Plate Heat Exchangers Gold-Bar Engineering ltd., specialises in the design, supply and assembly of Sondex Ltd Gasketed Plate Heat Exchangers, Semi-Welded Plate Heat Exchangers, Free Flow Plate Heat Exchangers and Brazed Plate Heat Exchangers. Complete Systems Plate Material is AISI 316 or AISI 304. A variety of gaskets are snapped on or glued on plates:Nitril, EPDM or Viton. Frames are made in Carbon Steel or Stainless. All surfaces in contact with plates are 100% SS.