Merkel U-Ring Seal Set 02170 pages
Hydraulic Seals | Piston Seals | Merkel U-Ring Seal Set 0217
Merkel U-Ring Seal Set 0217
Operating conditions
Fabric
Pressure p Hydraulic
Back-up ring
25 or 40* MPa
* max. pressure depends on the profile.
NBR U-ring
Pressure p Pneumatic
5 MPa
Running speed v
1,5 m/s
Medium/
Temperature
80 NBR B246/BI-NBR
B4 B248/PA 6.G200
80 NBR B246/BI-NBR
B4 B248/POM PO202
Hydraulic oils HL, HLP
–30 °C … +100 °C
–30 °C … +100 °C
Product description
HFA fluids
+5 °C … +60 °C
+5 °C … +60 °C
Two-piece Merkel seal set comprising an elastomer U-ring with
an elastomer sealing edge, a fabric reinforcement on the contact
area and an active back-up ring.
HFB fluids
+5 °C … +60 °C
+5 °C … +60 °C
HFC fluids
–30 °C … +60 °C
–30 °C … +60 °C
HFD fluids
–
–
Water
+5 °C … +100 °C
+5 °C … +100 °C
HETG (rapeseed oil)
Single-acting piston seal for use in hydraulics or pneumatics
■■
■■
–30 °C … +80 °C
–30 °C … +80 °C
–30 °C … +80 °C
HEPG (glycol)
Product advantages
■■
–30 °C … +80 °C
HEES (synthetic ester)
–30 °C … +60 °C
–30 °C … +60 °C
Mineral greases
–30 °C … +100 °C
–30 °C … +100 °C
Design notes
Low friction due to fabric reinforcement
Large range of dimensions
Activated back-up ring prevents extrusion
Please observe our general design notes in ➔ Technical Manual.
Surface quality
Peak-to-valley heights
■■
Rmax
0,05 … 0,3 µm
≤2,5 µm
Groove base
≤1,6 µm
≤6,3 µm
Groove flanks
Pneumatic applications
Ra
Sliding surface
Application
≤3,0 µm
≤15,0 µm
Percentage contact area Mr >50% to max. 90% at cutting depth c = Rz/2 and reference line
C ref = 0%.
Material
U-Ring
Admissible gap dimension
Material
Code
NBR U-ring
80 NBR B246
Cotton fabric
BI-NBR B4 B248
Code
Polyacetal POM
POM PO202
Back-up ring
>300 mm
32 MPa
40 MPa
0,60 mm
0,40 mm
3,5 … 4,0
1,20 mm
1,00 mm
1,00 mm
0,50 mm
1,80 mm
1,40 mm
0,90 mm
0,70 mm
2,00 mm
1,60 mm
1,10 mm
0,90 mm
The largest gap dimension occurring on the non-pressurised side
of the seal in operation is of vital importance for the function of
the seal. ➔ Technical Manual.
Tolerances
Material
Code
Polyamide
PA 6.G200
Other materials like PTFE bronze back-up ring on enquiry.
26 MPa
0,70 mm
8,0
Material
16 MPa
0,80 mm
5,0 … 6,0
Back-up ring
<300 mm
BR
2,5 … 3,0
The admissible gap width, tolerances, guide play and deflection of the guide under load are to be taken into account when
designing d2. ➔ Technical Manual.
Nominal Ø D
D
d
≤1120 mm
H8
h10
Fitting & installation
Careful fitting is a prerequisite for the correct function of the seal.
➔ Technical Manual.
© Freudenberg Sealing Technologies GmbH & Co. KG | Seals for Fluid Power eCatalog 2014
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