| Item | Specification |
|---|---|
| Part Number | 94428840 |
| Product Name | Top Roller / Carrier Roller Assembly |
| Product Type | Undercarriage Component |
| Compatible Machine Models | Komatsu PC4000, PC5500 Mining Excavator |
| Roller Type | Top Roller / Carrier Roller (Upper Track) |
| Single Weight | 248.3 kgs (547.4 lbs) |
| Material | High-strength alloy steel with induction-hardened wear surface |
| Sealing Type | Floating / Duo-cone seals for contamination protection |
| Application | Supports and guides the track chain in the upper section of the undercarriage |
| Industry Focus | Surface Mining, Heavy Excavation, Overburden Removal |
Komatsu 94428840 top roller
PC4000 carrier roller assembly
PC5500 top roller
Komatsu PC4000 undercarriage parts
248.3 kg top roller for PC4000 excavator
Replacement carrier roller for Komatsu PC5500
Komatsu mining excavator top roller
The Komatsu 94428840 Top Roller Assembly (Carrier Roller) is a genuine OEM-specification undercarriage component designed for the Komatsu PC4000 and PC5500 mining excavators. This top roller (carrier roller) supports the upper strand of the track chain, reducing track sag and ensuring proper alignment between the drive sprocket and idler.
The PC4000 and PC5500 are ultra-class mining excavators used in large-scale surface mining, heavy excavation, and overburden removal. This carrier roller is manufactured from high-strength alloy steel with induction-hardened tread surfaces for maximum wear resistance in abrasive mining conditions.
| Feature | Benefit |
|---|---|
| Top Roller / Carrier Design | Supports upper track chain, reducing sag and vibration |
| Induction-Hardened Tread Surface | Exceptional wear resistance in extreme mining conditions |
| Floating / Duo-Cone Seals | Advanced sealing prevents contamination and retains lubrication |
| Precision Bearings | Smooth rotation with minimal friction for extended service life |
| Heavy-Duty Construction (248.3 kg) | Robust build for ultra-class mining applications |
| PC4000/PC5500 Optimized | Specifically engineered for Komatsu PC4000 and PC5500 |
| Factory Lubricated | Maintenance-free sealed design |
| Direct OEM Replacement | Guaranteed fit and performance |
| Specification | PC4000 | PC5500 |
|---|---|---|
| Operating Weight | ~400,000 - 450,000 kg | ~500,000 - 550,000 kg |
| Bucket Capacity | ~22.0 - 28.0 m³ | ~28.0 - 34.0 m³ |
| Engine Power | ~1,800 - 2,000 HP | ~2,200 - 2,500 HP |
| Position | Top / Upper track (Carrier Roller) | Top / Upper track (Carrier Roller) |
| Component | Part Number | Description |
|---|---|---|
| Idler (PC4000) | 42969740 / 97077040 | Front idler assembly (2,528 kg) |
| Sprocket (PC4000) | 88711040 / 97080240 / 64394040 | Drive sprocket |
| Top Roller | 94428840 | Carrier roller (248.3 kg) |
| Bottom Roller (PC4000) | 89590440 | Track roller (493.6 kg) |
Position: This is a top/carrier roller - supports the upper track strand
Lifting Requirement: Due to weight (248.3 kg), specialized lifting equipment and mechanical assistance are required
Bolt Torque: Follow Komatsu OEM specifications for mounting bolt torque
Regular Inspection: Check for seal damage, bearing wear, and tread wear periodically
Lubrication: Factory-sealed; no field lubrication required
Replacement: Replace when tread wear exceeds OEM specifications or when seal failure occurs
| Condition | Action |
|---|---|
| New tread - smooth rotation | Normal operation |
| Moderate tread wear | Monitor regularly |
| Excessive tread wear (flat spots) | Replace roller |
| Seal leakage | Replace roller immediately |
| Bearing noise/play | Replace roller |
| Item | Detail |
|---|---|
| Part Number | 94428840 |
| Type | Top Roller / Carrier Roller Assembly |
| Weight | 248.3 kg per piece |
| Compatibility | Komatsu PC4000, PC5500 Mining Excavator |
| Packaging | Individual crate |
Note: This is a top/carrier roller for the Komatsu PC4000 and PC5500 ultra-class mining excavators. Verify machine serial number and undercarriage configuration before ordering. Due to weight (248.3 kg), proper lifting techniques and mechanical assistance are required during installation. Regular inspection of carrier rollers is essential for optimal undercarriage performance on these ultra-class mining excavators.