| 摘要 |
In order to protect, with a simple structure, heat transfer tubes of a heat exchanger from wear, corrosion, and the like due to combustion exhaust gas blown onto the heat transfer tubes, a protector (12A) comprises a plurality of main protectors (12a) that cover the surface of a heat transfer tube (10) facing the upstream side of a combustion exhaust gas flow channel along the direction of the longitudinal axis and that are disposed so that an expansion allowance gap (E) is interposed therebetween, and an intermediate protector (12b) that covers a portion of the heat transfer tube corresponding to the expansion allowance gap (E) between the main protectors (12a) from the upstream side of the combustion exhaust gas flow channel. One end of the intermediate protector (12b) in the direction of the longitudinal axis encloses, so as to be able to slide in the direction of the longitudinal axis, the external circumferential face of an end part of at least one of two main protectors (12a) that are opposite to each other across the expansion allowance gap (E). The one end of the intermediate protector (12b) in the direction of the longitudinal axis serves as a connecting body to connect with an end part of the main protector (12a), and the other end of the intermediate protector (12b) encloses, so as to be able to slide in the direction of the longitudinal axis, the external circumferential face of an end part of the opposite main protector (12a). |
