Which component is NOT part of the hydraulic swivel (rotary manifold)?

The priority valve is not considered a component of the hydraulic swivel, also known as the rotary manifold. The primary purpose of the hydraulic swivel is to allow fluid to pass from the stationary parts of the crane to the rotating parts while maintaining a seal and preventing leakage.

The inner spool helps to guide the flow of hydraulic fluid, while the outer casting provides structural integrity and houses the internal components. O-ring seals are crucial for preventing fluid leakage and ensuring that the system remains pressurized. In contrast, the priority valve is typically a separate element within a hydraulic system that prioritizes flow to specific functions or components, making it unrelated to the fundamental construction of the hydraulic swivel itself. Thus, identifying the priority valve as not being a part of the hydraulic swivel is correct.