Carbon Steel Seamless Pipes — ASTM A106, A53 & API 5L

What is a Carbon Steel Seamless Pipe?

Seamless pipe is formed by piercing a solid billet and rolling or drawing it into a hollow, so there is no longitudinal weld. Because the wall is uniform and weld-free, it is the default choice for high-pressure and high-temperature carbon steel lines, such as steam, hot oil and process piping designed to ASME B31.1 or B31.3. ASTM A106 covers high-temperature service, ASTM A53 covers general pressure and mechanical use, and API 5L covers line pipe for oil, gas and water transmission. Wall thickness follows ASME B36.10M schedules.

Key features

• Stockist and supplier — sourced from established seamless mills, not manufactured by Teshi
• Grades: ASTM A106 Gr A/B/C, ASTM A53 Gr A/B Type S, API 5L Gr B and X-grades
• Wall thickness to ASME B36.10M schedules (SCH 10 to XXS) and STD/XS weights
• Plain, bevelled or threaded ends as ordered
• Heat-number traceability from the mill certificate to each length
• Pipes can be ordered together with Teshi-manufactured flanges and butt weld fittings

Specification

Applications

• Steam and condensate lines in power and process plants
• Refinery and petrochemical process piping (ASME B31.3)
• Oil and gas gathering and transmission lines (API 5L)
• Boiler feed water and high-temperature utility piping
• Hydraulic and high-pressure lines in heavy industry

Seamless vs ERW pipe

Seamless pipe has no weld seam, so it carries no weld-joint factor and is preferred for high-pressure, high-temperature and sour or cyclic service. ERW pipe is made from coil with a single electric-resistance weld; it is usually more economical, has tighter wall-thickness tolerance and is widely used for water, gas distribution, structural and utility lines. Where the design code and service allow, ERW can replace seamless in smaller and medium sizes.