druckueberwachung for fluessigkeitsmanometer

摘要

The manometer system includes a glass tubing having a U-shaped segment therein forming a manometer. One end of the tubing is connected to a vacuum line or a pressure line and the other end of the tubing is vented to atmosphere. The manometer is partially filled with mercury. The first leg of the manometer is in communication with the first end of the tubing and the second leg is in communication with the second end of the tubing with the bight portion therebetween. The second leg has an enlarged diameter portion therein intermediate the bight portion and the upper end of the second leg. The portion of tubing immediately above the enlarged diameter portion is filled with a lightweight fluid and includes a pressure indicating section. The mercury meniscus in the second leg is situated within the enlarged diameter portion so that when there is movement of the mercury meniscus in the enlarged diameter portion, there will be a much larger movement of the lightweight fluid meniscus in the pressure indicating section. A choke is connected to the second end of the tubing to dampen movement of the lightweight fluid meniscus in the pressure indicating section and to inhibit if not prevent rapid escape of mercury should a sudden increase in pressure be applied to the first end of the tubing.