ASTM A179 Carbon Steel Longitudinal Finned Tubes With Perforated Fins For Heat Exchangers Conventional longitudinal finned tubes are gradually being phased out of the market, though demand persists for legacy equipment applications. Perforated-fin longitudinal tubes represent an upgraded solution. Designed for high-efficiency, adaptable industrial heat exchange scenarios that push performance limits, this product improves upon traditional solid-fin designs—which often suffer