Which term refers to the pressure at which a hydraulic component fails due to internal stresses caused by pressure?

• A. Operating Pressure
• B. Safe Operating Pressure
• C. Load Pressure
• D. Burst Pressure

Answer: (D)

When a hydraulic component is pressurized, the wall must resist the internal hoop and axial stresses created by the fluid. The pressure at which those stresses exceed the material’s strength and the part ruptures is called burst pressure. This value defines the ultimate failure limit of the component and is typically higher than what you use in normal operation, providing a safety margin.

Understanding why this matters helps: operating pressure is what you expect to use in regular service, and safe operating pressure is a recommended maximum to avoid unsafe conditions; neither is the point where the part fails. Burst pressure is the criterion used to gauge the strength of the component’s walls, depending on wall thickness, diameter, and the material’s tensile strength. If the wall is thicker or the material stronger, the burst pressure goes up. In practice, components are designed to have operating and safe pressures well below their burst pressure, and burst testing is used to verify that margin.