Abstract: To cool a grate having alternately fixed and movable rows (1, 1′) of grate bars (2), cooling liquid is sprayed into cavities (7), open at the bottom, of the grate bars (2) from spray tubes (10) situated in the underblast region (8) and in the process vaporizes essentially completely, so that the heat of vaporization is extracted from the grate bars (2). The angle sector (12) into which the cooling liquid is sprayed may be set in such a way that in each case only those sections of the grate bars (2) whose top sides form the free surface of the grate are sprayed. The cavities may also be closed except for a discharge opening leading into the underblast region and may be connected to a supply reservoir, in which the liquid is kept at a constant level, which is just below the discharge openings.

Abstract: A grate for a firing plant, having at least one grate track with a plurality of fixed and moving rows of grate-lining units, which rows alternate in the longitudinal direction, are bounded on both sides by side walls and are provided with cooling passages as well as with feed and discharge lines. The grate-lining units are connected at their rear end to a fixed or movable grate-lining bearer and rest with their front end on the following grate-lining unit, and the cooling passages being arranged essentially transversely to the longitudinal direction of the grate. The cooling passages are tubes arranged in a meander shape and integrally cast in the grate-lining units and whose spacing is adapted to the thermal loading on the grate-lining units. The tube spacing preferably decreases from the rear end to the front end of the grate-lining unit.