Friction-free grate device

The utility model discloses a friction-free grate device for a grate type boiler. The friction-free grate device consists of fixed grate segments, water cooled tubes, movable grate segments, connecting pieces, an inclined vehicle, a chain, a chain wheel, a counterweight, wheels, a rail, a push-and-pull rod and a driving mechanism, wherein the fixed grate segments are overlapped with the water cooled tubes communicated with air preheater tubes of an air blower, so that functions of erecting and cooling the fixed grate segments are realized; each movable grate segment penetrates through a gap between two corresponding layers of fixed grate segments; the tail ends of the movable grate segments are fixed on the inclined vehicle through the connecting pieces; a head end of the inclined vehicle is connected with the counterweight through the chain and the chain wheel; the weight of the counterweight is used for canceling the downslide force of the inclined vehicle; and a tail end of the inclined vehicle is connecte