Abstract: Heat transfer elements are made of a polymer matrix having a fibrous material interspersed therein, the heat transfer element comprising a fluoropolymer at least on an outer surface thereof, the interspersion of the fibrous material within the polymer matrix providing rigidity to the heat transfer element. A thermally conductive material is distributed within the heat transfer element. Such a heat transfer element can be used in the manufacture of radiant panels for power generating stations or can be formed as a pipe for similar use. The heat transfer element may comprise a polymer sheet having a fibrous material distributed therein providing structural strength and a fluoropolymer at least on an outer surface of the element which protects the element from physical and chemical corrosion while providing anti-fouling properties and good flow characteristics to the element.

Abstract: An elongate tubular heat transfer element having a longitudinal tube axis that runs through the hollow interior of the heat transfer element. The heat transfer element includes a wall of monolithic construction having an outer surface and an inner surface. The wall is formed from a composite material including a matrix and rovings embedded in the matrix. The composite material is in contact with the hollow interior such that the inner surface determines a boundary of the hollow interior which extends longitudinally along the axis of the heat transfer element. The matrix is of a fluoropolymer having embedded therein rovings of boron-free chemically resistant glass fibres. The rovings include from about 20% to about 60% by volume based upon the volume of the composite material, rovings that extend longitudinally in a lengthwise direction parallel to the axis of the heat transfer element and rovings that extend spirally around the axis.