MDMT Flat head 1

[Makun]

Hi fellows, I'm performing a fitness for service (API 579 Part 3) on a Exchanger who works at low temperature. When I check the design data it has a minimum temperature of -10°C.
The flat head has a thickness of 209mm (SA-105). When I check the minimum temperature trough the toughness curves of ASME VIII, I found that the Minimum temperature is 18°C. I'm useing the curve "B" and the goverment thicknes as 209mm/4
There's some restriction to this kind of component?

Regards

 

[pdiculous963]

Either a stress reduction was used as permitted by UCS-66 or it could have been done wrong. Alternatively, if it was fabricated prior to the introduction of low temperature requirements (1987 Edition of the Code) carbon steels could go down to as low as -20°F prior to requiring impact testing. If it was impact tested I believe you would see that on the Data Report.

 

[Ehzin]

Regarding the UCS-66 statement, see if there's a breakdown of MAWP by component for the exchanger and read into the coincident ratio mentioned in one of the figures of UCS-66.

Thanks,
Ehzin

 

[Makun]

Thanks pdiculous963 and Ehzin, I couldn't found the date of the ASME VIII used in that time