I would like to ask: why do the pipes vibrate severely when the heat exchanger is started?
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Initially, we used plate heat exchangers; when they were in use, there was severe steam leakage and loud vibrations in the pipes. However, with the use of a parallel heat exchanger (tubular type), there is almost no vibration, nor any steam leakage. What’s the difference? Is the loud vibrating noise a problem with that location, or is it due to steam leakage? Is it a problem with the equipment itself?
Is there water hammer? It’s unclear; it’s impossible to analyze
First, turn on the cold stream, then the heating steam. Before turning it on, drain all the condensed water from the steam pipe, and then introduce the steam slowly. Vibration is caused by water hammer.
The order is as follows: how does water hammer occur? Thank you
The flow channels in plate heat exchangers are smaller than those in tube heat exchangers; due to the larger heat exchange area, the steam that enters first will quickly form condensate, and mixing this condensate with the steam that enters later can cause liquid slugging. The main cause of leakage in plate heat exchangers is excessive temperature differences leading to uneven heating and cooling.
I took 2 photos on purpose for your reference
This device also uses this type of plate heat exchanger; plate heat exchangers indeed offer a large heat exchange area, are inexpensive, and provide excellent heat exchange performance； When this unit was put into operation with a plate heat exchanger, there was significant vibration noise in the pipes and the plate heat exchanger itself; this was actually caused by water hammer. Later, when starting up the unit, we did not turn on the circulating water, and instead used a rubber hose to drain water from the outlet of the plate heat exchanger. We then slowly opened the valve on the hot side, monitored the temperature at the outlet of the plate heat exchanger and kept it at 100°C, and based on that temperature, gradually opened both the valve on the hot side and the valve on the cooling water side ； With this approach, water hammer is essentially eliminated ； As for switching to a tubular heat exchanger, the vibration noise is lower; the main reason is that in tubular heat exchangers the heat exchange process is longer compared to plate heat exchangers, allowing for a more thorough separation of the gas and liquid phases ； Personal opinion
May I ask, for shell-and-tube condensate systems, is it located in the tube side or the shell side?
It is on the heat medium (steam) side, usually in the tube side.