John_Ioannou
Mechanical
- Oct 26, 2019
- 1
Hi,
I am currently reviewing some designs of rectangular test blanks that are used to blank openings in a large pressure vessel in order to carry out a pressure and leak test.
The blanks and apertures are rectangular and they have been designed using the stress classification method in 13445. The plate is dominated by membrane + bending stress, but there are no peak or localised stresses as the geometry is uniform ie. it’s just a flat plate that’s subject to bending. Under these circumstances would it be appropriate to multiply the maximum allowable stress by 1.5 as allowed by the code for membrane + bending? I would assume for there to be a sufficient safety factor it would be ALARP to constrain the maximum allowable stress as per the DBF method.
I am not particularly experienced in DBA principals but any help on this would be very much appreciated.
I am currently reviewing some designs of rectangular test blanks that are used to blank openings in a large pressure vessel in order to carry out a pressure and leak test.
The blanks and apertures are rectangular and they have been designed using the stress classification method in 13445. The plate is dominated by membrane + bending stress, but there are no peak or localised stresses as the geometry is uniform ie. it’s just a flat plate that’s subject to bending. Under these circumstances would it be appropriate to multiply the maximum allowable stress by 1.5 as allowed by the code for membrane + bending? I would assume for there to be a sufficient safety factor it would be ALARP to constrain the maximum allowable stress as per the DBF method.
I am not particularly experienced in DBA principals but any help on this would be very much appreciated.