Contamination and flushing of hydraulic systems

The service life of a hydraulic system depends largely on the quality of the oil, but the presence of contaminants in the total system is also a crucial factor. Therefore, it is very important that pipeline systems are flushed before being brought into service. System contamination is measured in the ISO-4406, or the NAS class. Both state information about the size and quantity of contaminants and metal particles in the oil. According to both standards, the lower the quantity of particles, the cleaner the oil. New systems with modern proportional and servo valves must have a minimum NAS class of 7-8 (ISO 18/16/13).

In most cases, the entire system will need to be flushed after you have undertaken major modifications or identified damage to the pumps, motors and/or cylinders. Flushing ensures the necessary level of cleanliness, and also helps to prevent new damage.
WK Hydraulics possesses flushing and monitoring equipment, which puts it in a perfect position to help you to achieve the necessary level of cleanliness in your system. Needless to say, any active system will suffer a certain degree of normal wear and tear, but the age, load and ageing level of the oil will have an effect. Usually, wear particles are filtered by the return-, or pressure line filters, which makes regular inspection of the filter elements very important. These may be replaced as necessary.