Common faults of P3SA17/18 sealing protection components are concentrated in the shaft oil seal, box joint surface, oil drain/oil level plug and breather cap. The main problems are leakage, dustproof failure, aging and installation damage. The following is a pure text description.
Shaft oil seal (input/output side)
Leakage : oil droplets under the shaft end or oil accumulation on the flange. This is mostly due to the hardening, cracking, flanging or scratching of the lip by the shaft shoulder; scratches/rust/grooves on the journal that damage the fit; bearing wear causing radial runout and uneven stress on the lip; too high cavity pressure (blocked ventilation holes) to 'press out' the oil.
Dust-proof failure : Dust intrusion causes accelerated wear of oil seals and bearings; lifespan is shortened by 60%–80% under high dust conditions.
Installation damage : Failure to use special tools causes the lip to flip and the spring to fall off; the oil seal is reversed or the coaxiality is poor, and one side is worn.
Selection / Material : inconsistent with specifications (inner diameter is too small) or not resistant to temperature/corrosion, short-term aging.
Box joint surface (end cover/box)
Oil leakage: oil stains or dripping on the joint surface. This is mostly due to aging, hardening, deformation, and cracking of O-rings/gaskets; loose bolts or uneven tightening resulting in local gaps; sealant not being applied/unevenly/falling off; flatness out of tolerance (>0.03 mm/m).
Improper installation: The O-ring is scratched or not fully inserted into the groove; the joint surface is not cleaned, resulting in local gaps.
Oil drain/oil level plug seal
Leakage: Oil stains around the screw plug. This is mostly due to the aging, hardening and deformation of the sealing gasket; loosening of the bolts; worn threads or lack of anti-loosening washers.
Breathable cap (breathing valve)
Clogging: Internal pressure rises and oil is squeezed out from the oil seal or joint surface. It is usually caused by dust/sludge clogging the filter cotton; high dust environment is not cleaned in time.
Failure: The valve plate is aged or damaged and loses its pressure balancing function.
Floating oil seal (if equipped)
End face grinding/sintering: Adhesive wear and high temperature sintering of metal ring end faces. This is mostly due to excessive axial preload, too thin oil film, insufficient oil supply, dry friction, uneven assembly or twisted O-ring.
O-ring damage: deformation, hardening or sealing failure, resulting in oil leakage and dust intrusion.
