What does it mean to "bleed" a hydraulic line?

To "bleed" a hydraulic line specifically refers to the process of releasing trapped air within the hydraulic system. Air within hydraulic lines can lead to inefficiencies and malfunctions, as hydraulic systems rely on incompressible fluids to transmit force effectively. When air is trapped in the system, it can compress, resulting in a spongy response and poor control of hydraulic components.

Bleeding the lines eliminates this air, ensuring that the hydraulic fluid can flow freely and the system operates as intended. This process typically involves opening a bleed valve and allowing fluid to escape until a steady stream is achieved, indicating that all air has been expelled. By ensuring the hydraulic line is free of air, the system's performance and reliability are maximized, ultimately improving the safety and efficiency of the machinery involved.