The bladder accumulator consists of an oil section and a gas section, with the bladder serving as a gas-tight seal. The oil surrounding the bladder communicates with the hydraulic circuit. Consequently, when pressure rises, the gas compresses and draws oil into the bladder accumulator. As pressure decreases, the gas expands, forcing oil back into the system circuit.

Beyond mechanical components, the most critical element of a bladder accumulator is the rubber bladder itself. Fabricated through compression molding, the bladder becomes challenging to control in terms of composition, resistance, integrity, and thickness beyond certain dimensional limits. The most significant issue is that bladder rupture causes the accumulator to cease functioning immediately, leading to complete hydraulic system failure.

【Fault 1】Severe pressure drop requiring frequent air replenishment

The bladder's inflation valve employs a one-way valve design sealed by a conical surface (Figure 1). During operation, vibration may loosen the valve core, causing the sealing cone 1 to fail to close properly and resulting in air leakage. Additionally, grooves on the valve core cone surface or contaminants adhering to the cone surface may also cause air leakage. In such cases, solutions include inserting a 3mm-thick hard rubber gasket 5 into the sealing cap 4 of the inflation valve and regrinding the sealing cone surface to ensure proper sealing.

① Severe air leakage in the air valve, resulting in no nitrogen gas inside the bladder, as well as oil ingress due to bladder damage.

② When the system's maximum operating pressure is too low (below the nitrogen pressure within the accumulator, preventing hydraulic oil from entering the accumulator), the accumulator completely loses its energy storage function (no energy to store).

③ Other valve malfunctions such as leakage. In the system shown in Figure 3, when throttle valve 1 is set too wide or its spool is stuck in the fully open position, a significant portion of the oil released from the accumulator flows back to the tank through the throttle valve. Consequently, the accumulator either fails to function or takes an extended time to replenish the system. This also causes prolonged accumulator charging time. In such cases, reduce the opening of throttle valve 1 and flush the valve.