What Are The Types Of Boiler Grates And Their Applications?

A boiler grate is the part of a boiler or industrial furnace used to contain solid fuel and burn it efficiently. The whole grate mainly includes two parts, the frame and the grate piece. Grates are usually made of cast iron. After the assembly is completed, the necessary ventilation gaps are maintained between the parts, and an independent ventilation room with adjustable air volume is usually set up under the grate, so that the air can enter the fuel layer through the gaps for combustion. After burning, the ash is discharged manually or mechanically. The grate has fixed type, mobile type, reciprocating type, vibration type and bottom feeding type.
The first is the grate boiler grate. The grate boiler grate is generally in the shape of strips or plates, and is fixed and installed on the bottom of the furnace or combustion chamber by the surrounding frame. This kind of fire grate can only add coal and slag artificially on a regular basis, the operation labor intensity is high, and the combustion economic effect is also poor.
The second is the mobile boiler grate, which has two types: chain belt type and chain type. The grate surface of the chain grate is the chain itself; and the grate of the chain grate is fixed on the bracket or bracket on the upper part of the chain. Both the chain grate and the chain grate are driven by the sprocket, which makes the grate move slowly. The coal falls evenly onto the grate from the coal hopper at the front end of the grate. The thickness of the coal seam is adjusted by the coal gate which can be lifted up and down. As the grate moves back, the coals ignite, burn and burn out. There is also a coal thrower that does not use the coal hopper to feed the coal, but throws the coal to the rear of the grate, and the grate moves forward. The speed of the grate is adjusted through gear transmission according to the type of coal and boiler load. The chain grate has reliable operation, stable combustion and wide fuel adaptability, and is widely used in industrial boilers.
There are also reciprocating boiler grates, which are composed of a set of fixed grate pieces and a set of reciprocating movable grate pieces, which are divided into two types: stepped type and horizontal type. The reciprocating motion of the movable grate piece gradually pushes the coal seam to the rear for combustion, so this kind of grate has wide adaptability to coal types. There is a small inclination between the vibrating grate surface and the horizontal plane, and the grate vibrates regularly under the action of the motor and eccentric wheel. During the vibration process, the fuel layer continuously moves to the rear of the furnace, causing the burnt ash to fall into the ash pit at the end of the grate. The grate is characterized by a simple structure.
Finally, there is a boiler grate with a trough structure. The bottom of the trough-shaped boiler grate is equipped with a screw rod, which leads to the coal scuttle outside the furnace. Coal is fed into the coal tank from the lower part of the coal hopper through the screw, and enters the high-temperature combustion zone from bottom to top. When the ash exceeds the accumulation angle, it is discharged to both sides by gravity. This kind of grate has a simple structure, but it has certain requirements on the particle size and humidity of the coal, and is generally only suitable for small industrial boilers with an evaporation rate of less than 1 ton/hour.
These types of grates are common types, because of the difference in structure and function, they are applied in different scenarios.