogen flow rate in the furnace is now 7.5 + 3.5 = 11 m³ / H. After 35 minutes, the fourth branch solenoid valve 22 loses power and closes, closing the fourth nitrogen branch 304 and restoring the total nitrogen flow rate to 7.5 m³ / H. This large nitrogen supply is intended to counteract the ingress of air into the furnace after the door is opened. This allows the carbon potential in the furnace to quickly rise to the set value, allowing the fastest displacement reaction and rapid carbon potential buildup. This ensures complete decarburization of the product. Propane and process air are automatically adjusted based on the carbon potential.

[0038] A main power outage closes all solenoid valves. The absence of a gas source in the furnace creates negative pressure, posing an explosion risk. Therefore, the gas supply button controls the second branch solenoid valve 21. When the gas supply button is turned on, the second branch solenoid valve 21 is powered on and closed. When the gas supply button is turned off, the second branch solenoid valve 21 loses power and remains open. If the gas supply is disconnected or an abnormal condition occurs in the equipment, such as low furnace pressure or a main power outage, the second branch solenoid valve 21 loses power and remains open. At this point, the master control solenoid valve 23 and the fourth branch solenoid valve 22 lose power and close. The second nitrogen branch 302 introduces 15 m³ / H of nitrogen into the furnace, ensuring a total flow rate of 15 m³ / H. This maintains positive pressure within the furnace and eliminates safety hazards.

[0039] When all electromagnetic valves fail, the third branch manual valve 19 is opened manually, and nitrogen is introduced into the furnace through the third nitrogen branch 303 to ensure positive pressure in the furnace.

[0040] It should be noted that the parts not described in detail in the present invention are prior art.

[0041] The above examples are merely preferred embodiments of the present invention. Obviously, the present invention is not limited to the above examples, and many variations are possible. All variations that can be directly derived or imagined by a person skilled in the art from the disclosure of the present invention should be considered to be within the scope of protection of the present invention.

Claims

1. Carbon potential gas supply system for bearing heat treatment, characterized by: It includes a heating furnace, a propane pipeline, a nitrogen pipeline and a process air pipeline; the propane pipeline, the nitrogen pipeline and the process air pipeline are connected to the furnace of the heating furnace; the propane pipeline is provided with a propane flowmeter and a propane regulating flow valve for monitoring and regulating the propane flow, and the propane pipeline is also provided with a propane solenoid valve for controlling the propane supply; the nitrogen pipeline is provided with a nitrogen flowmeter, and the nitrogen pipeline after the nitrogen flowmeter branches to form multiple independently controlled nitrogen branches, and the multiple nitrogen branches are connected to the furnace of the heating furnace; the process air pipeline is connected to the air supply air pump, and the process air pipeline is provided with an air flowmeter and an air regulating flow valve for monitoring and regulating the air flow, and the process air pipeline is also provided with an air solenoid valve for controlling the air supply.

2. The carbon potential gas supply system for bearing heat treatment according to claim 1, characterized in that: The outlets of the propane pipeline and the process air pipeline are connected to the control main pipe, which is provided with a master control solenoid valve. The control main pipe is connected to the air intake main pipe, which is connected to the heating furnace and communicates with the furnace of the heating furnace; among the multiple nitrogen branches formed by the nitrogen pipeline branches, the outlet of the first nitrogen branch is connected to the control main pipe and controlled by the master control solenoid valve, and the outlets of the remaining nitrogen branches are connected to the air intake main pipe.

3. The carbon potential gas supply system for bearing heat treatment according to claim 2, characterized in that: The inlet of the nitrogen pipeline is provided with a nitrogen main valve and a nitrogen pressure reducing valve in sequence; the nitrogen pipeline branches to form the first nitrogen branch, the second nitrogen branch, the third nitrogen branch, and the fourth nitrogen branch; the first nitrogen branch is provided with a first branch manual valve and a first branch regulating valve, the second nitrogen branch is provided with a second branch manual valve and a second branch solenoid valve, the third nitrogen branch is provided with a third branch manual valve, and the fourth nitrogen branch is provided with a fourth branch manual valve and a fourth branch solenoid valve; the outlets of the second nitrogen branch, the third nitrogen branch, and the fourth nitrogen branch are connected to the intake main pipeline; the main control solenoid valve and the fourth branch solenoid valve are normally closed solenoid valves, which are turned on when energized, and the fourth branch solenoid valve is energized for a timed period and loses power when the time ends; the second branch solenoid valve is a normally open solenoid valve, which is closed when energized, and the third branch manual valve is in a normally closed state.

4. The carbon potential gas supply system for bearing heat treatment according to claim 1, characterized in that: The nitrogen pipeline is connected to the cooling nitrogen input pipeline, the inlet of the cooling nitrogen input pipeline is arranged in front of the nitrogen flowmeter, and the outlet of the cooling nitrogen input pipeline is connected to the heating furnace, which is used to cool the roller bearings of the heating furnace channel transmission rollers; the cooling nitrogen input pipeline is provided with a cooling nitrogen control valve and a cooling nitrogen flowmeter.

5. The carbon potential gas supply system for bearing heat treatment according to claim 1, characterized in that: The inlet of the propane pipeline is provided with a propane main valve and a propane pressure reducing valve in sequence, a propane hand valve is provided in front of the propane flowmeter, the propane solenoid valve is provided with a bypass, and a bypass valve is connected to the bypass; the propane solenoid valve and the air solenoid valve are normally closed solenoid valves, and are connected after being energized.

6. The carbon potential gas supply system for bearing heat treatment according to claim 1, characterized in that: The heating furnace is provided with an oxygen probe, and the reference gas air pump is connected to the oxygen probe joint through the reference gas pipeline and the carbon potential purge gas pipeline. The reference gas pipeline is sequentially provided with a reference gas manual valve and a reference gas flow meter, and the carbon potential purge gas pipeline is sequentially provided with a carbon potential purge gas manual valve, a carbon potential purge gas flow meter and a carbon potential purge gas solenoid valve. The carbon potential purge gas solenoid valve is a normally closed solenoid valve, which is turned on after being energized. The carbon potential purge gas solenoid valve is turned on for 60-90 seconds every 3-8 hours.

7. The carbon potential gas supply system for bearing heat treatment according to claim 1, characterized in that: The heating furnace is connected to an ammonia pipeline, which is connected to the furnace of the heating furnace and is used for carbonitriding and is controlled by a manual valve. An ammonia flowmeter is provided on the ammonia pipeline; pointer pressure gauges are respectively provided on the propane pipeline, nitrogen pipeline and process air pipeline.

8. A gas supply method using a carbon potential gas supply system for bearing heat treatment according to any one of claims 1 to 7, characterized in that: The gas supply button of the heating furnace controls the master control solenoid valve, which is a normally closed solenoid valve. When the gas supply button is turned on, the master control solenoid valve is energized and turned on. When the gas supply button is closed, the master control solenoid valve is de-energized and closed. The stability of the carbon potential is controlled by the propane solenoid valve and the air solenoid valve. When the actual carbon potential in the furnace is lower than the set value, the propane solenoid valve is energized and turned on, and the air solenoid valve is de-energized and closed. When the actual carbon potential in the furnace is higher than the set value, the propane solenoid valve is de-energized and closed, and the air solenoid valve is energized and turned on. The output time and frequency of the air solenoid valve and the propane solenoid valve are adjusted by the instrument through PID. The nitrogen pipeline is used to maintain The heating furnace is under positive pressure and the gas in the furnace is replaced; when the gas supply button is disconnected or the equipment is powered off, the second branch solenoid valve loses power and is turned on. At this time, the main control solenoid valve and the fourth branch solenoid valve lose power and are closed, and the second nitrogen branch introduces nitrogen into the furnace to ensure positive pressure in the furnace; when the gas supply button is turned on, the second branch solenoid valve is powered on and closed, the main control solenoid valve is powered on and turned on, and the first nitrogen branch introduces nitrogen into the furnace; after the furnace door of the heating furnace is opened and closed, the fourth branch solenoid valve is energized for timing, and loses power and is closed at the end of the time. The fourth nitrogen branch introduces nitrogen into the furnace during the time when the fourth branch solenoid valve is energized and turned on.

9. The gas supply method of the carbon potential gas supply system for bearing heat treatment according to claim 8, characterized in that: When the furnace temperature of the heating furnace is greater than or equal to 790°, the gas supply button is automatically or manually turned on, the reference gas air pump starts running, the reference gas pipeline and the carbon potential purge gas pipeline supply air to the oxygen probe joint, and the reference gas pipeline supplies the air output by the reference gas air pump at a flow rate of 25L / H to the oxygen probe reference gas port. The carbon potential purge gas solenoid valve is energized and turned on at a timed rate, and is turned on for 60-90 seconds every 3-8 hours, and is adjusted according to the carbon black situation in the furnace.

10. The gas supply method of the carbon potential gas supply system for bearing heat treatment according to claim 8, characterized in that: When the heating furnace is waiting for material, the temperature is set at 820°C and the carbon potential is set at 0.85%CP. When the actual carbon potential in the furnace is lower than 0.85%CP, the propane solenoid valve is energized and turned on, and the air solenoid valve is de-energized and closed; when the actual carbon potential in the furnace is higher than 0.85%CP, the propane solenoid valve is de-energized and closed, and the air solenoid valve is energized and turned on. The instrument adjusts the output time and frequency of the air solenoid valve and the propane solenoid valve through PID; when the gas supply is disconnected or the equipment is powered off or abnormal, the second branch solenoid valve is de-energized and turned on, at this time the main control solenoid valve and the fourth branch solenoid valve are de-energized and closed, The second nitrogen branch introduces 15m³ / H of nitrogen into the furnace to ensure positive pressure in the furnace; the gas supply button is turned on, the second branch solenoid valve is energized and closed, the main control solenoid valve is energized and turned on, and the first nitrogen branch introduces 7.5m³ / H of nitrogen into the furnace; after the new workpiece enters the heating furnace and the furnace door is closed, the first nitrogen branch continues to introduce 7.5m³ / H of nitrogen into the furnace, the fourth branch solenoid valve is energized for 35 minutes, and the fourth nitrogen branch introduces 3.5m³ / H of nitrogen into the furnace. At this time, the nitrogen flow rate in the furnace is 11m³ / H. After 35 minutes, the fourth branch solenoid valve loses power and closes, and the fourth nitrogen branch is closed.

Images