Seamless Steel Tubes (SMLS Steel Tubes), Seamless Steel Pipes Heat Exchanger Tubes and Condenser Tubes. Size: Outside Diameter: 1/2″ – 4″, Wall Thickness: 1mm – 10mm. Standard: ASTM/ASME A/SA179, BS3059 PART II. Application: used for Air Cooled Heat Exchangers, Water Cooled Heat Exchangers, HRSG, Shell and Tube Heat Exchangers.   Boiler Pipes, Boiler Tubes Size: Outside Diameter: 6.0mm – 219mm, Wall Thickness: 1mm – 30mm. Standard: ASTM A210 A1, C, ASTM A192. Application: used for High Pressure Boiler Pipes, Boiling Water Tubes, Superheater Pipelines, Flue Tubes, Small Flue Tubes, and other Pressure Tubes.   Seamless Low Temperature Tubes and Pipes Size: Outside Diameter: 10mm – 340mm, Wall Thickness: 1mm – 30mm. Standard: ASTM/ASME A/SA334 GR.1, GR.6, GR.8. Application: used for Low Temperature Machines and Pipelines.   Seamless Carbon and Alloy Steel Mechanical Tubing Size: Outside Diameter: 6mm – 340mm, Wall Thickness: 1mm – 30mm. Standard: ASTM A519, ASTM A513, DIN2391, JIS G3454. Application: used for Mechanical Tubing, Air Cylinder Tubes and Pipes, Oil Cylinder Tubes and Pipes.   Seamless Carbon Steel Tubes & Pipes Size: Outside Diameter: 21.3mm – 610mm, Wall Thickness: 1mm – 30mm. Standard: ASTM A106 A53 API 5L GR. B (Grade B). Application: used in General Structure and Mechanism, including Construction, Machinery, and Transportations, e.g. Fluid Tubes.   OCTG Tubes (Tubing and Casing) Size: Outside Diameter: 7 – 9 5/8inch (177.8 – 244.5mm), Wall Thickness: 5.9mm – 14.1mm. Standard: ASTM A106 A53 API 5L GR. B (Grade B). Application: used in Oil Well Extracting Petroleum or Natural Gas.