The Parker Prädifa KA rotary sealing set is a compact seal for sealing the high-pressure channels of rotary transmissions. It consists of a rubber element with a fabric-reinforced running surface and two anti-extrusion rings. They increase stability and prevent extrusion into the gap which due to the rotary motion (eccentricity) is variable in most cases. Due to the special shape of the dynamic sealing area, a lubricant deposit is formed which ensures the preservation of the liquid film and thereby prevents dry running.
- Enhanced sealing performance in non-pressurized conditions.
- Robust seal profile for harshest operating conditions.
- Extreme wear resistance.
- Insensitive to pressure peaks.
- High-temperature resistance in case of suitable compound selection.
- Extremely high extrusion resistance.
- Installation in closed and undercut housings.
Range of application
Mainly for applications where the pressure alternates from one side of the seal to the other, such as pivots for rotating track rings, swivel joints, hose reels, and in machine tool hydraulics.
≤ 60 °C ≤ 400 bar
≤ 80 °C ≤ 315 bar
≤ 100 °C ≤ 250 bar
Operating temperature -30 °C to +100 °C
Sliding speed ≤ 0.2 m/s
Recommendation for rotary transmissions: P ∙ v ≤ 50
(For definition see catalog „Hydraulic Seals”, chapter „Rotary seals”, introduction.)
The standard compound for the Paker Praedifa sealing part is an NBR-based elastomer with a fabric-reinforced dynamic surface (Z5011/Z5014). The back-up rings are made of a polyamide-based material.
The profile KA rotary sealing sets are designed to be snapped into closed grooves. Special versions for open grooves in end seal applications are available. During installation, first, the sealing part must be installed, followed by the back-up ring. To avoid damaging the seal, sharp edges within the installation area should be removed.