Characteristics of cast iron grates

Cast iron:

Good wear resistance: for example, during the operation of the grate, in long-term contact and friction with fuel and other materials, the cast iron surface can resist wear to a certain extent and maintain a relatively good working state. For example, common grey cast iron grates, when used in small chain grate boilers and similar equipment, can work for a long time under normal working conditions without serious wear failure.

Good vibration damping: it can absorb and buffer the vibration and impact generated during operation, which is important for a component such as the grate that needs to run smoothly and avoid problems such as loosened connections caused by vibration. For example, when the grate motor starts, stops or the load fluctuates, the cast iron grate can maintain the stability of the overall structure thanks to its good vibration damping.

Good machinability: it can be machined conveniently, so that the cast blank is machined into a finished grate that meets precise dimensional requirements and surface quality, which is helpful for the subsequent installation and commissioning work.

Relatively low strength: however, its compressive strength is still acceptable, and it can meet the needs of some working conditions in terms of bearing a certain fuel weight and the pressure inside the furnace, but its tensile strength and toughness are somewhat worse than those of cast steel, so it has certain limitations in application scenarios of large grates that bear relatively large tensile forces and impact forces.

Limited heat resistance: when used for a long time in a high-temperature environment, cast iron may develop problems such as growth and deformation; for example, in large industrial boiler grate applications at high temperature and high pressure, if the temperature continuously exceeds its suitable range (such as ordinary grey cast iron above about 800℃), its performance will drop noticeably.

Composition: it mainly consists of iron, carbon and some impurity elements such as silicon, manganese, sulfur and phosphorus. Among them, the carbon content is relatively high, generally around 2%-4%, which gives cast iron good casting performance, so that it can be cast relatively easily into grate parts of various complex shapes.