Vacuum sintering furnace is a furnace that uses induction heating for protective sintering of heated items. It can be divided into power frequency, medium frequency, high frequency and other types, and can be classified as a subcategory of vacuum sintering furnace. The vacuum induction sintering furnace is a complete set of equipment that uses the principle of medium-frequency induction heating to sinter cemented carbide cutter heads and various metal powder compacts under vacuum or protective atmosphere conditions. It is used for cemented carbide, dysprosium metal, and ceramic materials. Designed for industrial production.
So, how do we operate a vacuum sintering furnace safely?
1. The cooling water source of the intermediate frequency power supply, vacuum furnace body, and induction coil - the water reservoir must be full, and there must be no impurities in the water. vacuum furnace
2. Start the water pump to ensure that the medium frequency power supply, vacuum furnace induction coil, and furnace cooling system water circulation are normal, and adjust the water pressure to the specified value.
3. Check the vacuum pump power system, the belt pulley belt is tight, and whether the vacuum pump oil is located in the center line of the oil seal observation hole. After the inspection is complete, manually rotate the vacuum pump belt pulley. If there is no abnormality, the vacuum pump can be started with the butterfly valve closed.
4. Check the condition of the vacuum furnace body. It is required that the vacuum furnace body is first-level hygienic, the induction coil is well insulated, the sealing vacuum tape is elastic, and the size is qualified.
5. Check whether the lever handle of the vacuum furnace body is flexible to start.
6. Check whether the rotary Maxwell vacuum gauge meets the requirements.
7. Check whether the graphite crucible and furnace accessories are complete.
8. After the above preparations are completed, turn on the power supply, close the intermediate frequency power supply, and try to start the frequency conversion according to the intermediate frequency starting rules. After success, stop the frequency conversion before starting the furnace.
9. The observation and temperature measurement holes on the upper cover of the vacuum furnace body need to be cleaned every time the furnace is opened to facilitate observation and temperature measurement.
10. When loading the furnace, corresponding furnace loading methods should be adopted according to different sintered products. Pack the plates according to the relevant material loading rules and do not change them at will.
11. In order to maintain a constant temperature and prevent heat radiation, add two layers of carbon fiber to the heating crucible and then cover it with a heat shield.
12. Cover with vacuum sealing tape.
13. Operate the lever handle, turn the top cover of the vacuum furnace to closely overlap with the furnace body, lower the top cover, and lock the fixing nut.
14. Slowly open the butterfly valve and extract air from the furnace body until the vacuum reaches the specified value.
15. After the vacuum degree reaches the specified requirements, start the frequency conversion, adjust the intermediate frequency power, and operate according to the sintering regulations of the relevant materials; heat up, heat preservation and cooling.
16. After sintering is completed, stop the frequency conversion, press the stop frequency conversion switch, the inverter will stop working, disconnect the intermediate frequency power supply branch gate and disconnect the main power supply gate.
17. After observing that the furnace is black through the observation hole of the furnace body, first close the vacuum pump butterfly valve and disconnect the vacuum pump current, then connect tap water to continue cooling the induction coil and furnace body, and finally stop the water pump.
18. The medium frequency voltage of 750 volts may cause electric shock. During the entire operation and inspection process, pay attention to operational safety and do not touch the intermediate frequency cabinet with your hands.
19. During the sintering process, observe whether arcing occurs in the induction coil through the observation hole on the side of the furnace at any time. If any abnormality is found, report it to the relevant personnel immediately for handling.
20. The vacuum butterfly valve should be started slowly, otherwise oil will leak out due to excessive air pumping, which will bring adverse consequences.
21. Use the rotary Maxwell vacuum gauge correctly, otherwise it will cause vacuum reading errors or cause mercury to overflow due to excessive operation and cause public nuisance.
22. Pay attention to the safe operation of the vacuum pump belt pulley.
23. When applying vacuum sealing tape and covering the top cover of the furnace body, be careful not to pinch your hands.
24. Under vacuum conditions, any workpiece or container that is easily volatilized and affects vacuum hygiene, causing pipeline blockage and vacuum pump dirtying, must not be put into the furnace.
25. If the product contains a molding agent (such as oil or paraffin), it must be removed before being sintered in the furnace, otherwise it will cause adverse consequences.
26. During the entire sintering process, attention should be paid to the pressure range of the water meter and cooling water circulation to avoid accidents.
Post time: Nov-24-2023