1. What is the purpose of galvanized welded pipe?
Galvanized coating prevents rust and corrosion. Used for:
Fire fighting pipelines
Water supply
Conduit and structural pipes
2. What is black welded pipe?
Black pipe is uncoated welded pipe, usually in original steel color. Used for gas, steam, structure, and processing.
3. What causes weld defects in ERW pipes?
Common causes:
Unstable welding temperature
Poor edge trimming
Inappropriate forming speed
Impurities on the strip surface
4. What inspections are required for welded pipes?
Common inspections:
Visual inspection
Dimensional check
Hydrostatic test
Ultrasonic testing (UT)
X-ray testing (RT)
Mechanical property test
5. What is hydrostatic testing?
It fills the pipe with high-pressure water to test leakage, pressure resistance, and structural stability.
