Millwright (1).

What are the 2 classes of hydraulics? - CORRECT
ANSWER-Hydrostatic & Hydrodynamic



What causes pressure drop in a hydraulic line? - CORRECT
ANSWER-Excessive Fluid Velocity



What causes aeration in a hydraulic pump? - CORRECT
ANSWER-Air in the suction line



What type of hydraulic cylinder is indicated in the circuit in Figure 1?
- CORRECT ANSWER-Adjustable cushion on extend only



What is Figure 2? - CORRECT ANSWER-Pilot Operated check
valve with a 5:1 line to pilot pressure ratio



What valve is internally piloted from the outlet port and externally
drained? - CORRECT ANSWER-Pressure reducing valve



What valve discharges at a preset pressure? - CORRECT
ANSWER-Pressure Relief Valve



What is the purpose of a pump? - CORRECT ANSWER-Create
Flow

, Which valve limits system pressure when using a fixed
displacement pump? - CORRECT ANSWER-Pressure Relief Valve



What is a symptom of a noisy pump? - CORRECT ANSWER-Low
fluid level in tank



Why can a pressure compensated variable displacement pump
work without a relief? - CORRECT ANSWER-It shifts to minimum
flow



Where is the main purpose pressure relief valve located in a
hydraulic system? - CORRECT ANSWER-Between Pump & control
valve



What instruments are used for testing a hydraulic system? -
CORRECT ANSWER-Tachometer, flowmeter & pressure guage



What are the brownish deposits found on valve spools? -
CORRECT ANSWER-varnish



what is the flare angle for hydraulic tubing that complies with JIC
standards - CORRECT ANSWER-37" included angle