... 2,Anti-wear 3,Lower contact resistance 4,Higher stability High-frequency welded helical finned tube is a highly efficient heat transfer, it ... steel fins wrapped heliclly around steel pipe, and continuously welded using the high frequency electric currentwelding process so as to reduce the flow ... height : 5-30mmfin thickness:0.7-3.0mmlength :0-12m high-frenquency welded helical fin tube 2012 hot product