EN 13445 allowable bolt stress
EN 13445 allowable bolt stress
(OP)
Suppose one has to calculate with A2-70, or more specific with 1.4404 +C700 acc. EN 10269.
For the allowable bolt stress the EN 13445-3 §6.1.1 clearly excludes bolts, and refers to clause 11 and 12 of EN 13445-3.
In §11.4.3.1 for austenitic material it states fB = Rm,t/4. This means tensile strength at designtemperature. Now where do I find this? Not in EN 10269 (yes, for 1.4404 +AT it does, but that is the A2-50 equivalent). I have checked EN ISO 3506-1, AD Merkblatt W7, DIN 267-13.
It also appears that this tensile strength does not remain the same, otherwise the tensile strength of 1.4404 +AT and +C700 should be the same.
Is there anyone who has experience on how to cope with this? A2-70 is a widely used material, and I can not believe it is impossible to use it with regard to EN 13445.
Is it allowed to extrapolate the tensile strength? For example: at 200ºC => Rm,t = 390 * (700/500) = 546 N/mm² ?
Kind regards,
Kelly
For the allowable bolt stress the EN 13445-3 §6.1.1 clearly excludes bolts, and refers to clause 11 and 12 of EN 13445-3.
In §11.4.3.1 for austenitic material it states fB = Rm,t/4. This means tensile strength at designtemperature. Now where do I find this? Not in EN 10269 (yes, for 1.4404 +AT it does, but that is the A2-50 equivalent). I have checked EN ISO 3506-1, AD Merkblatt W7, DIN 267-13.
It also appears that this tensile strength does not remain the same, otherwise the tensile strength of 1.4404 +AT and +C700 should be the same.
Is there anyone who has experience on how to cope with this? A2-70 is a widely used material, and I can not believe it is impossible to use it with regard to EN 13445.
Is it allowed to extrapolate the tensile strength? For example: at 200ºC => Rm,t = 390 * (700/500) = 546 N/mm² ?
Kind regards,
Kelly





RE: EN 13445 allowable bolt stress
When it comes to pressure codes, EN is by far a mature code to be seriously considered, at times.
RE: EN 13445 allowable bolt stress
200 C --> 81% of 25C Rm
300 C --> 77%
400 C --> 74%
RE: EN 13445 allowable bolt stress
RE: EN 13445 allowable bolt stress
Since this thread did not receive many replies, I suggest that you submit a new thread to the forum Metal and Metallurgy engineering. There will be other experts that frequently contribute there (Metengr is one) that are very familiar with pressure vessel codes. It may be ASME instead of EN, but they will likely provide additional information related to strain hardened stainless steel fasteners (ASTM A193 Grade B8 Class 2).