A plate-shell heat exchanger consists of a plate bundle and a shell. The plate bundle is made of stamped stainless steel plates assembled and welded in pairs, and is placed as a whole inside a cylindrical shell. Compared with shell-and-tube exchangers, under the same heat exchange duty, plate-shell exchangers usually provide a larger heat exchange area per unit volume, so the equipment length and footprint may be smaller. For procurement personnel, if on-site space is limited and the cleanliness of the medium is controllable, a plate-shell exchanger is one of the options to consider.
Detachable plate heat exchangers rely on gaskets to achieve sealing between plates. They are easy to disassemble and assemble, but the gaskets are limited in temperature and pressure resistance. The BRQ-25 plate-shell heat exchanger uses a fully welded plate bundle with no gaskets, and its applicable temperature range can be extended to below 400°C and a design pressure not exceeding 4.0 MPa. Its cleaning requires chemical circulation or special tooling, which is not as convenient as detachable types. During procurement, it is necessary to weigh sealing reliability against later maintenance costs.
The corrugated structure of the plates in a plate-shell heat exchanger can promote fluid turbulence, and the heat transfer coefficient is usually higher than that of a shell-and-tube exchanger. Taking water-to-water heat exchange as an example, the heat transfer coefficient can reach 3000~6000 W/(m²·K). However, the pressure drop also increases accordingly, so the margin of the pump or fan must be calculated. If the process allows a relatively high pressure drop and pursues a compact structure, the plate-shell type has advantages; if pressure drop is sensitive, it should be reevaluated.
This model can be used in HVAC, chemical processes, waste heat recovery, and other occasions. The plates are commonly made of 304 or 316L stainless steel, and the shell is made of carbon steel or stainless steel according to the medium. During procurement, the medium composition, temperature, pressure, and flow rate should be provided so that the number of plates and the flow arrangement can be calculated. During operation, it is recommended to monitor the inlet and outlet pressure difference and clean it promptly when the pressure difference rises, so as to avoid channel blockage.
