Which accumulator type is less bulky and does not discharge at constant pressure?

Which accumulator type is less bulky and does not discharge at constant pressure?

• A. Spring-loaded accumulator
• B. Weight-loaded accumulator
• C. Gas-charged accumulator
• D. Diaphragm accumulator

Answer: (A)

Energy storage in a hydraulic accumulator hinges on how the resisting element applies force to the hydraulic fluid. In a spring-loaded accumulator, the energy is stored in a mechanical spring. The spring force follows Hooke’s law: as the piston moves and the spring is compressed, the resisting force changes, so the hydraulic pressure P = F/A changes during discharge. That means the pressure delivered isn’t constant over the discharge cycle.

Spring-loaded units tend to be more compact because there’s no gas chamber to manage, making them less bulky for a given energy rating. In contrast, devices that use gas, diaphragm, or bladder arrangements rely on a compressible gas or a fixed weight to maintain pressure, which tends to produce a more constant pressure over a larger portion of discharge. Weight-loaded designs, in particular, maintain nearly constant pressure due to the fixed weight.

So the spring-loaded accumulator is the type that is usually smaller and does not discharge at constant pressure.