An Interlock in the boiler’s control system is a programmed or hardwired condition that forces a device to be in a pre-determined or permissive state before the process can continue.
Depending on design pressure, fuel type, either liquid, gas or solid, all steam boiler require interlocks to sequence the operation and to prevent damage to the boiler. Examples of such devices are High or Low Boiler Drum Water Level, Low Boiler Feed Pump Pressure, High or Low Fuel pressure, High or Low Atomization pressure (oil fired), Proof of Ignition, Proof of Flame, FD and/or ID (solid fuel) Fan Motor Operation or combustion air pressure, Damper or Valve position and High Boiler Steam Pressure as well as O2 and furnace temperature.
The higher heating value of natural gas refers to the total heat released when a specified amount of natural gas is completely burned, including the latent heat of vaporization released by the condensation of water vapor in flue gas into water.
The lower heating value of natural gas refers to the heat released when a specified amount of gas is completely burned, the temperature of combustion products is the same as the initial temperature of natural gas, and the generated steam remains ...
ATMOSPHERIC BOILER - a boiler in which combustion air/flue gases are drawn through the boiler without a fan. Modulating atmospheric boilers are designed to control the output (size of flame) to match the boilers variable load requirements. During this process the burner is designed to stay at the correct fuel / air ratios across the complete firing range ensuring maximum combustion and boiler efficiencies. Modulation refers to a boiler's ability to match firing rate - input - to meet the heating demand - output - of the system. (https://tlj-eng.com/news/heating-boilers-what-you-need-to-know.html)
First of all, don't panic. According to the normal shutdown sequence, check whether the fuel, steam and water valves of gas-fired boiler meet the shutdown requirements.
Secondly, close the surface blowdown valve of the gas-fired boiler to prevent other faults of the boiler. Then, quickly close the main steam valve to prevent the gas boiler drum from losing water.
Thirdly, close the deaerator air supply valve, the main power switch and the natural gas valve. The air inlet of the gas-fired boiler burner should not be blocked to reduce the area of the air inlet, and the room ventilation should not be blocked to avoid the formation of toxic and harmful gases.
Manually close the fuel supply valve, stop the combustion, purge after the program enters, until the end of the purge, stop the program such as burning heavy oil, and enter the line sweeping stage before stopping the combustion, and purge with steam or light oil pipe; Generally, steam purging is used when stopping for a long time.
Recently, some users have come to consult how to solve the ash leakage at the expansion joint of boiler flue outlet. ZOZEN Boiler suggested that in case of ash leakage from the expansion joint at the boiler flue outlet, please contact the professional industrial boiler manufacturer.
Boiler safety accessories are indispensable parts of boiler operation, mainly refer to accessories such as pressure gauge, water level gauge, safety valve, steam-water valve, sewage valve, etc. These accessories are extremely important to the safe operation of boilers, especially pressure gauges, water level gauges and safety valves, which are the basic accessories for ensuring the safe operation of boilers. Therefore, they are often referred to as three safety accessories of industrial boilers.
