209.07-209.09 Flashcards
How do you Measure ΔP across a pneumatic component
you typically use a device called a differential pressure gauge. This gauge measures the pressure at two points and calculates the difference between them. Here’s a simple way to understand it:
Connect the gauge: Attach the gauge to the two points where you want to measure the pressure difference.
Read the gauge: The gauge will display the difference in pressure between these two points
Identify factors that affect pneumatic actuator speed and force
Supply Pressure: Higher supply pressure can increase both speed and force.
Load: The weight or resistance the actuator has to move affects its speed and force. Heavier loads slow it down.
Cylinder Size: Larger cylinders can exert more force but may move slower due to increased air volume.
Air Flow Rate: The rate at which air is supplied affects speed. Faster air flow can increase speed.
Friction: Internal friction within the actuator can reduce speed and force.
Temperature: Changes in temperature can affect air density and pressure, impacting performance
Describe types of resistance in a pneumatic system
Frictional Resistance: This occurs between moving parts, like pistons and cylinders, and can slow down the movement.
Flow Resistance: Caused by the air moving through pipes and valves, which can create pressure drops.
Load Resistance: The resistance from the load that the pneumatic system is trying to move or lift
Calculate net force output of a cylinder
Net Force
To calculate the net force output of a pneumatic cylinder, you can use the formula:
(
Pressure
×
Area
)
−
Frictional Force
Net Force=(Pressure×Area)−Frictional Force
Pressure is the air pressure supplied to the cylinder (in Pascals or psi).
Area is the cross-sectional area of the piston (in square meters or square inches).
Frictional Force is the force due to friction that opposes the movement.
Explain Pascal’s law significance in fluid power
It allows hydraulic and pneumatic systems to transmit force efficiently.
It enables the multiplication of force, which is why small input forces can be used to lift heavy loads in hydraulic systems
State Pascal’s law
Pascal’s Law states that when pressure is applied to a confined fluid, the pressure change occurs throughout the entire fluid equally.
How do you read a rotameter
Look at the float inside the tube.
The flow rate is read at the center of the float, where it aligns with the scale on the tube
How do you Connect a rotameter
Ensure the rotameter is installed vertically.
Connect the inlet and outlet to the flow line, following the direction of flow indicated by an arrow on the rotameter.
Rotameter
used to measure the flow rate of liquids or gases.
How do you Connect a pneumatic pressure gauge
Attach the gauge to the pressure source using the appropriate fittings.
Ensure all connections are secure to prevent leaks.
How do you read a pneumatic pressure gauge
Observe the needle on the dial.
The needle points to the pressure value on the scale, usually measured in psi (pounds per square inch) or bar.
Pneumatic pressure gauge
measures the pressure of gases.
How do you Read an air temperature gage
Check the display or dial.
The temperature is shown in degrees Celsius (°C) or Fahrenheit (°F).
Air Temperature Gauge
measures the temperature of the air
SI Units
The SI unit for measuring flow rate is cubic meters per second (
m
3
/
s
m
3
/s).
For smaller flow rates, liters per second (
L
/
s
L/s) or liters per minute (
L
/
m
i
n
L/min) are often used
US Customary Units
In the US Customary system, flow rates are often measured in cubic feet per minute (CFM).
Gallons per minute (GPM) is also a common unit, especially for liquids
Operation of a Rotameter
Design: It consists of a tapered tube, usually made of glass or plastic, and a float inside that tube.
Flow Measurement: As fluid flows through the tube, it causes the float to rise. The position of the float is an indication of the flow rate.
Tapered Tube: The tube is wider at the top than at the bottom. This design allows the float to rise to a position where the upward force from the fluid flow equals the downward gravitational force on the float.
Reading the Flow Rate: The flow rate is read from a scale on the tube, which corresponds to the position of the float.
Explain the effect of air temperature in pneumatics
Pressure Changes: As air temperature increases, the air molecules move faster and spread out, which can increase the pressure in a pneumatic system. Conversely, if the temperature decreases, the air molecules slow down and come closer together, reducing the pressure.
Volume Changes: According to the ideal gas law, if the temperature of the air increases while the pressure is constant, the volume of the air will also increase. This can affect the performance of pneumatic devices that rely on specific volumes of air.
Efficiency: Higher temperatures can lead to increased energy losses due to heat, which can make pneumatic systems less efficient. Cooler temperatures might improve efficiency but can also cause issues like condensation.
Material Expansion: Components in a pneumatic system can expand or contract with temperature changes, potentially affecting seals and connections.
Describe the operation of an air lubricator
device used in pneumatic systems to add a controlled amount of oil into the compressed air. This helps to lubricate the moving parts of pneumatic tools and machinery, reducing friction and wear. Here’s how it operates:
Air Flow: Compressed air enters the lubricator.
Oil Reservoir: The lubricator has a reservoir filled with oil.
Venturi Effect: As the air passes through a narrow section, it creates a low-pressure area (Venturi effect).
Oil Mist: The low pressure draws oil from the reservoir, creating a fine mist.
Mixing: The oil mist mixes with the air.
Lubrication: The air-oil mixture travels through the system, lubricating components.
Describe the operation of a pneumatic filter
is used to remove contaminants like dust, dirt, and moisture from compressed air. This ensures that the air is clean before it reaches the pneumatic equipment. Here’s how it operates:
Air Entry: Compressed air enters the filter.
Filtration Element: The air passes through a filter element, which traps solid particles.
Moisture Removal: Some filters have a mechanism to remove moisture, often using a coalescing process where water droplets combine and fall to the bottom.
Clean Air Output: The cleaned air exits the filter, ready for use in the system.
How do you Drain a pneumatic filter
Safety First: Ensure the system is depressurized before starting.
Locate the Drain Valve: Most filters have a drain valve at the bottom.
Open the Valve: Carefully open the valve to let out any accumulated water or contaminants.
Close the Valve: Once drained, close the valve securely
How do you Inspect and refill an air lubricator
Depressurize the System: Always ensure the system is off and depressurized.
Check the Lubricator: Look for any signs of wear or damage.
Refill: If needed, refill with the appropriate oil as specified by the manufacturer.
How do you Adjust air lubricator rate
Locate the Adjustment Screw: This is usually on top of the lubricator.
Turn the Screw: Adjust the screw to increase or decrease the oil flow rate. Follow the manufacturer’s guidelines for the correct rate.
How do you Inspect and replace an air filter element
Depressurize the System: Ensure the system is safe to work on.
Remove the Filter Housing: Carefully open the housing to access the filter element.
Inspect the Element: Check for dirt or damage.
Replace if Necessary: If the element is dirty or damaged, replace it with a new one.
