code case 2506 the 16mnr 1

[knstar]

code case 2506 the 16mnr is considered curve a.
if the 16mnr is normalized that maybe considered curve b as per the note of the ucs 66 fig.
please help me, how can i prove all above is right

 

[metengr]

This is an ASME B&PV Code case, and pertains to the use of 16MnR pressure vessel steel plate under Chinese Standards. This material is considered as P-No 1 material for the purpose of PWHT. Under subsection (e) of Code Case 2506-1, this material shall be considered under Curve A for the purpose of impact requirments.

Please obtain a copy of this code case to prove your point.

 

[knstar]

thanks for your reply.the ucs 66 note (b)(2) which describe
as the matel considered curve a shall be considered curue b if it has been normalized. and the 16mnr is considered curve a as per code case 2506.

all above is just like what i have right at 28 Apr 08 5:37 .

 

[knstar]

thanks for your reply.the ucs 66 note (b)(2) which describe
as the matel considered curve a shall be considered curue b if it has been normalized. and the 16mnr is considered curve a as per code case 2506.

all above is just like that i have right at 28 Apr 08 5:37 .

 

[metengr]

No, knstar read the Code case. ASME B&PV Code Cases are sometimes written with specific exceptions or requirements, which may go above and beyond existing Code rules. The reason for this is because of a lack of expierence with the proposed material. This is why they are called code cases.

 

[knstar]

oh thank you,

i know what's your mean.

but the question has been answered by asme expert on the seminar of shanghai at 2007 .


??1-10? GB6654?16MnR?? code case 2506????????P-No.1????UCS 66.1 Curve A?????????????????????MDMT??????????csc-66???D??????????????
In code case 2506, GB6654 16MnR has been accepted as P-No.1. For purpose of post weld heat treatment, it is considered that Curve A in UCS 66.1 fits for P-No.1. When taking into account impact test requirement, is it possible to reduce the MDMT using the ratio of stress? Or is it possible to use curve D in accordance with the fact that 16MnR is normalized?
Answer: Yes the provisions given in UCS-66(b) may be used to further reduce the MDMT from Fig. UCS-66. In addition if this material is produced to fine-grain practice and normalized it may be assigned to Curve B.0 Z% R$ w4 i: Y; N/ u
???????UCS-66(b)?????????????UCS-66????MDMT????????????????????????B?

but i don't know who can prove it correct and i don't know who make the answer for the quetion 1-10.

 

[knstar]

i think your answer is enough for my question.

maybe the 16mnr(normalized) maybe considered curve b in the new adden or the new edtion.

but it is difficult now.

else, i think the lowest tempreture equal the max. thickness is 0.394 in the ucs 66 fig. but AI tell me the max. thickness should be considered as 0.375 as per the ucs 66 tab.

and i find out the code and books about the ucs 66 fig.

the result is the max. thickness is 3/8(0.375) in.

and i want to know the max. thickness in your meaning.

 

[metengr]

knstar;
The exemptions for impact testing for this material would only apply to Curve A, regardless of a normalization heat treatment. In other words, you cannot take credit for attempting to change the impact test exemptions (moving to Curve B) with heat treatment. Follow the rules for Curve A material in Fig UCS-66 for the thickness limits (0.394" or 10mm).

 

[knstar]

WHERE CAN I FIND THE 0.394 OR 10 MM EXCEPT THE UCS 66 FIG.

in other way,is there any words give a define for the dotted line (x=0.394) which is the end of the lowest tempreture.

 

[metengr]

Review UCS-66 (a) in ASME B&PV Code, Section VIII, Div 1.

 

[knstar]

i have done

but i can't find a word to supply the dotted line(x=0.394) intersect the curve a/b/c/d at the lowest temperature of each curve.

we can find the 0.375 in the ucs 66 table.

but i don't think that the 0.375 is equal the lowest temperature.however i can't find a basis of this code to supply my idea.

 

[metengr]

knstar;
Regarding the answer posted above from an "asme" expert,

For purpose of post weld heat treatment, it is considered that Curve A in UCS 66.1 fits for P-No.1.

. This is not a correct statement and is confusing. I am surprised that an "asme" expert would treat this material as any P-No 1 material. The Code case is quite clear that the reference to P-No 1 material is only for PWHT heat treatment, and Curve A must be used for impact requirements.

 

[knstar]

sorry, your quote is the chinese engineer's question. and the asme expert's answer as below word:


Answer: Yes the provisions given in UCS-66(b) may be used to further reduce the MDMT from Fig. UCS-66. In addition if this material is produced to fine-grain practice and normalized it may be assigned to Curve B.