Such gaskets have a stainless steel core, they do not have any filler material and are used non-critical applications as they do not have any compressibility.
Ring Type Joint (RTJ Gasket)
These are usually made of soft steel, as they are moldable and take the shape of the housing, as a result they act as seals.
Except, these are used in highly critical applications where the temperature or pressure is too high for thermoplastic or elastomeric seals. They come in oval or octagonal shapes
They require constant maintenance as they deform, which would jeopardize their purpose.
RTJ Gaskets are being replaced by Spiral Wound Gaskets (SPWG) due to their lower maintenance and longer life.
Kammprofile Gasket (Camprofile Gasket)
Their most common application is heat exchanger. They also get their name “Grooved Metal Gaskets” from their design and profile.
They are typically composed of stainless steels with graphite as a filler material. This design allows for high pressure resistance, as well as rotary pressure due to their graphite filler.
Spiral Wound Gaskets
These come in two variations, one with inner ring and one without.
Spiral Wound with Inner Ring –
These gaskets are now being used as replacements for RTJ and Kammprofile as they have a longer life and are able to withstand high temperature and pressures making them suitable for heat-exchanging applications.
The only downside is that these gaskets are difficult to place in a flange at large diameters, so in this case Kammprofile is suitable.
Spiral Wound Without Inner Ring –
These are similar to the one with an inner ring except that they cannot withstand high pressures above 600 psi, due to no inner rings so they may deform