Add:Yantun, Paoai Village, Wafangdian City, Liaoning Province, China
What are the types of boiler grate?
Feb 23,2023
The boiler grate is a part of the boiler or industrial furnace, which is used to contain solid fuel and effectively burn solid fuel. The whole grate mainly consists of two parts: frame and grate plate. The grating is usually made of cast iron. After assembly, necessary ventilation clearance shall be maintained between parts. A ventilation chamber with adjustable air volume shall be set under the grate to allow air to enter the fuel layer through the clearance for combustion. The burnt ash shall be discharged manually or mechanically. There are fixed grate, mobile grate, reciprocating grate, vibrating grate and blanking grate. The following describes the types of boiler grate:
1. Grate plate boiler grate. It is generally in the form of strip or plate, and is fixed at the bottom of the furnace or combustion chamber through the shell. This grate can only be manually added coal and slag on a regular basis, with high labor intensity and poor combustion economic effect.
2. Mobile boiler grate can be divided into two types: chain belt type and chain type. The grate surface of chain grate is the chain itself; The grate plate of the chain grate is fixed on the upper bracket of the chain. Both chain grate and chain grate are driven by chain wheel to make the grate move slowly. The coal falls evenly on the grate from the coal hopper in front of the grate. The thickness of the coal seam is adjusted by the up and down coal gate. When the grate moves backward, the coal will ignite, burn and burn out. In addition, instead of using a coal hopper to feed coal, a coal dispenser is used to throw the coal to the rear of the grate. The grate moves forward. The grate speed is adjusted by gear transmission according to the coal type and boiler load. Chain grate has been widely used in industrial boilers due to its reliable operation, stable combustion and wide fuel adaptability.
3. Reciprocating boiler grate. It consists of a set of fixed grate plates and a set of reciprocating moving grate plates, which are divided into ladder type and horizontal type. The reciprocating motion of the moving grate will gradually push the coal seam to the rear for combustion, so this grate has wide adaptability to coal types. There is a small inclination between the surface of the vibrating grate and the horizontal plane. The grate vibrates regularly under the action of the motor and eccentric wheel. During the vibration process, the fuel layer continuously moves towards the rear of the furnace, so that the burnt ash falls into the ash pit at the end of the grate.
4. Boiler grate with channel structure. The bottom of the channel structure grate is equipped with a screw, which leads to the coal hopper outside the boiler. The coal is sent to the coal storage tank from the lower part of the coal hopper through the screw, and enters the high-temperature combustion area from the bottom to the top. When the ash exceeds the stacking angle, the ash is discharged to both sides by gravity. This type of grate has a simple structure, but has certain requirements for coal particle size and humidity. It is generally only applicable to small industrial boilers with evaporation capacity less than 1 ton/hour.
Boiler grate: chain grate is a widely used mechanized combustion equipment in industrial boilers, but it has a certain range of coal. Its combustion mode is moving fire bed combustion, and the fuel ignition condition is "limited ignition". The fuel enters the grate through the coal hopper. As the grate moves, the combustion process begins in the furnace. The burnt coal slag is discharged to the slag well at the end of the grate with the movement of the grate. Therefore, compared with reciprocating furnace, vibrating furnace and fluidized bed furnace, chain grate has higher requirements for coal quality. The mechanical spreader stoker is basically a stratified combustion grate with infinite ignition, which has relatively wide adaptability to coal quality.
What is the basic knowledge of boiler grate?
