ASTM A335 P22 vs 12Cr1MoVG

[CakraMas]

Hi there,
Right now I'm supervising in designing of Steam Coal Power Plant. Based on our requirement, main steam pipe shall use ASTM A335 P22 material.

The contractor proposed 12Cr1MoVG for main steam pipe instead of our requirement.

Right now, we are debating about this material. We are debating about which one is better for main steam pipe.

Could some one help us to give the comparisson of those material ? Could you give an advice, which material is better for the main steam pipe ?

For information, temperature that will pass through the main steam pipe is around 500 C.

Thanks in advanced

[belonk_182]

In our plant using 12Cr1Mov as our HP superheater tube, but for main HP header using P22. For HP piping using P11. Temperature 510degC