Environmental Engineering Reference
In-Depth Information
Pointer
Bourdon tube
Hairspring
Pinion
Scale
Link
Case
Pressure
Spiral Bourdon
tube (annealed)
Stainless sector gear
Vacuum stop
All stainless-steel movement
Pointer shaft
“S” link
Pulsation dampener plate
Movement
mounting screws
Case attachment
screw hole
Span adjustment
Case seat
“Rolled”, not cut threads
figure 4.41 (Top) Bourdon tube gauge; (bottom) internal components.
4.15.2.4 Plunger Gauge
Most of us are familiar with the simple tire-pressure gauge. This
device is a type of plunger gauge. Figure 4.43 shows a plunger gauge used
in industrial hydraulic systems. The plunger gauge is a spring-loaded
gauge where pressure from the line acts on the bottom of a cylindrical
plunger in the center of the gauge and moves it upward. At full pressure,
the plunger extends above the gauge, indicating the measured pressure.
As the pressure drops, the spring contracts to pull the plunger down-
ward, back into the body (the zero reading indication).
Note:
Spring-loaded gauges are not extremely accurate, but they are
entirely adequate when more precise readings are not necessary.
4.15.3 Temperature gauges
Ensuring that system pressures are properly maintained in equip-
ment and piping systems is critical to safe and proper operation.
Likewise, ensuring that the temperature of fluids in industrial equip-
ment and piping systems is correct is just as critical. Various tempera-
ture-measuring devices are available for measuring the temperature of
fluids in industrial systems.
