The plate heat exchanger is a new type of heat exchanger made up of a series of corrugated metal sheets. After the plate heat exchanger has been running for a period of time, there will be deviations from the process requirements, such as an increase or decrease in pressure drop; an increase or decrease in medium outlet temperature. The method to deal with the failure of the plate heat exchanger is as follows.
1. Leakage of the heat exchanger. The leakage of the plate heat exchanger can be divided into internal leakage and external leakage.
(1) Check whether the inlet parameters of the cold and hot media are consistent with the original design values. If the inlet parameters have been changed and cannot be adjusted to the original design value, the design calculation should be re-conducted and the heat exchange area should be increased or decreased or the process combination should be changed.
(2) If the inlet parameters of the cold and hot media are consistent with the original design values, but the outlet parameters cannot reach the design values. The machine should be shut down and disassembled to check whether there is any blockage or fouling between the plates.
2. The dislocation of the plates of the plate heat exchanger is prone to plate heat exchangers that have large changes in medium flow and pressure, and are multi-pass combinations and long-term use. Leakage occurs soon after the plate is misplaced, so it must be dealt with in time. The main reasons for the dislocation of the heat exchanger plates are: the heat exchanger plates are deformed; the gasket of the plate heat exchanger slips away from the gasket groove. The deformed plate and the gasket that slipped from the gasket groove should be replaced in time.
3. When there is a lack of maintenance equipment on site, no matter whether the plates are deformed, cracked, or perforated, or the gaskets are aged or broken, they need to be replaced in time. The convenient method for on-site handling is to pull out the damaged plate and the leaking plate in pairs (A plate + B plate). If the number of plates is not too much, reducing the number of runners and continuing to use after assembly will not have a great impact on production.