Related techniques for temperature control of dewaxing kettle according to the process curve

In order to achieve the goal of strictly following the process curve for temperature control in vacuum dewaxing reactors, many aspects cannot be ignored.
The structure of the heater should be reasonable, and the configuration of the electric heating elements should ensure the uniformity of the furnace temperature. Try to pack the materials in the tray as much as possible, which is beneficial for uniform temperature. The position of the thermocouple should be able to accurately and timely reflect temperature changes, and its performance should be stable. At present, although B-type thermocouples are more expensive, they still demonstrate their applicability in the dewaxing and sintering process due to their high accuracy and suitable temperature measurement range.
The current power supply for vacuum dewaxing reactors mainly uses controllable silicon voltage regulators and magnetic voltage regulators. The controllable silicon voltage regulator has good regulation performance and high efficiency. When selecting, it is necessary to add a voltage reducing transformer and note that the thyristor power supply should adapt to the inductive load of the transformer. Magnetic voltage regulator is a controllable transformer with control winding and working winding. It is actually a combination of a saturated reactor and a transformer, with good external characteristics. Due to the presence of the reactor, the load waveform is distorted. However, as the output power increases, the load waveform is significantly improved, and the power factor is also greatly increased. When using a magnetic voltage regulator, it is advisable to choose one with a lower starting voltage, as slow heating in the low-temperature zone is crucial for dewaxing sintering.
It is advisable to use the SERVES algorithm in this furnace, which can fully play the role of sub adjustment, overcome system inertia, ensure timely power adjustment during the heating process, and make the actual heating curve match the set curve well.
The self-tuning of the parameters of the dewaxing kettle is based on the response of the closed-loop system from disturbance dynamic to stable state, and calculates the optimal PID tuning value on its own. However, the tuning process may cause excessive calibration, which is not allowed for certain components.
We can reduce the relevant temperature values appropriately when setting the program. In addition, existing instruments can reduce overshoot in some aspects through amplitude limiting measures. When self-tuning parameters, it should be noted that the low-temperature zone requires a longer time due to slow cooling and excessive adjustment. Sufficient time should be left when setting the program, otherwise the tuning process may not be completed and the time has passed, and the parameters will not be able to be tuned. The operator should master some basic knowledge of automatic control as much as possible, understand the impact of different adjustment parameters on control performance, and not necessarily perform self-tuning on every program curve, as running from low to high temperature requires a lot of time and energy consumption, as well as a large amount of electricity and cooling water. As long as you have a clear understanding of this system, it is possible to directly select the appropriate adjustment parameters.