Tube Sheet Assembly for a Heat Exchanger

Abstract

A tube sheet assembly for a heat exchanger is disclosed. The tube sheet assembly includes a plastic sheet having multiple tube-retention holes defined therein and a metal plate having multiple holes defined therein, each hole being substantially coaxial with a corresponding tube-retention hole of the plastic sheet. The metal plate is connected to the plastic sheet. The metal plate can be fabricated of, for example, steel or other metals. The plastic sheet can be fabricated of, for example, nylon, ultra-high-molecular-weight polyethylene, or polytetrafluoroethylene. Tubes can be disposed in the tube-retention holes of the plastic sheet and the holes of the metal plate. In an example, the tube-retention holes of the plastic sheet have a smaller diameter than the holes of the metal plate and the tubes contact the plastic sheet without contacting the metal plate.

what is claimed is: 
     
         1 . A tube sheet assembly for a heat exchanger, comprising:
 a plastic sheet having a plurality of tube-retention holes defined therein, wherein each tube-retention hole has a diameter substantially the same as an outside diameter of a heat-exchanger tube; and   a metal plate attached to the plastic sheet, the metal plate having a plurality of holes defined therein, each hole coaxial or substantially coaxial with a corresponding tube-retention hole of the plastic sheet.   
     
     
         2 . The tube sheet assembly of  claim 1 , wherein the metal plate is fabricated of steel. 
     
     
         3 . The tube sheet assembly of  claim 1 , wherein the plastic sheet is fabricated of nylon, ultra-high-molecular-weight polyethylene, or polytetrafluoroethylene. 
     
     
         4 . The tube sheet assembly of  claim 1 , further comprising a plurality of heat-exchanger tubes disposed through the holes of the plastic sheet and the holes of the metal plate. 
     
     
         5 . The tube sheet assembly of  claim 4 , wherein the holes of the plastic sheet have a smaller diameter than the holes of the metal plate. 
     
     
         6 . The tube sheet assembly of  claim 5 , wherein the tubes contact the plastic sheet and do not contact the metal plate.