SUPPORTING STRUCTURE ALLOWING OF FREE EXPANSION OF MATERIAL RETURNING DEVICE AND MATERIAL RETURNING LEG

A supporting structure allowing of free expansion of a material returning device (10) and a material returning leg (11) comprises a material returning device framework (20) connected fixedly with the material returning device (10), a material returning leg bracket (30) connected fixedly with the material returning leg (11), several smooth steel plates (40) connected fixedly with the material returning device framework (20) and the material returning leg bracket (30) respectively, as well as a first steel plate (51) and a second steel plate (52) with self-lubrication material layers (53) on their surfaces. The first steel plate (51) and the second steel plate (52) are arranged on a boiler steel frame (50) respectively. The material returning device framework (20) is placed on the first steel plate (51) through several smooth steel plates (40), and the material returning leg bracket (30) is placed on the second steel plate (52) through several smooth steel plates (40). The smooth surfaces of the smooth steel plates (40) are placed toward and in contact with the self-lubrication material layers (53) on the surfaces of the first steel plate (51) and the second steel plate (52), such that the smooth steel plates (40) can slide on the first steel plate (51) and the second steel plate (52). The material returning device (10) and the material returning leg (11) are supported independently on multiple points in a slideable way, hence the expansion difference between them in horizontal direction can be eliminated. Une structure de support permettant l'expansion libre d'un dispositif de retour de matériau (10) et d'une jambe de retour de matériau (11) comprend une structure de dispositif de retour de matériau (20) raccordée fixement au dispositif de retour de matériau (10), un support de jambe de retour de matériau (30) raccordé fixement à la jambe de retour de matériau (11), plusieurs plaques d'acier lisses (40) raccordées fixement à la structure de dispositif de retour de matériau (20) et au support de jambe de retour de matériau (30), respectivement, ainsi qu'une première plaque d'acier (51) et une seconde plaque d'acier (52) comprenant des couches de matériau autolubrifiantes (53) sur leurs surfaces. La première plaque d'acier (51) et la seconde plaque d'acier (52) sont disposées sur un châssis de chaudière en acier (50), respectivement. La structure de dispositif de retour de matériau (20) est placée sur la première plaque d'acier (51) au moyen de plusieurs plaq