Grate for a firing system

A grate for a firing system, with at least one grate conveyor having a plurality of fixed bar rows and moving bar rows alternating in the longitudinal direction, which are limited on both sides by side walls and which are composed of liquid-cooled grate plates, said grate plates being provided with a multiplicity of orifices or slits, arranged in groups, for the supply of primary air and each being pivotably connected respectively to a fixed and a movable grate plate carrier in the region of their rear end and resting with their front end on the adjacent grate plate, the grate plates of a grate plate row being connected in each case by connection means arranged underneath these, in such a way that adjacent grate plates are displaceable relative to one another to a limited extent in the grate longitudinal direction and are pivotable to a limited extent with respect to the grate plate carrier assigned to them, wherein there are provided, on the underside of the grate plate, cooling ducts which are located between the orifices or slits, these cooling ducts being formed, on the one hand, by the grate plate itself and, on the other hand, by hollow profiles attached to the grate plate.