The control system regulates and controls the flow rates of gas pipelines, flue gas, and dilution air by monitoring furnace temperature and pressure; it also incorporates a rapid shut-off device for the main natural gas line. The system employs zoned temperature control, with thermocouples installed in each zone and temperature data centrally tracked and recorded by a multi-point recorder; furnace pressure is automatically regulated via pressure transmitters and a chimney damper actuator.
Temperature control is achieved through a closed-loop system comprising intelligent digital temperature controllers, temperature sensors, and automatic burners. This system automatically calculates, executes, displays, and stores heat treatment process curves, enabling full-process control. The instrument cabinet displays operating parameters-including temperature, furnace pressure, and data for individual burners and pipelines-and features alarms for anomalies alongside emergency protection measures; pressures in the combustion air and fuel lines can be preset and automatically adjusted to ensure optimal combustion efficiency.
A PLC pulse controller and proportional combustion control valve are used to implement high/low-fire pulse control, achieving a turndown ratio of up to 1:10.
