general practice of steelmaking of SA-105: fine grain practice? 4

[YuJie_PV]

hi all,
it is a question about steelmaking of SA-105.
i have an experience that the SA-105 I purchased are always normalized even without prior requirement.
and what about fine grain practice? will the Steel Mill perform fine grain practice as default?
In other words, what is general practice performed to SA-105 on fine grain practice?
anyone has any steelmaking experience in this?

Thanks in advance.

 

[r6155]

Did you read SA-105 2023?

Regards

 

[Krausen]

Ah yes, welcome to the rabbit hole that is "fine grain practice".

@r6155 - Did SA-105 get updated in 2023 on this?

 

[BJI]

There is no requirement for fine grain practice in SA-105, 2023. You would have to specify in the PO for testing to determine the grain size. Figure UCS-66(e)(2) refers to SA-20, whereby SA-20 8.3.1 should give you the relevant information. Elsewhere in the world ISO 643 may also used. It may be easier to order SA-350-LF2 for low temperature applications.

 

[YuJie_PV]

Thanks for your response, Krausen,BJI
actually, i have read almost all the post related to SA-105.
i've gone through ABSA's "Information Bulletin IB20-008", and know SA-105's toughness in low temperature is not so good.
i also know how FG is defined in SA-20。
i just wonder if anyone who has worked as a steelmaker or similar experience, may share some information on how is SA-105 dealt with by its manufacturer with regard to FG, is there any routine?

please excuse my english skills.
i hope i've made myself clear.

Thanks in advance.

 

[BJI]

Could be worth posting on the 'Metal and Metallurgy engineering' forum regarding the FG processing practice, assuming grain refining elements are not used. Control of the Mn/C ratio with normalization might be sufficient.

 

[SJones]

It is more likely to be dependent upon the requirements imposed upon the steelmaker by the forging manufacturer - the latter will be responsible for working, and subsequent heat treatment. This will need the knowledge and experience to order steel that will achieve the required end result after forming and any heat treatment.

Steve Jones
Corrosion Management Consultant

http://www.linkedin.com/in/drstevejones

All answers are personal opinions only and are in no way connected with any employer.

 

[r6155]

SA-20 is for steel plates.

Regards

 

[r6155]

@ Krausen
SA-105 2023 Revised in its entirety

Regards

 

[r6155]

See thread794-486178

Regards

 

[BJI]

@r6155, UCS-66(e) applies to all material assignment notes. It simply provides a reference to fine austenitic grain size, as required under note (2)(a), to use curve B for A105N material. It doesn't matter if it is a plate specification or not.

 

[r6155]

@ BJI
USC-66 (e) say:
(e) The material manufacturer’s identification marking
required by the material specification shall not be
stamped on plate material less than 1
/4 in. (6 mm) in thickness unless the following requirements are......

But it doesn't mention the grain size.

Regards

 

[BJI]

This should be the general notes to Figure UCS-66(e) as per my original post.

(e) The following shall apply to all material assignment notes:
(1) Cooling rates faster than those obtained by cooling in air, followed by tempering, as permitted by the material specification, are considered to be equivalent to normalizing or normalizing and tempering heat treatments.
(2) Fine grain practice is defined as the procedure necessary to obtain a fine austenitic grain size as described in SA-20.
(3) Normalized rolling condition is not considered as being equivalent to normalizing.

 

[r6155]

1) SA-105 and SA-961 do not mention fine grain.
There may be an error in ASME VIII Div.1 when SA-20 is mentioned with SA-105

@TGS4: please can you send us your comment?

2) We don't know what use (OP) wants to give to SA-105: piping or pressure vessel?
3) Simpler are the SA-266 (flanges for pressure vessels) and SA-788.
4) If you require fine grain for SA-105 you must specify the grain size number in the order.
5) After all, what do you use this grain size number for?

Regards

 

[GD2]

Yujie PV,

Why are you specific about 'Fine Grain Structure' of SA-105? Are you looking for specific application of SA-105?
SA-105N is Normalized and will fall in Curve C of UCS-66.
Most EU steelmakers makes SA-105 as SA-105N as default as it will also qualify the material for NACE compliant.
Normalizing itself produces a fine grain structure that enhances strength and toughness.
If you are concerned about the MDMT/MAT of SA-105N, use Fig 66.3 to calculate the governing thickness and subsequent MDMT from Fig UCS-66.

GDD
Canada

 

[BJI]

SA-105N is Normalized and will fall in Curve C of UCS-66.

A105 produced to fine grain practice and normalized is curve B, not curve C. Since specification A105 doesn't include fine grain practice, A105N will fall under curve A. I believe this was the intent of the VIII-1 update, assuming this is the appropriate design and construction code.
Rather than testing for grain size, if not already available, directly assess the toughness by preforming impacts, or choose another material.

 

[YuJie_PV]

Thanks for all your response.
i concur with BJI.
@GD2,thanks for the information, i've found the similar phenomenon.

.
i agree, but that is not taken as "fine grain practice" as defined in SA-20.

i often deal with ASME VIII-1 vessels, in which SA-105 flange is most frequently used as nozzle flange. hence my intent for raising the question is simple, that i just like to know if "fine grain practice" as defined in SA-20 is performed as default by its fabricator, just like normalization.
i have realized that rare people here has sufficient experience to offer a direct conclusion why may vary depending on the manufacturers

Thanks.

 

[r6155]

@ YuJie_PV
I insist with my post 6Dec 23:13:35

5) After all, what do you use this grain size number for?

Regards

 

[GDHTX]

Fine grain practice is not "standard practice". Any additional requirements not explicitly mandated by A/SA105 should be specified on the purchase order.

 

[weldstan]

It depends on the manufacturer. Some routinely employ fine grain melting, at least they did in the past 20 years before my retirement 8 years ago. The vast majority of US and Europen manufacturers did not. Do not believe that fine grain melted A-105N is the equivalent of A-350-LF2.