KOMATSU KM3244 / 2093000300 PC750 / PC800 / Carrier Roller / Upper Roller Assembly manufactured by HELI CQCTRACK

High-performance KOMATSU PC750 & PC800 carrier roller assembly (P/N: KM3244, 2093000300). Expertly manufactured by HE LI CQCTRACK for superior durability in heavy-duty undercarriage applications. OEM-compatible quality.

Content:

Introduction: The Critical Role of Carrier Rollers in Excavator Undercarriage Systems

Within the robust track chassis of large hydraulic excavators like the KOMATSU PC750 and PC800, the upper structure’s weight is distributed and guided by a series of precision components. Among these, the Carrier Roller (Upper Roller) Assembly plays an indispensable role. Positioned atop the track frame, these rollers support the upper run of the track chain, maintaining proper track sag (tension), guiding the track’s return path, and minimizing lateral oscillation. For mining, quarrying, and heavy excavation applications typical of the PC750/PC800 series, the reliability of these rollers directly impacts machine stability, track life, and overall undercarriage health.

Technical Specifications: KOMATSU KM3244 / 2093000300 Carrier Roller Assembly

This specific assembly is engineered as a direct replacement for the OEM carrier roller on KOMATSU PC750-6, PC750SE-6, PC800-6, and compatible models. It is designed to meet the exact dimensional, load-bearing, and performance specifications required by these machines.

• OEM Part Number Reference: KM3244, 2093000300
• Application: KOMATSU PC750, PC800 series excavators.
• Type: Upper Carrier Roller (Return Roller).
• Function: Supports the upper track chain, maintains track tension, reduces friction and wear during track return.

Engineering & Manufacturing Analysis by HE LI (CQCTRACK)

HE LI, operating under the industrial brand CQCTRACK, specializes in the manufacture of heavy-duty undercarriage components. Their production of the KM3244/2093000300 Carrier Roller Assembly follows a rigorous engineering and manufacturing protocol:

1. Advanced Material Selection & Forging:

• The roller outer shell is forged from high-grade medium-carbon alloy steel (e.g., 50Mn, 55Mn), chosen for its excellent combination of strength, toughness, and hardenability.
• Forging ensures a continuous grain flow that follows the contour of the part, significantly enhancing fatigue resistance compared to cast alternatives, which is critical for withstanding repeated high-impact loads from the track chain.

2. Precision Machining & Heat Treatment:

• CNC Machining: The forged blank undergoes precise CNC turning and grinding to achieve the specified outer diameter, flange profiles, and bore dimensions. This guarantees perfect concentricity and smooth rolling contact with the track chain links.
• Dual-Stage Heat Treatment:
  • Body Hardening: The roller body is through-hardened to a core hardness typically ranging from 50-55 HRC. This provides the necessary structural integrity to resist deformation under extreme loads.
  • Flange Hardening: The critical flange surfaces, which guide the track chain and prevent derailment, often receive induction hardening. This process creates an ultra-hard, wear-resistant layer (58-62 HRC) on the flange edges, dramatically extending service life against abrasive wear.

3. Sealed & Lubricated Bearing System:

• The heart of a reliable carrier roller is its internal bearing and sealing system. The HE LI assembly incorporates a multi-labyrinth seal configuration paired with high-quality, wear-resistant floating seals (often referred to as Duo-Cone seals).
• This system is pre-loaded with a high-temperature, high-pressure grease, creating a robust barrier against the ingress of abrasive contaminants (dust, mud, slurry) and the egress of lubricant, even under the demanding conditions faced by PC750/PC800 excavators.

4. Robust Shaft & Mounting Design:

• The internal shaft is manufactured from hardened steel, designed to fit precisely into the excavator’s track frame bracket. The assembly includes all necessary seals, spacers, and fasteners, delivered as a complete, ready-to-install unit.

Failure Mode Considerations & Value Proposition

Common failure modes for carrier rollers include flange wear, seal failure leading to bearing contamination, and roller body scoring. The HE LI (CQCTRACK) manufacturing process directly addresses these issues:

• Extended Flange Life: Enhanced hardening processes combat premature flange wear.
• Superior Sealing: Advanced seal technology minimizes the primary cause of premature bearing failure.
• Precision Fit: Accurate machining ensures optimal alignment, reducing uneven wear and strain on adjacent undercarriage components.

Why Source from HE LI (CQCTRACK)?

• OEM Compatibility: Manufactured to original KOMATSU specifications for a direct, no-modification fit.
• Durability Focus: Emphasis on material quality and hardening techniques aims to match or exceed OEM service intervals.
• Cost-Effective Maintenance: Provides a reliable, high-quality alternative for fleet managers seeking to optimize maintenance budgets without compromising equipment uptime or performance.
• Complete Assembly Supply: Delivered as a fully assembled, greased, and sealed unit, simplifying installation and reducing downtime.

Conclusion

The KOMATSU KM3244 / 2093000300 Carrier Roller Assembly is a vital wear component for maintaining the efficiency and longevity of PC750/PC800 excavator undercarriages. HE LI (CQCTRACK) applies its specialized expertise in metallurgy, precision machining, and tribology to produce a component that delivers reliable performance under severe operating conditions. For equipment owners and maintenance professionals, choosing this manufacturer represents a strategic decision to secure durable, compatible undercarriage parts that support maximum machine availability and lower total operating costs.