Handling of these two issues in the trolley annealing furnace

1, Temperature control during annealing process:
The trolley annealing furnace adopts dual closed-loop control of combustion chamber temperature and material chamber temperature, with the temperature set value of combustion chamber temperature closed-loop control being 850 ℃ higher than the heating hood. The two closed-loop systems switch between each other based on the current heating situation of the heating hood and the temperature of the material chamber. The specific switching conditions are:
(1) If the temperature in the chamber is greater than or equal to its set value, it is necessary to switch from the combustion chamber closed-loop to the chamber closed-loop.
(2) If the actual temperature of the combustion chamber rises by 10 ℃ or exceeds the set value of the heating hood or the actual temperature of the material chamber drops by 15 ℃, it needs to be switched back to closed-loop control of the combustion chamber.
The control methods are further divided into adjustment control and switch control, and the specific conversion conditions are:
(1) If the following situations occur in the trolley annealing furnace, it is necessary to switch from regulating control to on/off control: the temperature of the combustion chamber is 10 ℃ or higher than the set value, and the lower the set value has been reached on the electric valve; Or the temperature in the material room may be 4 ℃ or higher than the set value, and the electric valve has reached a smaller set value; Or the temperature in the material room may be 7 ℃ or higher than the set value.
(2) If the following situations occur, switch from switch control to adjustment control: the temperature of the combustion chamber drops below the set value by 15 ℃ or even lower; Or the temperature in the material room may drop below the set value by 6 ℃ or even lower. In temperature regulation control, a P regulator is used, which is achieved through cascade control. The temperature closed-loop control is the main loop, the actuator is the air flow control, the gas flow control is the secondary loop, and the actuator is the gas flow control valve.
2, Measures for low vacuum efficiency in annealing furnaces:
At present, based on production practice, there are various factors that contribute to the low vacuum pumping efficiency of the trolley annealing furnace. By analyzing the factors that cause the low efficiency of vacuum pumping in the annealing furnace, combined with production practice and maintenance labor results, increasing repair cycles, and effectively increasing equipment operation efficiency and productivity, the following effective mechanisms and measures are adopted:
1. Vibration reduction treatment for trolley type annealing furnace:
In order to reduce or remove sealing problems, equipment should be inspected irregularly, and specific treatments should be given to rotary vane pumps and booster pumps. Steel plates or gaskets should be added according to the actual situation. Adding gaskets can greatly improve the defect of bolt loosening and weakened sealing caused by vibration during the operation of the unit. Strengthening the support of steel plates can increase the anti vibration performance of the equipment.
2. Strengthen the management of oil products in annealing furnaces:
We should strictly control the oil used in the trolley annealing furnace, strive to achieve comprehensive monitoring, and timely obtain control feedback. The source of goods is an important link in the initial stage of oil products, and it should be observed thoroughly to directly purchase from the source of oil products as much as possible, in order to avoid counterfeit and shoddy products and ensure stable quality of the source of goods. Based on the proposal of the source of oil products, efforts should be made to gradually unify the oil products.