1. Customer Demand Description The furnace used in industrial furnaces can be used in coking, melting, firing, rolling, heat treatment, drying, etc. according to the purpose. According to the energy classification of the furnace, it can be divided into Coal, gas, oil furnace and electric heating. As the country’s requirements for various energy-consuming enterprises in environmental protection and energy consumption reduction are increasing, many companies are forced to phase out old coal-fired heating furnaces and use heating furnaces that are heated by gas, natural gas, fuel, or electric power. Many companies have chosen heating furnaces that use natural gas or fuel as fuel, in order to improve the combustion efficiency of gas or fuel, accurately control the heating temperature, obtain good heating uniformity, achieve the highest combustion efficiency, and the best temperature control effect. It needs a stable and reliable furnace control system.
In this project, it is necessary to control a furnace that uses natural gas as a fuel. To make natural gas have a high combustion efficiency, so that the boiler temperature is controlled within the set temperature, to meet the emission reduction requirements.
2. The current control mode of the industry prior to the customer's industry is:
The furnace controller is used to control the set temperature. The intelligent control instrument has multiple temperature input and digital output functions. It can set the temperature conditions of the switch output when the temperature is higher or lower than the setting. When the temperature threshold is reached, the digital output contact is turned on or off to control the temperature. This control method is low in cost, but has poor control accuracy for temperature, low gas combustion efficiency, and poor control flexibility.
3, the program to achieve functional requirements: to achieve the "air heaters and kiln emissions standards" requirements, have a high thermal conversion efficiency; heating and insulation, the temperature changes smoothly.
System Components:
The upper computer uses an HMI to run the configuration software, and then uses the serial port and the DAM-3000 series module for data acquisition.
DAM-3058F (8-channel analog input module): Data acquisition for temperature, pressure, and other sensors;
DAM-3014D (16-channel open-collector output module): outputs of relays, solenoid valves, and signal lights;
DAM-3013D (16-channel optically isolated input module): inputs for position sensors, flame switches, etc.
The upper configuration software displays the real-time information of the status of each control point, displays the curve and historical data of each temperature and pressure test point, and can also set related parameters here.
plan description:
In order to make the temperature of the heating furnace uniform, in this solution, 16 heating points are distributed and distributed in the furnace. The 16 heating points are divided into 8 large nozzles and 8 small nozzles. The size of the nozzles is interleaved and installed in the boiler. Inside, through the control of the size of the nozzle control valve, you can adjust the heating temperature of 16 points to achieve accurate control of furnace temperature and temperature distribution requirements.
The program's control process is: First, check the fan pressure, gas pressure and air pressure, if all normal, then the ignition, through the flame switch to detect whether the ignition is successful, if not successful, close the relevant solenoid valve, if the ignition is successful, according to The difference between the set temperature value and the actual temperature value determines whether to open the large fire nozzle valve or to open the small fire nozzle valve so as to achieve the temperature control.
4, product model
HMI9910, DAM-3058F, DAM-3013D, DAM-3014D