Piston Seal Set P21

Piston Seal Set P21 is duoble acting seal for medium duty application and housing according to ISO 7425-1. It is consisting of Polyurethane profile ring and an O-ring as energising element.

Features of this seal are very high static and dynamic sealing effect, high resistance against abrasion and low friction without the apperiance of stick-slip.

Standard cylinders
Machine tools
Injection molding machines
Handling machinery
Industrial vehicles
Agricultural machinery

Standard material
Material Set Code SN211
O-ring NBR 70 ShA, Code N7020
Polyurethane, Code U5012

Pressure, Speed
Working pressure, p in Mpa 25
Running speed, v in m/s 0,5 m/s
Media, Operating temperature
Material Set Code SN211
Hydraulic oils: HL, HLP -30.. +100 ˚C
HFA, HFB fluids +5..+ 50 °C
HFC fluids -30..+40 °C
HFD fluids
Water +5..+50 °C
Mineral greases -30.. +100 ˚C
Max. permissible gap dimension, emax
Working temp. Profil, S Max operating pressure
(°C) (mm) 16MPa 25MPa
60 ≤ 10,5 0,50 0,35
80 ≤ 10,5 0,40 0,25
Surface quality*
Surface roughness Ra Rmax
Sliding surfaces 0.05.. 0,3 μm ≤ 2,5 μm
Groove base ≤ 1,6 μm ≤ 6,3 μm
Groove flanks ≤ 3,0 μm ≤ 15 μm

*Contact area Mr = 50% to 90% at cutting depth c=Rz/2 and reference line Cref=0%