Pressure vessel recertification?

Multihatter

I have a vessel designed, built and certified to ASME Section VIII, Div 1, design rating of 100 psi at a maximum tempeature of 200 F. The new operating conditions for the vessel have changed. It will be operating at a maximum pressure of 30 psi at a maximum temperature of 260 F. Does the vessel need to be recertified based on these new conditions?

CFDFEAGURU

Need some more information:

1. Was the vessel ever in service?
2. Does the vessel contain a lethal substance?
3. If the vessel was in service is it possible to obtain wall thickness measurements of all of the pressure boundaries?
4. Does the material of construction have a different allowable stress at 260 F?

I would bet that you are probably not going to have to recertify the vessel since the pressure is lower as long as you can show compliancy with the ASME code calculations at the lower pressure and higher temperature.

My company designed a boiler to operate at high pressure and then the client lowered the pressure. The only changes we had to make were to the steam drum and superheater safety valves. No recertification was necessary.

Thanks
Matt