Why is it necessary to introduce the cold flow first and then the hot flow when starting up the heat exchanger equipment?
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This post was last edited by subway123 on 2011-12-26 at 19:54. Please explain why, when putting cold-exchange equipment into operation, the cold flow should be introduced first and then the hot flow.
When putting cold exchange equipment into operation, normal-temperature media should be used first, followed by non-normal-temperature media. That is, when exchanging heat at normal temperature and low temperature, start with the normal temperature side first, and stop with the low temperature side first ； When exchanging heat between normal temperature and high temperature, start with the normal temperature side first, and stop with the high temperature side first when shutting down ；
The reason is simple: to prevent thermal expansion and contraction. When shutting down the system, stop the hot medium first, and then the cold medium.