Four-Piece Rod Seal With Active Backup Rings

Series 128: Four-Piece Rod Seal With Active Backup Rings

The 128 series is one of the most robust four-piece rod seals on the market. It consists of a profiled energizer, a polyurethane seal element and two active anti-extrusion backup rings. It is designed for double-acting cylinders in heavy-duty applications subject to severe pressure spikes coupled with high running clearance.



Long service life under the harshest conditions

Compatible with water-based fluids (H-PU)

Optimized for high running clearance

Easy installation



The 128 series, four-piece rod seal is ideal in heavy duty sealing applications where pressure spiking can occur.

Typical applications include:

  • Mining
  • Heavy duty clamp cylinders
  • Specialty high-pressure cylinders
  • Hydraulic rams
  • Various advancing and secondary cylinders

The 128 series rod seal features a robust NBR elastomer, a profiled seal ring in abrasion resistant polyurethane and two backup rings in high-strength thermoplastic.

Material Code
Polyurethane H-PU / NBR / POM MP38
Polyurethane H-PU / NBR / Polyamide MP40
Temperature MP38

hydraulic oil -20…+115 -5…+240
water oil emulsions (HFA) +5…+55 +40…+130
water-glycol fl uids (HFC) -20…+55 -5….+130
water +5…+55 +40…+130
Speed 0.5 m/s (1.6 ft/sec)
Pressure 1380 bar (20000 psi)

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