EN 13445-3 bolts design stress 1

[MichaelDexter]

Hello
Could you help me, how to calculate desgn stress in design temperature for bolts ?
I am praparing calculation for heat exchanger and I must use material A2-70 for bolts, but I don't have it in material library. I calculated design stress for test and 20 deg C condition (based on EN 134445-3: 2009 point 11.4.3.1 and 11.4.3.3) but I can find it for desing condition. I am preparin calculation in VVD ver 10

Thank you
Michael

 

[cardin]

What are the design conditions? In my opinion VVD is not the best program for calculating bolt stresses and a manual calculation i preferred this can be done according to EN13445-3. check also the text after table 11.4.2. hope this helps.

 

[MichaelDexter]

Thanks cardin

I used this text after table for calculating design stress for test condition.
Ftest = 1,5 x f 20degC
f 20degC = Rm/4
I checked values of design stress with sample bolt in VVD. These above two were ok., but f 100deg C and f 200degC were wrong, I don't find how to calculate it

 

[cardin]

I can remember to have read the following values for high temperature loads on these bolt.
100degC use 85% of RM (RM=700N/mm2)
200degC use 80% of RM
300degC use 70% of RM
also: A2 is austenitic and prone to SCC at temp. > 60degC (have to find the Reference again).

 

[MichaelDexter]

Yes I agree, I have found these values in EN 3506-1
Results are acceptable, I checek it with VVD, Thanks

What means this shortcut "SCC" ?

 

[OSIRIS7]

Stress Corrosion Cracking

 

[MichaelDexter]

Thank All for advices
Michael