Plate Αnd Shell Exchangers

Shell-and-plate heat exchangers are used for heat transfer duties where pressure, temperature, or mechanical design requirements exceed the limits of a conventional gasketed plate heat exchanger. The construction combines a welded plate pack with an external shell, allowing service in steam condensation, steam heating, oil cooling, gas heating/cooling, HVAC, marine and offshore systems, food processing, biogas, pulp and paper, chemical, petrochemical, mining, and other heavy industrial applications.

Selection is based on heat duty, flow rates, inlet and outlet temperatures, allowable pressure drop, fluid type, fouling tendency, thermal cycling, differential thermal expansion, and cleaning requirements. Bolted designs provide better access for inspection and maintenance. Fully welded designs are selected where operating pressure, temperature, or compatibility with aggressive media requires a gasket-free welded construction. In fully welded units, plate pack cleaning is normally carried out by CIP, since the plate pack is not opened for mechanical cleaning.

This exchanger type is generally suited to clean fluids, demineralized water, thermal oils, steam, and other clean industrial media. In steam service, the design should account for condensate drainage, steam quality, water hammer risk, condensate-side backpressure, and control valve stability. Steam control performance also depends on correct valve sizing, turndown, actuator response, and stable condensate removal under part-load conditions.

Available Sondex/Danfoss versions are referenced with connections from DN25 to DN300, plate materials in AISI 304, AISI 316, or titanium, and shell materials in carbon steel or stainless steel, with design pressure up to 40 bar. Mechanical design and fabrication are stated in accordance with PED 2014/68/EU, EN 13445, and ASME Section VIII Division 1. The stated temperature range is typically -10 to 250 °C for bolted types and up to 400 °C for fully welded constructions, subject to material selection, design pressure, and service conditions.