a pressure gauge for comparing pressures of a gas
- U-tube (auxiliary manometer)
- When using a capacitance manometer
- It shall be measured at the dip-stick hole with an inclined-tube manometer.
- In the case of liquids, the substance itself serves as the fluid in the differential manometer.
- The degassed manometer liquid is put in a bulge provided on the long arm of the isoteniscope.
- After that, the isoteniscope is inclined so that the manometer liquid can flow into the U-tube.
- The sample chamber (figure 3a) is connected to the vacuum line via a valve and a differential manometer (U-tube containing a suitable manometer fluid) which serves as zero indicator.
- Readings of the flow pressure gauge, pressure differential manometer, and the flowing air temperature indicator are to be recorded simultaneously.
- The pressure required for this can be read off the manometer or off an instrument of higher precision.
- The latter consists of a vacuum pump, a buffer volume, a manostat for admitting nitrogen for pressure regulation and manometer.
- A quantity of the liquid, sufficient to fill the bulb and the short leg of the manometer, is put in the isoteniscope.
- The isoteniscope is then placed so that the sample returns to the bulb and fills the short leg of the manometer.
- The pressure in the crankcase shall be measured at an appropriate location. It shall be measured at the dip-stick hole with an inclined-tube manometer.
- Flanges between which the orifice plate is located and clamped are to be provided with pressure take-off lines connected to a manometer.
- Mercury, silicones and phthalates are suitable for use in the differential manometer, depending on the pressure range and the chemical behaviour of the test substance.