What kind of indicator mechanism is used to measure oil pressure?

What kind of indicator mechanism is used to measure oil pressure?

• A. A Bourdon tube
• B. A Capsule sensor
• C. A Diaphragm with bellows
• D. A Piezoelectric element

Answer: (A)

The indicator mechanism for measuring oil pressure is a Bourdon tube gauge. A Bourdon tube is a hollow, curved metal tube that tends to straighten when internal pressure increases. That bending motion is transferred through a linkage and gear train to move a needle on the dial, giving a direct, mechanical indication of oil pressure. Capsule sensors, diaphragms with bellows, and piezoelectric elements are used in other types of pressure sensing or electronic transducers, not as the standard mechanical indicator for an oil pressure gauge. Piezoelectric elements produce an electrical signal rather than moving a dial, and the capsule or diaphragm/bellows setups aren’t the typical rugged, simple mechanism used for oil pressure indicators in aircraft.

The indicator mechanism for measuring oil pressure is a Bourdon tube gauge. A Bourdon tube is a hollow, curved metal tube that tends to straighten when internal pressure increases. That bending motion is transferred through a linkage and gear train to move a needle on the dial, giving a direct, mechanical indication of oil pressure.

Capsule sensors, diaphragms with bellows, and piezoelectric elements are used in other types of pressure sensing or electronic transducers, not as the standard mechanical indicator for an oil pressure gauge. Piezoelectric elements produce an electrical signal rather than moving a dial, and the capsule or diaphragm/bellows setups aren’t the typical rugged, simple mechanism used for oil pressure indicators in aircraft.