New range of filters introduced, new materials enhance filtration

1st December 2017

Drive and control specialist Bosch Rexroth has introduced a new range of hydraulic filter elements that incorporate new materials, which enhance filtration performance for hydraulic systems, while reducing operating costs through increased service life.

The new Pure Power range of elements has been designed using new micro-glass material that, owing to the very small diameter of the fibres, increases interstitial spaces in the same given area to trap and retain 50% more contaminant particles than the range it is replacing. This results in the overall reduced cost of filter elements, their disposal and associated labour, as well as equipment downtime.

“Hydraulic fluid contamination remains the primary cause of system failures, with over 80% of all hydraulic system failures caused by contaminated fluid, therefore, the need to optimise filtration performance is vital,” explains hydraulic solutions provider Hytec Fluid Technologies (HFT) GM Sandor Bottyan.

He adds that to meet the requirements of the ISO 16889:2008 for evaluating filter performance, any filter element must have a beta value exceeding 200, depending on the filter particle size rating. The beta values of the new Pure Power filter material have exceeded 1 000 in real world tests.

“The new Pure Power filter elements draw on new materials technology and Bosch Rexroth’s extensive industry experience to deliver long service life and optimum performance in a broad spectrum of industry applications,” he states.

This improves system availability as hydraulic fluids are cleaned to an optimum condition. It also prevents damage to the system and further contamination by removing a high proportion of the contaminants in the first pass through the filter. This is also the first time that a manufacturer has equipped all elements in its range with an additional antistatic conductive woven filter medium as standard.

He explains that this creates a charge exchange between oil and filter material and reduces the risk of the electrostatic charge and discharge in the filter. End-users of hydraulic systems increasingly use zinc- and ash-free oils, which typically have reduced conductivity. If this is less than 300 picosiemens a metre, the danger of electrostatic discharge increases.

Discharge processes are often visible in the form of lightning discharges or identifiable by a sizzling sound. Each discharge can burn tiny amounts of oil and reduce the service life of the medium. He points out that discharges can also burn holes in the filter layers. This reduces the retention rate and increases the danger of particles passing through the filter and causing damage in the system. The antistatic conductive woven filter medium helps negate the risk of these issues.

Filtration efficiency is even more effective when used with Rexroth filter housings with patented Cycloclean cyclone technology, where a doubling in dirt-holding capacity has been measured according to the ISO 16889 multi-pass test, while retention capability increases tenfold using the same test. This is a direct result of the cyclone design increasing filter capacity by effectively pre-filtering the fluid.

The Bosch Rexroth Pure Power range of filter elements is available in sub- Saharan Africa through specialist hydraulic filtration solutions provider Hytec Fluid Technology, a member of hydraulic, pneumatic and automation solutions provider Hytec Group.