What is the role of the accumulator in the described setup?

• A. It cools the oil to reduce wear.
• B. It filters contaminants.
• C. It acts as a pressure relief.
• D. It stores and releases hydraulic oil to supplement the pump.

Answer: (D)

An accumulator stores hydraulic energy as pressurized oil and releases it to supplement the pump when needed. In this setup, it acts as a small energy reservoir: the oil is kept under pressure by a pre-charged gas (often nitrogen) separated by a bladder or piston. When the pump cannot supply enough flow or pressure to meet a surge in demand, the compressed gas expands and pushes oil into the circuit, boosting flow and helping maintain stable pressure. This smooths out pulsations, reduces pump wear, and improves dynamic response during peak demands or rapid load changes. It’s not primarily meant for cooling, filtering, or acting as a safety relief—those tasks are handled by other components in the system.