Operating Conditions 

Pressure Up to 60 MPa
Speed Up to 15 m/s, with reciprocating movements, frequency up to 5 Hz
Temperature -45 °C to +200 °C. Depending on seal and O-Ring material
Media Mineral oil-based hydraulic fluids, flame retardant hydraulic fluids, environmentally friendly hydraulic fluids (bio-oils), phosphate ester, water and others, depending on the seal and O-Ring material compatibility see Materials for PSM
Clearance The maximum permissible radial clearance Smax is shown in Installation Dimensions, as a function of the operating pressure and functional diameter.

Important Note : The above data are maximum values and cannot be used at the same time, e.g. the maximum operating speed depends on material type, pressure, temperature and gap value. Temperature range also depends on media.



Recommended Materials 

The following material combinations have proven effective for hydraulic applications:


PSM in PS8WM

All round material for light to heavy hydraulic applications with linear, short stroke or helical movements in mineral oils, flame retardant hydraulic fluids, phosphate ester, bio-oils or fluids having low lubricating properties:

O-Ring NBR 70 Shore A N
FKM 70 Shore A V
Set Code PS8WMN or PS8WMV


PSM in PS61B

For medium to heavy applications with linear movements in mineral oils and other media with good lubrication:

O-Ring NBR 70 Shore A N
FKM 70 Shore A V
Set Code PS61BN or PS61BV

For specific applications, all PTFE materials are available.

Other material combinations are listed in Materials for PSM.

Materials for PSM 

Installation Dimensions - Standard Recommendations 

Series No. Bore Diameter DN H9 Groove Diameter Groove Width
Standard Application Light Application Heavy Duty Application d1 h9 L1 +0.2
PSM 8 - 16.9 17 - 26.9 - DN - 4.9 2.2
PSM 17 - 26.9 27 - 59.9 - DN - 7.3 3.2
PSM 27 - 59.9 60 - 199.9 17 - 24.9 DN - 10.7 4.2
PSM 60 - 199.9 200 - 255.9 25 - 59.9 DN - 15.1 6.3
PSM 200 - 255.9 256 - 669.9 60 - 199.9 DN - 20.5 8.1
PSM 256 - 669.9 670 - 999.9 200 - 255.9 DN - 24.0 8.1
Series No. Radius Radial Clearance Smax O-Ring Cross Section
r1 max 10 MPa 20 MPa 40 MPa d2
PSM 0.4 0.30 0.20 0.15 1.78
PSM 0.6 0.40 0.25 0.15 2.62
PSM 1.0 0.50 0.30 0.20 3.53
PSM 1.3 0.70 0.40 0.25 5.33
PSM 1.8 0.80 0.60 0.35 7.00
PSM 1.8 0.90 0.70 0.40 7.00

Ordering Guide

PSM complete with O-Ring, standard application:

Series PSM
Bore Diameter DN = 80.0 mm
TMK Part No. PSM0800081

PSM 0800 081 PS8WM N

   1        2      3         4        5

1 TMK Series No.
2 Bore Diameter x 10
3 Groove Width x 10
4 Material Code ( Seal Ring )
5 Material Code ( O-Ring )

Installation Dimensions / TMK Part No.