ASTM A312 CL.1 TP316L Stainless Steel Welded Pipe EFW Pipe

ASTM A358 is a standard specification for electric-fusion-welded austenitic stainless steel pipe intended for high-temperature service. ASTM A358 this specification covers five class: class 1, class 2, class 3, class 4, class 5. Each class intended for specific applications and conditions, particularly concerning temperature capabilities and welding methods. For example, class 1 refers specifically to the pipe made from austenitic stainless steel, such as TP316L, which has excellent corrosion resistance and is often used in challenging environments. And pipe shall be double welded by processes employing filler metal in all passes and shall be completely radiographed.

Manufacturing Process

1. Material Preparation:

   • Stainless steel is sourced and cut to the required dimensions.

2. Electric Fusion Welding (EFW):

   • This process involves the use of electric current to create a weld joint between the pipe sections. The edges of the pipe are melted and fused together, providing a strong and durable seam.

3. Heat Treatment:

   • Post-weld heat treatment is often performed to relieve residual stresses and improve corrosion resistance.

4. Testing:

   • Non-Destructive Testing (NDT): Includes methods like radiographic testing (RT), ultrasonic testing (UT), and magnetic particle testing (MT) to ensure the integrity of the welds and material.
   • Hydrostatic Testing: Usually performed to verify the pressure capabilities of the pipe, ensuring no leaks occur under specified pressure conditions.

• Chemical Processing: Used in the construction of transfer piping, vessels, and reactors due to its corrosion resistance.
• Oil and Gas: Employed in pipelines and fittings, especially in offshore environments.
• Pharmaceutical Industry: Used in processes requiring high cleanliness levels and resistance to corrosion.
• Power Plants: Suitable for high-temperature applications in power generation.