Pneumatic Systems Flashcards

What is the formula for calculating the theoretical force output of a pneumatic cylinder?

Answer: Force = Pressure × Piston Area

The theoretical output force of a pneumatic cylinder equals the air pressure multiplied by the effective piston area (F = P × A). For the rod side, the rod cross-sectional area is subtracted from the piston area.

What is the purpose of a shuttle valve in a pneumatic circuit?

Answer: To automatically select the higher of two pressure signals and pass it to the output, functioning as a pneumatic OR gate

A shuttle valve has two inlets and one outlet. A free-floating ball or shuttle inside automatically blocks the lower-pressure inlet and connects the higher-pressure inlet to the outlet, functioning as a pneumatic OR logic element.

What is the most common cause of premature pneumatic cylinder seal failure?

Answer: Contaminated or unlubricated air supply, causing seal drying and abrasive wear

The most common cause of premature pneumatic seal failure is contaminated air containing abrasive particles, moisture, or insufficient lubrication. These conditions cause seals to dry out, crack, swell, or wear abrasively, drastically reducing cylinder life.

How does a pneumatic booster (air amplifier) increase pressure?

Answer: By using a large-area piston driven by supply pressure to compress air in a smaller cylinder to a higher pressure

A pneumatic booster uses a large-area piston driven by normal supply pressure on one side to compress air in a smaller-area cylinder on the other side, amplifying pressure by the ratio of the two piston areas. This provides localized high pressure without a high-pressure compressor.

What safety feature must be included when a pneumatic cylinder supports a vertical load?

Answer: A mechanical locking device or holding valve to prevent the load from falling if air pressure is lost

When a pneumatic cylinder supports a vertical load (such as a press or gate), a mechanical lock, pilot-operated check valve, or holding valve must be installed to prevent uncontrolled descent if air pressure is lost or the control valve leaks.

What is the advantage of using polyurethane tubing over nylon tubing in pneumatic systems?

Answer: Greater flexibility, better abrasion resistance, and smaller bend radius

Polyurethane tubing offers greater flexibility, superior abrasion resistance, and tighter bend radius compared to nylon tubing, making it ideal for applications with moving connections, tight routing, and exposure to physical wear.