At heat exchange stations in the chemical, HVAC, or food industries, procurement personnel often encounter external leakage or abnormally increased pressure drop after a plate heat exchanger has been in operation for some time. These problems are mostly related to insufficient verification of medium characteristics, temperature and flow rate, and pressure drop margin during the selection stage. From the perspective of procurement execution, this article summarizes several key parameters that need to be confirmed when selecting a plate heat exchanger, helping reduce operational hazards caused by selection deviations.
Procurement personnel should first obtain from the process side the complete composition, concentration, operating temperature, and whether the medium contains particulate matter. Commonly used plate materials include 304, 316L, titanium, etc., while gaskets are selected from nitrile, EPDM, or fluororubber according to the medium. If the medium is corrosive, the material corrosion resistance table must be checked to avoid leakage caused by improper selection of plates or gaskets. At the same time, confirm whether copper alloys are allowed on the medium side or whether a chloride-containing environment is present, and select titanium plates when necessary.
Selection requires clarifying the inlet and outlet temperatures, design flow rates, and allowable pressure drop on both the hot side and cold side. Taking the BR-60 model as an example, the effective heat exchange area per plate is 0.6 m², the number of plates can be adjusted within the range of 30 to 180, and the flow arrangement supports single-pass, double-pass, and multi-pass parallel configurations. Procurement personnel should confirm the number of plates and flow arrangement with the supplier based on heat exchange duty and pressure drop limits, avoiding excessive flow velocity in pursuit of compactness, which may cause the pressure drop to exceed the system's allowable value.
Plate heat exchangers require reserved space for pulling out plates for cleaning or replacing gaskets. During procurement, it is necessary to verify the interface orientation, connection sizes, and footing support method, and confirm whether there is sufficient maintenance access on site. For working conditions requiring frequent cleaning, consider adding spare plates or adopting a detachable structure. In addition, attention should be paid to the material and anti-corrosion treatment of the frame clamping bolts to adapt to humid or corrosive environments.
Overall, procurement personnel should provide the supplier with medium corrosiveness, temperature and flow rate, allowable pressure drop, and installation and maintenance requirements together, and have technical personnel complete the selection calculation, which can effectively reduce the risk of leakage and pressure drop after commissioning.
