Accumulator testing

Accumulator performance calculation

Suggested exercises and observations

1. Select menu folder tab 'Accumulators'.

♦ What usable fluid volume is provided by a 20L accumulator into a hydraulic system with a maximum working pressure of 150 bar and minimum working pressure of 100 bar?

♦ Adjust the slidebars or edit the maximum pressure to 210 bar and minimum pressure to 170 bar.

♦ What Accumulator capacity is required to give the same usable fluid volume of 4 litres.

♦ What is the recommended accumulator pre-charge pressure.

Experiment 1: Accumulators are used for a range of different purposes.

Question 1: Describe 3 reasons an accumulator might be used?

High flows for short periods, when pump flow is too small. Dynamic response for fast-acting servo valves. Emergency shut down supply if power fails. Noise attenuation. Temperature or return line pressure stabilisation.

Experiment 2: Accumulators use a gas volume to provide stable pressure energy.

Question 2: Are accumulators sealed for life with one pre-charge pressure?

No. It's likely they will be delivered with only low pressure inside and require recharging after a period of time.

Experiment 3: Accumulators are considered pressure storage vessels and must, therefore, comply with EU's PED, US's ASME legislation.

Question 3: Why are pressure vessels considered so dangerous?

Accumulators store energy that can be dangerous if it is not discharged after the equipment has been turned off. They may also explode if heated by fire.

Accumulator testing

Experiment with hydraulic accumulators

Accumulator performance calculation

Suggested exercises and observations