DWI 60x74x8 PU+Metal Material Japan Hydraulic Oil Seal Dust Wiper Seal For Hydraulic System

If there is mud and dust accumulated on the piston rod with minor oil leakage or jerky cylinder movement, it indicates failure of this DWI dust wiper. Fully depressurize the hydraulic system and drain residual hydraulic oil from the cylinder before disassembly to avoid oil ejection under pressure. Inspect the piston rod surface for scratches and rust; polish and repair damaged rod surfaces prior to seal replacement, as surface defects will rapidly abrade the PU lip of the new seal.

Only standard DWI seals with inner diameter 60mm, outer diameter 74mm and thickness 8mm are allowed for replacement; non-standard sizes are prohibited. This seal adopts Japan-formulated wear-resistant PU with reinforced metal frame. Ordinary rubber dust seals shall not be substituted, as they suffer insufficient wear resistance and lip cracking within 300 working hours in dusty environments. Discard used seals with deformed or rusted metal frames; straightening and reuse are forbidden.

Remove all burrs and thoroughly degrease the seal groove and piston rod chamfer before installation. The dust lip of the DWI seal must face outward (equipment exterior), with the metal frame side closely attached to the bottom of the cylinder end cap groove. Press the seal into place with a plastic installation guide tool; metal screwdrivers or pry bars are forbidden to prevent cutting the PU dust lip. Lightly coat the dust lip with hydraulic-resistant grease before assembly; strong acid or alkaline lubricants cannot be used to avoid corrosion of PU material.

Inspect hydraulic equipment in clean workshops every 300 working hours; check machinery working in mining and heavy dusty environments every 80 hours. Focus inspection items include dust lip abrasion, loose metal frame and dust blockage. Replace the seal immediately once slight hardening or debris shedding occurs. Delayed maintenance allows sediment to invade the main inner oil seal, leading to secondary damage of the entire rod seal kit and higher maintenance costs.

After seal assembly, reciprocate the cylinder at low speed without load for 10 cycles first, then boost pressure stepwise to the rated hydraulic pressure and hold pressure for 15 minutes. If oil leakage persists after replacement, overhaul the inner main oil seal and guide sleeve clearance simultaneously. For operating conditions with continuous high oil temperature above 60°C, install an external dust shield post maintenance to slow thermal aging of PU and extend seal replacement intervals.