INSTRUCTION FOR MOUNTING AND USE OF BOURDON TUBE PRESSURE GAUGES
Overpressure allowed on standard pressure gauges.
– Static: 3/4 of pressure gauge value at the end of range.
– Fluctuating: 2/3 of pressure gauge value at the end of range.
– Short time: value of pressure gauge range.
– Warning: overpressure are not admitted over the 10-15% of range.
Do not use the standard pressure gauges with oxygen, corrosive fluids or gas not compatible with copper and its alloys, in this case please contact
Italmanometri Tecnical Service. There are no particular dangers of reaction with other substances under normal operating conditions.
May react with strong oxidizing agents. Nitric acid/sulphuric acid, phosphorus oxide, Peroxide, hydrogen peroxide (H2O2), halogens.
– It is better to change than repair a standard pressure gauge.
– By high quality pressure gauges repair will not be more expensive than purchase a new gauge.
Pressure gauges must be storage observing the following rules:
– Don’t lay more than 3 boxes of pressure gauges.
– Keep away from dust, humidity, high and low temperature.
– Liquid filled pressure gauge must be storage without light.
– Don’t storage liquid filled pressure gauges up side down.
In case of the pressure gauges are between 15/30 degree and storage like the indication written before:
– dry pressure gauges: 6 year – liquid filled pressure gauges: 2 years.
Assembly system of standard pressure gauges
A pressure gauge is calibrated in a vertical position, however and is not a defect, the pointer may be out of zero if the instrument is horizontal, chiefly for low pressure ranges (fig. 1a and 1 b).
Never install the pressure gauge by turning the case but mount it with a wrench by means of the hexagon or flats provided on the sochet (fig. 2)
By BSP parallel standard threads place a gasket between the end of the thread and around the spigot. By BSPT and NPT conical standard thread
thightness is achieved metal on metal without any gasket. However a teflon tape woundaround the thread provides a better tightness and makes the
screwing easier. (fig. 3) Vibrations of the pressure gauges must be avoided to prevent excessive wear of the mechanism. It would be better to set the gauge on a rigid support on wich the vibrations of the pipe have no influence. (fig. 4)
Pressure pulsation: must use liquid filled pressure gauges, fluid separator or coil tube. (fig. 5)