DETECTING METHOD OF LEAKAGE PIPE OF MULTIPIPE HEAT EXCHANGER, CLOTH FOR DETECTION OF LEAKAGE PIPE OF MULTIPIPE HEAT EXCHANGER, DETECTION AGENT FOR DETECTION OF LEAKAGE PIPE OF MULTIPIPE HEAT EXCHANGER, AND SUBSTRATE FOR DETECTION OF LEAKAGE PIPE OF MULTIPIPE HEAT EXCHANGER

摘要

PROBLEM TO BE SOLVED: To specify a leakage pipe, by sticking a cloth on the outside surface of both pipe plates to which both ends of a cooling pipe are fixed, in the state that the outside of the cooling pipe is in a normal pressure state or a low pressure state, spreading detection agent on the cloth, reducing pressure before or after the detection agent is spread when the outside of the cooling pipe is in a normal pressure state, and detecting change of the cloth. ;SOLUTION: The protruding amount of a cooling pipe 5 from the outside surface of a pipe plate 3 is set to be 0mm. Cotton nonwoven fabric (weight 80g/m²) of about 20cm20cm is stuck on the outside surface of the pipe plate by impregnating the fabric with water. By operating a vacuum pump 9, the external part of the cooling pipe 5 is adjusted to be 40mmHg. In this state, 0.1% aqueous solution of food dye red no.106 is sprayed on the whole cloth with a sprayer. After about one minute, it can be observed with naked eyes that a radial pattern is generated around the cooling pipe 5 wherein small holes 6 are formed, as a center. Thereby a cooling pipe wherein leakage is generated can be specified.;COPYRIGHT: (C)1998,JPO