Spiral wound gaskets are semi-metallic products designed
for high pressure and temperature applications and where
vibration or flow rates are beyond the capability of
conventional gasket materials. They have the ability to
recover under the action of fluctuating loads caused by
process fluid pressure and temperature changes, flange
rotation, bolt stress relaxation and creep.
The gasket sealing element consists of a pre-formed ‘V’ metallic winding strip with layers of a softer, more compressible material which, during compression, is densified and flows to fill imperfections in the flange surface when the gasket is seated. The metal strip holds the filler, giving the gasket mechanical resistance and resilience.
Spiral wound gaskets can be manufactured from various
filler materials and assuming an appropriately rated metal
winding strip is selected, the operating limits of
available sealing materials are:
Sealing Layer Material | Minimum Temperature | Maximum Temperature | Maximum Pressure | Gas Tightness | Application |
Graphite | -200°C | 450°C | 400 bar | Good | Aggressive Media |
PTFE | -200°C | 260°C | 100 bar | Good | Aggressive Media |
High Temp | -200°C | 1000°C | 5 bar | Average | Gases |
High Temp + Graphite | -200°C | 800°C | 100 bar | Good | Gases |
(If you are on a mobile device and cannot see the entire table, scroll the table left/right.)
Pipeline gaskets are appropriately identified with pressure
rating and size/specification of flanges.
When correctly sized and fitted to compatible flanges, non-standard gaskets will seal pressures up to 400 bar, although higher pressures can be considered.
Spiral wound gaskets are available in a wide range of metals/alloys; the majority, in one of the following configurations:
Whilst standard pipeline gaskets are available with a 4.5mm thick sealing element and 3.0mm thick inner and/or outer rings, other available sealing element thicknesses with guide diameters and recommended compression thicknesses are:
Sealing Element Thickness | Minimum Diameter | Maximum Diameter | Compressed Thickness |
Graphite | -200°C | 450°C | 400 bar |
PTFE | -200°C | 260°C | 100 bar |
High Temp | -200°C | 1000°C | 5 bar |
High Temp + Graphite | -200°C | 800°C | 100 bar |
(If you are on a mobile device and cannot see the entire table, scroll the table left/right.)