BS 1565-1:1949

Seven sizes in two grades, maximum working heads 60 ft and 30 ft. Minimum thickness of material, minimum heating surfaces, methods of manufacture, radius of curvature, bolted ends and handholes, method of galvanizing, screwed connections for pipes and for auxiliary electric heating. Test requirements for primary heaters and complete cylinders. Marking. Dimensions in a table, drawings illustrate method of measuring. See BS 417, BS 699, BS 1566.