Heating control method for electric carburizing furnace

Abstract

The invention relates the carbonizing electric stove heating controlling mean. The method adopts the zero-cross triggering gate circuit transistor technology and carbonizing electric stove heating controlling mean, and the relay switch signal is replaced by the gate circuit transistor impulse signal. The gate circuit transistor receives the 0-10V or 4-20mA signal from temperature controller, then the output and input signal from zero-cross impulsion triggers gate circuit transistor to change the gate circuit transistor conducting and cut-off time to control the furnace temperature. The invention has the advantages of good economy, simple structure and easy maintenance. The invention suits to the carburizing furnace heating controlling field.

Description

technical field [0001] The invention belongs to the technical field of carburizing electric furnace heating control. Background technique [0002] The large-scale heat treatment equipment used for carburizing the surface of railway bearings --- carburizing electric furnace, its heating actuator adopts thyristor converter technology, which is composed of thyristor AC switch, connected with AC power supply and load. When working, the temperature regulator receives and amplifies the input temperature difference signal of the electric furnace, and sends a relay switch voltage signal to the gate of the thyristor to directly trigger the conduction of the thyristor to supply power to the electric furnace for heating. This electric furnace heating control method actually uses the leakage current of the thyristor cathode to trigger the conduction of the thyristor, which belongs to the strong trigger control method. [0003] Although this temperature control method is simple in struc...

AI Technical Summary

Problems solved by technology

This not only wastes a lot of electric energy, but also the frequent input of high voltage and high current for a long time forms a thermal shock on the electric furnace heater - the electric radiant tube, which increases the heat load and reduces its service life

Every year, more than 20 electric radiant tubes are burned due to thermal shock. Due to its high price, it will cost more than 400,000 yuan to replace it once, and the maintenance time is long, which affects the quality and output of the processed products

[0004] Analysis of the main reason for the above phenomenon is that the heating control technology of carburizing electric furnace is backward, and the use of leakage current to trigger thyristor conduction can only control the furnace temperature simply on and off, and cannot continuously adjust the furnace temperature

It can only be used when the temperature control accuracy and process requirements are not high

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