factory DN25 25A sch160 90 degree elbow pipe fitting 1.5D seamless A234WPB carbon steel elbow

Raw Material Verification:
Every batch of ASTM A234 WPB seamless pipe used in production is accompanied by a Mill Test Certificate compliant with ASTM A960. Upon receipt, we perform spectrochemical analysis to verify compliance with the standard's chemical composition requirements for elements like Carbon, Manganese, Silicon, Phosphorus, and Sulfur. Samples from the same heat lot undergo mechanical property testing to confirm tensile strength, yield strength, and elongation meet A234 WPB specifications (e.g., min. tensile strength 415 MPa, min. yield strength 240 MPa).

Dimensional & Geometrical Inspection:
Each finished elbow undergoes 100% dimensional inspection.

• Digital Calipers and Ultrasonic Thickness Gauges are used to precisely measure the outside diameter and wall thickness at multiple points, with particular attention to the extrados (outer bend) where thinning may occur.
• Protractors and Center-to-End Gauges verify the 90-degree bend angle and center-to-end distance.
• Out-of-Roundness Gauges check for port ellipticity.
• Weld Bevel Gauges ensure the bevel angle and land dimensions conform to welding specifications.

Surface & Non-Destructive Testing (NDT):

• Visual Inspection: A thorough examination of internal and external surfaces for defects such as cracks, seams, or laminations.
• Magnetic Particle Testing (MT) or Liquid Penetrant Testing (PT): The entire external surface, including the beveled ends, is examined using these methods to detect surface and near-surface flaws. This testing is performed by personnel certified to ASNT SNT-TC-1A Level II.
• Ultrasonic Thickness (UT) Scanning: Focused scanning is conducted on the extrados and other potential thinning areas to ensure the wall thickness meets or exceeds the design minimum.

Process Control & Verification:

• Heat Treatment Monitoring: The temperature and time curves for the normalizing heat treatment are automatically recorded and archived, ensuring process consistency and traceability.
• Hydrostatic Testing (Optional): Upon client request, individual elbows can be subjected to hydrostatic pressure testing, typically at 1.5 times the pressure rating for the applicable temperature, to validate pressure-containing integrity and leak-tightness.

Final Inspection & Documentation:
All inspection data is recorded in an Inspection and Test Plan (ITP). Products passing all checks receive a Final Inspection Release Certificate. The complete documentation package available includes: Mill Test Certificate (MTC 3.1), Dimensional Inspection Report, Non-Destructive Test Reports (if applicable), Heat Treatment Records, and Third-Party Inspection Reports (when requested by the client).

ELBOW SURFACE

Sand Blast

After hot forming, we arrange sand blast to make the surface to be clean and smooth.

After Sand blast, to avoid get rust, should do black painting or anti-rust oil, Hot dip galvanized (HDG) , epoxy, 3PE,  vanished surface, etc. That is depend on customer's request.