Tube sheet is a plate, sheet, or bulkhead which is perforated with a pattern of holes designed to accept pipes or tubes. These sheets are used to support and isolate tubes in heat exchangers and boilers or to support filter elements. Depending on the application, a tube sheet may be made of various metals or of resin composites or plastic. A sheet tube may be covered in a  material which serves as a  barrier and insulator and may also be fitted with a galvanic . Tube sheets may be used in pairs in heat exchange applications or singularly when supporting elements in a filter.