Thermal Relief Spacing
Thermal Relief Spacing
(OP)
Does anyone know of an existing "rule of thumb" for spacing thermal reliefs in a pipeline (every 1000' etc.) due to solar radiation? I know there are many variables to consider such as pipe size, product contained, elevation changes, where in the world the pipeline is, P&T, etc. I'm not looking rer anything scientific.





RE: Thermal Relief Spacing
RE: Thermal Relief Spacing
Trying to size multiple relief valves in any one blocked-in segment spaced a certain distance apart has the potential to complicate the problem considerably, as it becomes a problem with possible multiple flow paths being set up within the same pipe, even if you don't consider elevation differences between relief points, or a nonuniformtemperature distribution along the pipe segment.
What would you be doing, if you knew that you could not fail?
RE: Thermal Relief Spacing
RE: Thermal Relief Spacing
For liquid that could not vaporize given the conditions and would not flash when relieved, we considered 250 liters as the maximum blocked-in liquid volume in pipes exposed to sunlight before installing a thermal relief valve
We had a liquid expansion coefficient limit to exclude some liquids from that, but I can't find it right now.
RE: Thermal Relief Spacing
What would you be doing, if you knew that you could not fail?