Working principle of flame monitoring system in industrial oil gas dual purpose burner
When the industrial oil gas dual purpose burner stops working, as the fuel pump (fuel delivery system) of the fuel burner is driven coaxially by the burner motor and the blower impeller, as long as the fuel tank is installed correctly, even if the closing device (such as solenoid valve) fails, the fuel is still not easy to leak into the furnace. However, in a gas burner, if the shut-off device in the valve group leaks, gas may flow into the furnace when the burner is stationary, causing the burner to face the risk of deflagration during the next ignition. Therefore, the valve system of gas burners is usually equipped with a valve leakage detection device. The airtightness of the gas solenoid valve is checked every time the burner is started, and the burner can only be ignited after the inspection program is passed. The working process of the inspection device can be divided into the following steps:
(1) Vacuum pumping: In the first 2 seconds of this stage, solenoid valve V2 opens, and the pressure in the test section is balanced with the outside world (i.e. reaches a pressure free state).
(2) The pressure free state test time is 8 seconds after emptying, and the program will check whether the test section is truly pressure free and whether this state can be maintained. If the pressure rises at this point, solenoid valve V1 (valve body in the direction of airflow) leaks. At the same time, it is also necessary to check the correct operation of the pressure switch (if there is a problem with the pressure switch itself, the leak detection device will lock the equipment).
(3) Starting from the 16th second, the pressure of the test section will open solenoid valve V1 for 2 seconds. The pressure in the testing section will increase to balance with the supply pressure. The pressure switch used for detection will operate.
(4) From this point on, the pressure maintaining state test will be conducted for a 9-second leak detection in the testing section. During this period, it will be tested whether the pressure can be maintained, i.e. whether there are leaks. If the pressure drops, it indicates a leak inside the solenoid valve V2 or test section. When the second test time has passed safely, the leak detection device will be disconnected.