The Description Of Traveling Grate

Traveling grate constructions known in the art have side plate members slidably guided within a stationary grate casing at their upper and lower edges. The upper edge of each side plate member is guided by a stationary upper slide rail, whereas the lower edge of the side plate member is supported by a sealing strip pushed upward by means of a spring. The side plate members of traveling grates are frequently subjected to very high temperatures because of the material located on the grate or because of the means of treatment (e.g., hot gases). Therefore, the side plate members are frequently subjected to a strong thermal expansion while the stationary grate casing undergoes comparatively little thermal expansion because of its substantially lower thermal load. Since the known construction prevents the downward movement of the sealing strip, possibly because of material located under it (caused by the vertical expansion of the side plate member), it is necessary to provide a comparatively large clearance between the side plate member and the upper stationary slide rail in its original (cold) state, in order to avoid jamming effects. However, this results in an increased loss of material and gas at that crack, with all the resulting difficulties.

A further disadvantage of the known traveling grate construction is the fact that the springs pressing against the sealing strip from below also must absorb the entire weight of the side plate members, in order to produce sufficient sealing pressure at the upper slide surface. Accordingly, the springs must be of extraordinarily strong construction. Finally, a further disadvantage is the comparatively poor access to such springs.

An object of the present invention is to avoid these aforementioned deficiencies of known constructions by providing a traveling grate of the type referred to and wherein a particularly reliable, trouble-free operating seal is provided.

Since the traveling grate according to the invention no longer provides a seal directly at the upper and lower edges of the side plate members, but rather along the two outwardly directed flanges of the side plate members, the sealing zones are further removed from the high temperature region. Consequently, the resultant thermal expansions and the difficulties connected therewith are considerably less in the sealing zones.

Furthermore, the distance between both flanges and thus the distance to the two sealing surfaces in the embodiment according to the invention is considerably smaller than the total height of the side plate member (i.e., considerably smaller than the previous distance of the sealing surfaces). Also for this reason, considerably less thermal expansion occurs between the two sealing surfaces when the traveling grate of the invention is used.

Since the lower flange is carried by a stationary slide rail and the sealing strip is supported by the upper flange when under spring pressure, the springs are not subjected to the weight of the side plate members, but merely need to produce the sealing pressure within the range of the sealing strip. As a result, they can be made with comparatively small dimensions and are at the same time easily accessible at the new point of installation.