which standard can be used for non-metal inclusion of P22 steel piping 1

[terry8u8]

there is no requirement for non-metal inclusion in ASTM A335,But I think P22 steel pipe should have some restriction of non-metal inclusion . If I want to put some restriction on technical specification of P22 steel pipe , what is reference standard I can use ?
P22 steel piping is used for main steam piping of thermal power plant .

 

[metengr]

If you specify SA 335 material specification you can invoke Supplemental Requirement S4 in your PO. You can agree on extent and type of coverage. Also, review, SA 530. This is actually addressed in section 26 for Government Procurement, specifically 26.1.10 and could be specified by you for the UT examination.

 

[deadrange]

What Metengr suggests is for large macro inclusions. S4 in SA 335 and A 335 are define requirements for Macro Etching a transverse section. THis test in my opinion is not great for non-metallic inclusions. A better test would be something along the lines of ASTM E45. I am not sure what kind of limit you would put on this application, but it would give a better representation of microcleanliness.

UT testing is also a good alternative. It will catch the larger non-metallics

 

[metengr]

Yes, of course, I was thinking in terms of laminations because it makes no sense in my mind to worry about non-metallic inclusions in piping when spools are welded in the shop and in the field.

Why would one drive unnecessary cost into specifying any supplemental tests for non-metallic inclusions when this grade of piping supplied under SA 335 has been successfully used in the Power Generation sector for years and years? Your weak links are still welds, not seamless base material made to this specification.

 

[terry8u8]

UT testing is also a good alternative. It will catch the larger non-metallics

But I think UT test in A335 is mandatory, so there is no need to do more
The reason for I want to put some restrict oninclusion is that mechanical property is not stabled and some experts don’t satisfy mechanical property of pipe manufactured by this plant.They suggest controlling non metal inclusion.

 

[metengr]

The reason for I want to put some restrict oninclusion is that mechanical property is not stabled and some experts don't satisfy mechanical property of pipe manufactured by this plant.They suggest controlling non metal inclusion.

Look for another pipe supplier if they cannot produce pipe to the SA 335 material specification. There is no reason to go down the path for controlling non-metallic inclusions for reputable mills that supply this common grade of seamless pipe.

 

[terry8u8]

Yes , that is the best way .
But we need to consider the price, that is why we still choose them as supplier.