Komatsu 20Y-30-00070 Floating Seal Assembly

The 20Y-30-00070 is a mechanical face seal assembly, commonly referred to as a duo cone seal or floating seal. It consists of two precision-machined hardened steel seal rings and two elastomeric toric rings (O-rings) that provide axial loading and static sealing. The metal rings rotate against each other with a thin lubricating oil film, preventing abrasive contaminants from entering the bearing cavity while retaining lubricant. This assembly is designed for the carrier roller (upper roller) and track roller positions on specific Komatsu excavator undercarriages. It is manufactured to OEM elastomer compound and dimensional specifications to ensure correct sealing contact pressure and reliable fluid containment under high-load, low-speed rotating conditions typical in construction machinery track systems. Legacy part numbers include 20R-30-00080, 20Y-30-15210, and 20Y-30-00080.