We consider the weight of Al jacket over thermal insulation & steam tracer piping weight by increasing the insulation thickness, but the stiffness of the tracer pipings are not considered. Just like copper or SS tracers, we consider the CS tracer pipes as flexible enough to ignore. If someone insists to consider the same, can we increase the main piping diameter to provide for the additional moment of inertia, without causing any loss of conservatism in piping stress calculation ?

regards,

sam

P.S.-Which value of wind speed & horizontal accn threshold - 50 or 75 mph, 0.3g or 0.4g should require piping to be analyzed ?

Michael Bussler, Algor, Inc., and Tony Paulin's
'PIPE DESIGN FOR ROBUST SYSTEMS' paper was silent in this regard.

Why has no forum member commented on this topic yet?
Many must have analysed traced piping, have they ignored the weight & stiffness of the tracer altogether ?

regards,
sam

Personally I have never considered this aspect. But this topic has definitely given a food for thought for all of us.

Regards

Dear Anindya,

No explanation, please. My reminder originated from the thinking that steam tracing has become a rare practise nowadays;so in holiday mood many may recollect their past experiences on steam tracers, their leakages etc. It's like the fact -even in the era of email & SMS, we miss the Christmas & New Year cards we were receiving by snail mail earlier.

regards,
sam

Ordinarily I would not think the small diameter tubing would have any significant effect.

However if the tracer was very large and stiff (say a channel or angle welded onto the pipe) it would stiffen it quite a bit.

Having said that I have not had to consider this more than twice in 35 years... this being the second time.

The first time this came up was a request to weld a channel on the bottom of a pipe. The channel was Carbon Steel and the pipe was 304 SS I nixed the whole idea because of differential expansion strains on the bi-metal welds... (which when pressure was added to the loading on the weldment produced some amazingly high numbers)