Single-Acting Mechanical Seal

Available screw drive seal designs include posurve lip seals, single acting mechanical, or double acting mechanical. All seals dry running. 

Single-acting mechanical seals are still most frequently used for this task. The functional principle means that there is no 100% leak-tight mechanical seal, as the rotating sliding surface is lubricated and carried by the process medium. This... 

Figure 3.25 Section through a vacuum pump with single-acting mechanical seal.

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