EuroWeld
Mechanical
- Nov 7, 2011
- 50
Hello all,
Recently we booked an order for fabricating a super duplex heat exchanger.
Design code ASME VIII div 1 including U-stamp.
During the procurement stage we are facing some difficulties buying the correct S32750-F53 seamless tubes.
The only option we have at this moment is an alternative in grade S32760-F55.
We searched the whole european (customer requirement) without any success.
We noticed that the ASME VIII div 1 does not include this super duplex grade S32760. Bacause of this reason it is not allowed for use in U-stamped designs.
Can somebody inform me why this grade S32760 is not included in the ASME VIII div 1? Seamless tubes are according to SA-789.
Both grades are included in ASME II Part A. Is this strange or unusual?
This alternative grade has a slighty lower tensile strenght and the chemical composition is somewhat different.
Looks like minor differences between apparently almost similar materials. After doing some investigation on the internet I have notices some preferences in different service conditions. All additional testing that we specify can be achieved by the tube supplier.
Our client is willing to accept this alternative grade but how about the code?
Are there some other manners to get this material accepted by the code? Does somebody have other suggestions that will help?
Thanks in advance,
Euroweld
Recently we booked an order for fabricating a super duplex heat exchanger.
Design code ASME VIII div 1 including U-stamp.
During the procurement stage we are facing some difficulties buying the correct S32750-F53 seamless tubes.
The only option we have at this moment is an alternative in grade S32760-F55.
We searched the whole european (customer requirement) without any success.
We noticed that the ASME VIII div 1 does not include this super duplex grade S32760. Bacause of this reason it is not allowed for use in U-stamped designs.
Can somebody inform me why this grade S32760 is not included in the ASME VIII div 1? Seamless tubes are according to SA-789.
Both grades are included in ASME II Part A. Is this strange or unusual?
This alternative grade has a slighty lower tensile strenght and the chemical composition is somewhat different.
Looks like minor differences between apparently almost similar materials. After doing some investigation on the internet I have notices some preferences in different service conditions. All additional testing that we specify can be achieved by the tube supplier.
Our client is willing to accept this alternative grade but how about the code?
Are there some other manners to get this material accepted by the code? Does somebody have other suggestions that will help?
Thanks in advance,
Euroweld