What is pressure defined as? - Answers Force per unit area F=(P)(A)
This pressure gauge has a calibrated dial face with a pointer attached through linkage to a plunger and a
bias spring. This system pressure is connected to the gauge and acts on the plunger.
a. bourdon tube
b. siphon
c. flow meter
d. schrader gauge - Answers d. schrader gauge
What job does a flow control valve perform in a hydraulic system? - Answers Controls the volume of
fluid entering a port of the system to vary the speed
This is used in a hydraulic circuit as petroleum based liquid with 40% water content which acts as oil
a. petroleum based oil
b. invert emulsions
c. glycol
d. vegtetable oils - Answers b. invert emulsion fluids
This is used as a fluid in a hydraulic circuit when there is extreme high and low temperature ranges
a. petroleum based oil
b. invert emulsions
c. glycol
d. synthesized hydrocarbons - Answers d. synthesized hydrocarbons
You would use this valve if a large amount of fluid is to be relieved under a small pressure differential
a. PRV
b. sequencing valve
c. pilot operated relief vavle
d. unloading valve - Answers c. pilot operated relief vavle
, This is a NC valve
What is the purpose of a relief valve in a hydraulic system? - Answers It limits the maximum pressure in
the system
Maintains maximum system pressure
Safety as well for system not over pressurizing
List four (4) purposes that hydraulic fluid serve in a hydraulic system. - Answers a) Power transmission
b) Cooling
c) Sealing
d) Lubrication
Describe cavitations and list four (4) causes of this problem.
1) Inlet not large enough
2) Plugged strainer
3) Viscosity too high
4) Too low operating temps or high operating temperatures
5) Over speed
6) Leaking system lines - Answers Cavitation is caused by restricted flow to the suction side of pump.
When oil is under pressure on discharge side of pump, the air bubbles will implode.