Difference between AP Tube and BA Tube
What is AP and BA?
AP Tube is an abbreviation for Annealing Pickling Tube. BA Tube is an abbreviation for Bright Annealing Tube.
The difference between AP Tube / Annealing Pickling Tube and BA Tube / Bright Annealing Tube is Heat Treatment process.
How to AP Annealing Pickling?
After solution annealing of natural gas, pickling is required to remove the black oxide scale on the inside and outside of the stainless steel pipe, and the surface of the finished product will be sour white.
How to BA Bright Annealing?
Bright Annealing finished in bright annealed in Nitrogen and Hydrogen, without oxide scale on the surface and does not require pickling. The surface of the bright annealing tube will show the original color of stainless steel.
Stainless Steel AP Tube Specification:
Bright Annealing Stainless Steel Tube Specification
ASTM A213/A213M Standard Specification for Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes
ASTM A312/A312M Standard Specification for Seamless, Welded, and Heavily Cold Worked AusteniticStainless Steel Pipe
United States: ASTM A213 / A269 / A312 / A632
Europe: DIN 17458 / ISO 1127