EROSION PREVENTING DEVICE OF HEAT TRANSFER PIPES FOR BOILER

PURPOSE:To provide an erosion preventing device of heat transfer pipes for a boiler capable of preventing their erosion without deteriorating the heat absorption efficiency of the heat transfer pipes. CONSTITUTION:The heat transfer pipe coils 24 of a horizontal bank part disposed in a passage surrounded by casing side wall pipes 8 are covered with a punching plate 21 composed of a stainless or iron porous plate having crest parts and trough parts. In the trough part of the punching plate, a funnel 22 for collecting an ash content in a combustion gas is provided. In the funnel, an exhaust pipe 23 for exhausting the collected ash is provided. A metal porous plate 21a is provided at the end of the punching plate abutting against the casing side wall pipes 8 so as to partition therebetween. Thus, the gas flow velocity of the heat transfer pipe parts in which an erosion is liable to be generated is lowered and the erosion can be prevented without deteriorating a heat transfer performance.