Cartridge Style Filters for Hydraulic Manifolds

By Ian Duncan

Contamination is the most common reason for failures and subsequent warranty claims for hydraulic manifolds. Even when care is taken to keep a “clean” system, many OEM’s still experience contamination issues. Unfortunately, valves are usually the first component exposed to anything foreign. Filters protecting the entire system, such as those located by the pump or in the reservoir, are not a guarantee for contamination-free clean systems.

The advantages obtained when using cartridge style filters within manifolds include:

• Prolonged cartridge valve life
• Helping valves retain optimum performance characteristics
• Preventive maintenance protection
• Decreased machine downtime

Installed directly into a manifold, these filters can help save valves from outside contamination sources such as cylinders, motors, and quick disconnects. As newer equipment is increasingly efficient, it demands lower leakage valves and tighter tolerances. The lower leakage valves have even less resistance to contamination. This is especially important with both proportional and cartridge valves. Cartridge valves generally contain precision machined parts and require tolerances less than five microns (<5um or .0005”).

Pictured below is a wash down example (B5=1000 filter, manifold mounted approximately 10 feet from main filter):

509 um particle

1673 um particle

Since the cartridge style filter only protects a few valves, they are generally quite small and efficient. The MP Filtri CF series is one variety of cartridge style filters. Additionally, custom filter heads can also be a great way to incorporate high pressure filters with valve controls.