Tek-Tips is the largest IT community on the Internet today!
Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!
-
Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!
BS PD:5500 vs. ASME Sec VIII Div 1 3
- Thread starter zjliang
- Start date
-
2
- #2
- Thread starter
- #3
It has been a number of years since I worked with BS-5500, but best recall is that it was more like ASME VIII Division 2 than Division 1.
Steve Braune
Tank Industry Consultants
Steve Braune
Tank Industry Consultants
- Thread starter
- #5
zjliang,
I guess I was thinking more along the lines of allowable stresses and design results. BS-5500 had much higher allowable stress values than Div 1... much more like Div 2. But those observartions are from many years ago. Sorry to have gotten you off track on this.
Steve Braune
Tank Industry Consultants
I guess I was thinking more along the lines of allowable stresses and design results. BS-5500 had much higher allowable stress values than Div 1... much more like Div 2. But those observartions are from many years ago. Sorry to have gotten you off track on this.
Steve Braune
Tank Industry Consultants
zjliang,
PD5500 is essentially EN 13445. As Steve pointed out it is similar to Div.2
To give the quick answer to your question the general differences between PD 5500 and Div 1 and similar to the differences between Div. 1 and Div. 2.
In some cases, PD 5500 allows higher stresses than Div. 2. Duplex stainless is a good example of this. For example, 2205 can have an allowable tensile stress of greater than 31000 psi at 175C. Vaccum is handled differently than ASME.
PD5500 has tighter tolerances than ASME. For example, maximum out-of-roundness for external pressure is 0,5% but it is not measured based on Dmax - Dmin. Vessels exceeding this can be analyzed to see if they are acceptale. However, if the peaking values in PD5500 are exceeded additional engineering is not permitted to make the vessel acceptable. I've just been through a case with a large (10 m diameter) pressure vessel where both of these issues had to be addressed.
PD5500 also has more fabication tolerances than the ASME codes. maximum deviations of nozzles from tangent lines are specified.
There can be greater NDT requirements.
I know this is slightly off what you are looking for but differences in design rules and allowables also have a price which often is not seen.
I hope this helps.
PD5500 is essentially EN 13445. As Steve pointed out it is similar to Div.2
To give the quick answer to your question the general differences between PD 5500 and Div 1 and similar to the differences between Div. 1 and Div. 2.
In some cases, PD 5500 allows higher stresses than Div. 2. Duplex stainless is a good example of this. For example, 2205 can have an allowable tensile stress of greater than 31000 psi at 175C. Vaccum is handled differently than ASME.
PD5500 has tighter tolerances than ASME. For example, maximum out-of-roundness for external pressure is 0,5% but it is not measured based on Dmax - Dmin. Vessels exceeding this can be analyzed to see if they are acceptale. However, if the peaking values in PD5500 are exceeded additional engineering is not permitted to make the vessel acceptable. I've just been through a case with a large (10 m diameter) pressure vessel where both of these issues had to be addressed.
PD5500 also has more fabication tolerances than the ASME codes. maximum deviations of nozzles from tangent lines are specified.
There can be greater NDT requirements.
I know this is slightly off what you are looking for but differences in design rules and allowables also have a price which often is not seen.
I hope this helps.
- Status
Similar threads
- Question
- Locked
- Question