Hello all!!

I have been reading the Technical Reference Manual 6.19 about suStained stresses and it is really interesting. It surprises to me that removing supports THAT lift-off during operation (as I usually do) when calculating the sustained stresses is not neither clear nor evident and some people think is necessary and others not (as CAESAR responsibles).
CAESAR technical reference 6.20 says that "if the pipe became overstressed, it would yield and sag back to the support". Do you think it would be so in the case of lifting, i.e, 140 mm??
I have read somewhere that a lift of up to 1/4" may be considered as negligible but when it is bigger I am not sure if it could suppose a problem...
I would like to know the opinion of other people, about negligible lift-off, if they remove the supports with any lift or only if they exceed certain limit,etc..

By the way, why B31.1 doesn't state it clearly and there would not be any doubt for anybody??!!

Best regards