When checking the delivery list, procurement personnel often find that for the same model of plate-and-frame heat exchanger, the number of plates, gasket material, and connection orientation do not match the process requirements, resulting in the need for secondary disassembly and reassembly after installation. In most such cases, the problem does not lie in the manufacturing process, but rather in insufficiently specific confirmation of the medium, temperature, and cleaning conditions during the selection stage. The following points are listed in the order of procurement verification.
Plates are commonly made of 304 or 316L stainless steel; the former is suitable for general clean water and low-corrosivity media, while the latter offers better corrosion resistance in operating conditions with lower chloride ion content. Titanium is suitable for seawater or chloride-containing media. During procurement, the supplier should be required to provide material certificates, and it should be verified whether the plate thickness corresponds to the design pressure.
The gasket is an easily overlooked part of selection, and its material directly determines the applicable media and temperature range. Nitrile rubber is suitable for water and general oils, ethylene propylene rubber has good resistance to hot water and steam, and fluororubber can cover higher temperatures and some chemical media. During procurement, the medium name, concentration, and maximum operating temperature should all be provided to the supplier, avoiding ordering based only on ambient-temperature clean water conditions.
Whether the equipment's parameter matching is reasonable directly affects the cleaning cycle and operational stability. When plate spacing, flow path combination, and flow velocity design are too conservative, fouling-prone media will shorten the interval between disassembly and cleaning. Procurement personnel may require the supplier to specify the design flow velocity and allowable pressure drop, and determine the maintenance plan in conjunction with on-site water quality or medium cleanliness.
Confirm that the connection diameter, flange standard, and nozzle orientation are consistent with the on-site piping, and also verify the equipment's overall dimensions and reserved maintenance space; insufficient reserved space will affect later plate extraction for cleaning.
During incoming inspection, verify the plate material certificates, gasket material markings, pressure test records, and spare parts list. It is recommended that gaskets be purchased with the equipment in a certain proportion to facilitate subsequent maintenance and replacement.
