... to form fins positive shap much like letter "H", so called H-fin tube. H-economizer widely used in utility boilers, industrial ... of 2-fold, an expansion of the heating surface. H-economizer flash resistance welding processes used, the welding seam after ... : carbon steel, stainless steel, Aluminium and alloy steel; Supplied H Type Fin Tube Specification Item SymbolUnitParameter ValueBare Tube ODΦmm32 ...