Which of the following is one of the primary mechanical pressure measuring instruments found aboard ships?

The Bourdon tube is a primary mechanical pressure measuring instrument commonly found aboard ships due to its reliability and accuracy in measuring pressure changes. This instrument operates through a curved tube that straightens when pressure is applied, causing a pointer to move over a dial to indicate the pressure level. The simplicity of its mechanical design allows it to function effectively in the maritime environment, where it is often subject to vibrations, temperature fluctuations, and corrosive conditions.

Additionally, the Bourdon tube is recognized for its resilience and maintenance-free operation, making it ideal for long-term use in various applications, including fuel oil systems, cooling water circuits, and hydraulic systems aboard ships. Its ability to provide immediate readings without the need for external power sources further emphasizes its practical utility in the field.

While other instruments like piezoelectric sensors, hydraulic gauges, and digital manometers serve important roles in pressure measurement, they may not be as universally used on ships or might require more complex arrangements for installation and operation. Therefore, the Bourdon tube stands out as a foundational technology in mechanical pressure measurement utilized in marine applications.