OECP Hydraulic Systems & Pneumatics 3

Question 1

What is the primary advantage of pneumatic systems over hydraulic systems for many construction site applications?

Accepted Answer

Pneumatic systems are cleaner and simpler because exhaust air vents harmlessly to atmosphere

Answer

Pneumatic systems generate significantly higher forces per cylinder bore size

Answer

Pneumatic systems operate at much higher pressures than hydraulic systems

Answer

Pneumatic systems provide more precise speed control of actuated tools

Question 2

What is the typical operating pressure range for industrial pneumatic systems and pneumatic tools used in construction?

Accepted Answer

80–150 PSI

Answer

1–10 PSI

Answer

500–1,000 PSI

Answer

2,000–3,000 PSI

Question 3

What is the purpose of an FRL (Filter-Regulator-Lubricator) unit installed in a pneumatic supply line?

Accepted Answer

To condition compressed air by removing contaminants, setting pressure, and adding lubrication

Answer

To boost air pressure above compressor output for high-demand tools

Answer

To measure and record compressed air volume consumption over a shift

Answer

To convert pneumatic pressure signals into electrical control signals

Question 4

What is the primary hazard when using compressed air tools and equipment on a construction site?

Accepted Answer

High-velocity air injection injuries and projectile particles striking workers

Answer

Electrical shock from static charge buildup inside pressurized air lines

Answer

Chemical burns from acidic moisture that accumulates in compressed air lines

Answer

Low-frequency vibration damage from standing waves in long pneumatic hose runs

Question 5

What causes moisture buildup inside compressed air lines and pneumatic tools during normal operation?

Accepted Answer

Water vapor present in atmospheric air that condenses as compressed air cools in the lines

Answer

Compressors that are undersized for the application and run continuously at maximum load

Answer

Inadequate lubrication of compressor piston rings allowing coolant to enter the air stream

Answer

Air inlet filters that are too restrictive, causing condensation on the pressure side

Question 6

What is the correct procedure for safely disconnecting a pneumatic tool or hose from an air supply line?

Accepted Answer

Shut off the air supply valve, bleed residual line pressure, then disconnect the fitting

Answer

Pull the quick-connect fitting sharply outward while the tool trigger is held open

Answer

Disconnect the fitting rapidly while directing the open end away from all personnel

Answer

Release the tool trigger, then pull the quick-connect without bleeding line pressure first

Question 7

What does dew point indicate when evaluating the quality of compressed air in a pneumatic system?

Accepted Answer

The temperature at which water vapor in the compressed air will condense into liquid

Answer

The maximum rated working pressure of downstream pneumatic components

Answer

The volume of free air delivered per minute at rated compressor pressure

Answer

The minimum safe ambient temperature for operating pneumatic tools outdoors