Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
(OP)
Hello my friends!
I would like to know how ring joint are afected in cycling cases and situations where needed isolating results in different flanges temperatures.
Is there a tendency to replace ring joint gaskets with spiral wound gaskets for 2500 class?
Knowing there is loss of preload on the bolts because of plastic deformation on cycling temperature cases, I assume a similar cause affects gaskets and grooves having two flanges at different temperature.
I would like to know how temperatures, loads and deformations affect or not these two types of gaskets in these cases.
Thanks a lot!





RE: Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
RE: Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
RE: Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
Ring-Joint flanges make better engineering sense - the RTJ gasket can deform elasticaly and maintain a seal during temperature cycling. Plus, I've never been a fan of raised-face flanges and flat gaskets ['paper' or spiral-wound] in high-pressure systems. And Class 2500 is pretty much the definition of a high-pressure system.
RE: Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
OK, thanks, so 2500 class would not work fine with spiral wound gaskets ,
I would like to know also if in a lower pressure piping system (for example class 900, 300 and 150), would I have some advantage with spiral wound gaskets? I readed an article wich explained how plastic deformation occurred with ring joint gastkets after a temperature cycling (380ªC, 80bar) creating critical loss of bolt preload. It,s sensible to replace ring joint gaskets where there is lower pressure with spiral wound gaskets ? All this is concerned around the design for a new piping system. it,s not about a replacment on an existing pipe line.
Thanks a lot!!
RE: Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
RE: Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
"Whom the gods would destroy, they first make mad "
RE: Ring joint VS Spiral Wound Gasket class 2500 cycling and different flanges temperatures
From my experience, a RTJ flanged joint will also see unequal expansion of the components (gasket-flange bodies-bolting) when exposed to thermal excursions. The RTJ gasket will be subject it's thermal expansion limits long before the flange begins to absorb sufficient heat to reach an upper equilibrium (thermal expansion is volumetric), and the bolting even more so. Therefore, the gasket will be subjected to additional plastic deformation due to this differential. This may result in leakage, especially after the joint returns to normal conditions.
The SWG will also be compressed more; the windings are small metal components, but they are supported somewhat by the filler materials and tend to 'rebound' better. Most PWR Steam Generators use SWG's throughout the Steam Generator systems.
Dave, most nuc's in the use have been using Bellville style washers in many applications. I don't remember any (it's been 12+ years since I was last in containment) in the primary side, but I'm sure they are there.
Good luck,
Rick