Symmetrical Rod Seal U-Cup

Symmetrical Rod Seal U-Cup

Series 106: Symmetrical Rod Seal U-Cup

The 106 Series U-Cup is a popular System Seals design used in standard duty applications. Its symmetrical design creates equal seal force across both seal lips. This gives the seal the capability to function as both a piston seal and rod seal or alternatively to seal dynamically on both the outside and inside diameters. This feature is often appreciated when reduced product inventories are desired. Manufactured in a variety of materials and sizes from 6 mm to 2100 mm in standard or custom diameters.


Symmetrical Rod Seal U-Cup


High pressure capability and wide temperature range

Excellent fluid compatibility including water-based fluids (H-PU)

Exceptional abrasion resistance

Highly extrusion resistant

Available in diameters up to 2100 mm


The 106 Series U-Cup, due to its versatility as both a piston and rod seal, can be used in a wide variety of applications. Recommended where dynamic sealing action is required simultaneously on the inside and outside diameters. Examples are often encountered in specialty sensors, bolt tension equipment and hollow cylinders.

Typical applications include:

  • Mobile Hydraulics
  • Hydraulic Cylinder Rebuild
  • Agricultural Hydraulics
  • Construction Equipment
  • Hydraulic Presses
  • Injection Molding Machines

The 106 Series rod seal features high-grade polyurethane. Standard materials are MP03 machined H-PU, available up to 2100 mm in diameter, MP50  and MN01 injection-molded TPU. To suit a variety of applications, the series is also available in NBR, H-NBR, EPDM and high temperature-resistant FPM.

Material Code
Polyurethane H-PU MP03
Polyurethane TPU MP50
Temperature MP03


hydraulic oil -20…+115 -5…+240 -30…+110 -20…+230
water oil emulsions (HFA) +5…+55 +40…+130 +5…+50 +40…+120
water-glycol fl uids (HFC) -20…+55 -5….+130 -30…+40 -20…+100
polyol esters (HFD) - - - -
water +5…+55 +40…+130 +5…+50 +40…+120
Speed 0.5 m/s (1.6 ft/sec)
Pressure 400 bar (6000 psi)

Note: for other materials or fluids please contact our engineering department.