... Alloy steel 3.Diameter:25,32,38 or requested Heat Exchanger Finned Tube 1.Bare tube size: OD25mm-OD160mm ... types of lathe.7.Surface finish processpolishing, sand blasting, heat treatment, painting, powder coating, anodizing, electroplating, mirror polishing ... service available.9.Productall kinds of heat resistant steel casting10.AdvantageGood quality and strict delivery time. heat exchanger finned tube