How  to do maintenance on a hydraulic power unit ?

In order to avoid unforeseen production stoppages and thus a considerable drop in the productivity of your industrial site, it is essential to regularly maintain your hydraulic installations. This is valid whatever your field: aeronautics, metallurgy, oil industry, etc… Through this article proposed by AMACH, discover how maintenance on a hydraulic power unit is carried out.

Analysis of oil quality on a hydraulic unit 

The quality of hydraulic oil is an important factor for the proper functioning of the hydraulic system. Indeed, 80% of hydraulic breakdowns are due to poor oil quality, hence the importance of thorough inspection. First of all, checking the oil level, operating temperature, and the absence of leaks can be done internally by an operator. This allows a first inventory of the oil network.

Nevertheless, any other operation on the hydraulic system must be carried out according to precise procedures, which require the use of specific equipment and the intervention of qualified personnel. Thus, the evaluation of the oil quality by hydraulic specialists is divided into three steps:
– Visco-chemical characterization, in other words, the texture of the oil and its adhesive power;
– An analysis of the water content;
– And the determination of the pollution class, linked to the presence of solid microparticles in the oil (note that 90% of hydraulic breakdowns linked to oil quality are due to these particles).

Maintenance: emptying and relacement of used filters.


It is essential to use a filtration unit when adding oil for leveling and when changing oil, so that the new oil is first filtered before being poured into the machine. Likewise, care should be taken when cleaning the inner walls of the tank. Make sure that no impurities (e.g. solid particles) enter the hydraulic system to avoid serious damage, especially on sharp industrial equipment

The filters must also be changed after a certain period of operation. This can be done either by a systematic change or by conditional maintenance.


Checking the other components of the hydraulic system


To ensure proper maintenance on a hydraulic power unit, it is also necessary to check the conditin and operation of the other parts, and to note an anomalies and signs of the wear and tear. These parts are: rotating assemblies, hydraulic pumps and motor, air filters (a point often neglected but which can be the cause of a breakdown), cylinder rod, hoses, couplings, etc…Finally, it is possible to check the condition and efficiency of the rotating pump or motor assemblies, that is to say to check their flow rates, pressures and drain flows. Specific instruments can be installed on the hydraulic unit temporarily to be able to make a continious follow-up to anticipate breakdowns and therefore a better performance.

The proper functionning of a hydraulic power unit depends above all on the quality of the oil. For the complete maintenance or hydraulic repair of your installations to be carried out correctly, it is essential thaht your plant has recourse to professionals.

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