It takes a lot of work to generate gas streams that are uniform and reproducible, with no variation. But if your rotary seal leaks, this can introduce moisture and potential corrosion, and you may see a higher OH peak in measured fibers. Common rotary seal designs, where the shaft slips into a housing and seals on the inside diameter of the rubber O-ring, typically wear quickly. This, of course, impacts the quality of the seal and may force frequent rebuilds to prevent contamination. A better solution is available. The rotary seal by SG Controls seals with the O-ring side against an adjustable glass pressure plate. In this design, there is extremely low wear on the O-ring. This is a reliable rotary seal that works with both types of gas delivery systems. Over the years, I have seen no corrosion issues and minimal leakage issues with this type of rotary seal.


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