Low Pressure Duplex Filter Pi 281

Filtration Group


Related Documents:
Spec/Diagram PDF

Item Information:

High performance filters for modern hydraulic systems.  Nominal pressure 10/16 bar (140/230 psi), nominal size 1250 up to 8000.

  • Modular system
  • Compact design
  • Minimal pressure drop through optimal flow design
  • Visual/electrical/electronic maintenance indicator
  • Flanged connections
  • Quality filters, easy to service
  • Equipped with highly efficient glass fibre Sm-x filter elements
  • Beta rated elements according to ISO 16889 multipass test
  • Elements with high differential pressure stability and dirt holding capacity
  • Worldwide distribution

Flow rate/pressure drop curve complete filter

y = differential pressure Δp [bar]
x = flow rate V [l/min]
1 = Sm-x 3 3 = Sm-x 10 5 = Mic 10 7 = Drg 40 9 = Drg 100
2 = Sm-x 6 4 = Sm-x 25 6 = Drg 25 8 = Drg 60  
3. Separation grade characteristics 4. Filter performance data

x=particle size [µm]

determined by multipass tests (ISO 16889)
calibration according to ISO 11171 (NIST)

tested according to ISO 16889 (multipass test)


Sm-x elements with
max. Δp 10 bar
Sm-x    3     ß5(c)    ≥200
Sm-x    6     ß7(c)    ≥200
Sm-x    10   ß10(c)   ≥200
Sm-x    25   ß20(c)   ≥200
Values guaranteed up to
5 bar differential pressure
5. Quality assurance
Filtration Group filters and filter elements are produced according to the following international standards:
6. Symbols
7. Order numbers
8. Technical specifications
Design: line mounting filter, mounting via through holes at supporting stands
Fitting position: upright
Butterfly valve switch over device  
Temperature range: - 10 °C to + 100 °C (other temperature ranges on request)
Filter housing material: steel welded construction
Material of seals: NBR (other materials on request)
NBR (other materials on request) Δp 3.5 bar +/- 10 %
Activating pressure of optical/electrical Δp 2.2 bar +/-10 %
contamination indicator:  
Electrical data of contamination indicator:  
Maximum voltage: 250 V AC/200 V DC
Maximum current on contact: 1 A
Maximum contact load: 70 W
Type of protection: IP 65 when inserted and secured
Contact: bistable
Cable sleave: M20x1.5

The switching function can be changed by turning the electric upper part by 180° (normally closed contact or normally open contact). The state on delivery is a normally closed contact. By inductivity in the direct current circuit the use of suitable protection circuit should be considered. Further maintenance indicator details and designs are available in the maintenance indicator data sheet.

We recommend you to contact us concerning applications of our filters in areas governed by the EU Directive 94/9 EC (ATEX 95). The standard version can be used for liquids based on mineral oil (corresponding to the fluids in Group 2 of Directive 97/23 EC Article 9). If you consider to use other fluids please contact us for additional support.

* Subject to technical alteration without prior notice.

9. Dimensions