The radius is checked for its OD and wall thinning with the recommended specification 5. To avoid oxidation, inert gas (Argon) is passed through tubes ID at the required flow rate 4. U bend tubes produce will accordance to customer's drawings 3. We use Cold Drawn techonology to produce U bend tube 2. This kind of seamless tubes are have a very important position in our all products. Our heat exchanger tube with pickling and annealing surface is very popular in boilers and heat exchangers industry, water heater industry, air-conditioning industry etc. TP316L U Bend Tube With Low Price, Heat Exchanger Tube