The issue of thermal expansion of the fluid inside the heat exchanger
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In production, the problem of purging heat exchangers often arises. When the shell side of the heat exchanger is filled with water and the inlet and outlet valves are not opened, the water remains trapped in a closed environment. Purging steam at around 1.0 MPa and 180°C is introduced into the tube side, causing the water in the shell side to expand due to heat, which in turn creates pressure on the tubes. What changes will occur in the state of the water inside the shell side? To what level will the pressure rise if it expands? Can you calculate how much it is? What can be reflected in the harm to the equipment?
Liquids are incompressible; in one of our pipelines filled with alkali slag and equipped with heating, over the course of several years the gasket or cover of a valve would suddenly burst open. We never managed to figure out why this happened. It was only after one of the gaskets broke that we realized the force generated by the expansion of the liquid when it is heated after being sealed on both ends.
Check the standards for safety valves. It’s available in HG20570. There is a way to calculate this.