Chain Grate

A chain grate is a commonly used stoker grate in industrial boilers. The main structural difference between it and a belt-type grate lies in the adoption of multiple rigid crossbeams. The grate bars are installed in the corresponding clamping grooves of the crossbeams, which are fixed on the driving chains. Normally, there are two driving chains; additional chains can be installed if the grate is relatively wide, and the chains are driven by sprockets mounted on the front shaft (drive shaft).

The grate surface is generally composed of 4 to 12 parallel chains, whose structure is similar to that of a bicycle chain. Each chain is formed by connecting chain links consisting of large rings, small rings, washers, liners and other components with pin shafts. The grate bars are assembled on the chains through clamping plates, overlapping front and back, fitting tightly with each other, and arranged in a fish-scale shape as a whole. When the grate bars run to the tail of the boiler and move downward into the return stroke, they will turn over successively by their own gravity and hang upside down on the clamping plates, which can not only automatically remove residual ash and slag but also achieve self-cooling. Adjacent chains are connected by pull rods and sleeves to ensure a constant distance between the chains.

The belt-type grate is a light-duty grate suitable for boilers with an evaporation capacity below 10t/h. Its grate bars are divided into two types: driving grate bars and driven grate bars. They are connected and combined by round steel to form a wide belt, which surrounds the front sprocket and the rear roller. The driving grate bars bear the transmission of the pulling force for the movement of the entire grate, so they are thicker than the driven grate bars and are made of malleable cast iron.