Project Overview

Guyana’s construction and open-pit sites are wet, muddy, and gritty – tough on any crane’s slewing ring. For the Kato NK300, we developed a heavy-duty external-gear ring that matches OEM specs and handles frequent heavy hoists without premature wear.

Crafted from solid 42CrMo steel, the inner raceway is integrally quenched and hardness-tested to ensure load resistance. We CNC-drill inner mounting holes and precisely space the outer holes for accurate installation. All components get a refined surface finish before assembly, removing every burr and impurity.

Gear teeth are hardened to DIN Class 7, and we add enhanced sealing plus dedicated lubrication channels to block mud and dust. Every dimension is checked against confidential drawings. Our photo documentation covers heat treatment, machining, finished product, wooden case packing, and shipping. Designed for 2,000+ hours a year, this large external ring gives Guyana’s mobile cranes the lasting rotation they need.

Technical Highlights

  • Custom triple-lip seal design to prevent dust and moisture ingress
  • Induction-hardened raceway: 55–58 HRC surface, 3.5 mm case depth
  • External gear profile: module m=6, Z=168, 20° pressure angle
  • Load capacity: 680 kN axial, 135 kNm overturning moment
  • Grease refill interval extended from 80h to 200h with polyurea-based high-temp grease
  • Pre-assembly ultrasonic inspection and 360° torque test before shipment

Project Gallery