Hydraulic accumulators need periodic recertification to ensure they are suitable to continue operating safely. Accumulators are gas cylinders, containing oxygen free nitrogen so are classified as pressure vessels. The recertification process includes intrenal and external inspection and a stretch test to determine the plastic deformation of the body. Tests and inspections are carried out in accordance with the standard BS EN 1968:2002 Transportable gas cylinders – Periodic inspection and testing of seamless steel gas cylinders.
MGR Fluid Power has recently invested in equipment and tooling to inpsect and stretch test both piston and bladder accumulators up to 54 litres in volume. At the moment we have 20 litre piston accumulators in the workshop for recertification, which have been inspected and stretch tested. They have both passed and were refurbished with some new seals and a coat of paint, as good as new.
We can also help with Written Schemes of Examination, which detail the accumulator, its safety system and its inspection and test requirements. The Written Scheme of Examination is a legal requirement and also required by insurers.
In another development MGR Fluid Power has designed and tested and range of accumulator safety blocks for 3/4" to 1 1/2". The blocks are modular and have a short lead time. The picture below shows a bank of 6 off 54 litre accumulators with manaul safety blocks and connecting pipework in a frame. We can supply the complete accumulator system.
Why do we like accumulators?
They are great for storage of hydraulic fluid and can contribute greatly to the efficiency of a hydraulic system. They are very useful for energy saving, when the duty cycle allows it. If there is time in the cycle of the hydraulic system to charge the accumulator then it may be suitbale cost and energy efficient to include them in the design.
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