METHOD AND APPARATUS FOR RELIEVING STRESS OF WELDING PART BETWEEN HEAT EXCHANGE TUBE AND HEAD OF HEAT TRANSFER TUBE IN HEAT RECOVERY SYSTEM GENERATOR

摘要

PURPOSE: To provide a method and apparatus for relieving welding stress of heat transfer tube, wherein heat treatment time and cost are reduced by partially heat treating a heat exchange tube welding part in the state that the heat exchange tube is welded to headers. CONSTITUTION: In a heat transfer tube at both sides of which headers(12) are disposed, and in which a plurality of heat exchange tubes(14) are disposed between the headers at both sides so that the heat exchange tubes are welded to the headers in the state that ends of the plurality of heat exchange tubes are inserted into the headers at both sides, the apparatus for relieving welding stress of the heat transfer tube as a heat treatment apparatus for residual welding stress of a header part of the heat transfer tube comprises a flame ejection pipe(50) an end of one side of which is formed as a closed end surface(52), an end of the other side of which is formed in an opened pipe shape such that the flame ejection pipe is inserted into the headers, and on the circumference of which a plurality of ejection holes(54) are radially formed; a heat resistant heat reserving material(60) for covering an outer part of the headers; and a flame guiding pipe(70) connected to the opened end of the flame ejection pipe to input flame into the flame ejection pipe.