 |
|
Unique Spiral Groove Technology
Patented John Crane spiral grooves are machined into the mating ring
faces. A pressurized suitable inert gas is injected between the
seals. As the shaft rotates, gas flows into the tip of the spiral groove and is compressed at the sealing dam, the ungrooved portion of the mating ring. At the sealing dam, gas is
expanded. The resultant film pressure gives an opening force greater than the closing force, thus separating the
faces.
The Type 2800 spiral groove continues to operate, even if barrier gas pressure is momentarily
lost, maintaining the gas film between the barrier gas and the process |
|
