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| Typical Number in Hospital: 300 | Cost Bands: 1 | References: 2 |
This is an elaboration of the aneroid manometer used for higher pressures (up to 2000 psi). The corrugated cylinder of the aneroid manometer is replaced by a curved or spiral flattened tube which attempts to straighten when pressure is applied to the inside of it. The free end of the tube is connected to a rack and pinion to which a pointer is attached. These types of gauge are found on gas cylinders to indicate the pressure of the contents (and by inference the fullness). They are also found on anaesthetic apparatus to show the pressure of the pipelines (4 bar, 60 psi in UK). Where they are used on cylinders which contain liquids (e.g. compressed carbon dioxide, nitrous oxide, cyclopropane) the pressure is not a good guide to the fullness since pressure only falls significantly when all the liquid has been evaporated.
Content and Design Copyright 2000 Dr. Malcolm C Brown. See Title Page for more details