The Hitachi EX200-2 excavator uses two types of carrier rollers – top carrier rollers and bottom carrier rollers.
Top carrier rollers:
• Part number: HH0521/HH0522 – These are the top front carrier rollers located under the front idler. They help support the weight of the tracks.
• Specifications:
- Outside Diameter: 230mm
- Width: 135mm
- Bearing type: Tapered roller bearing
- Sealed: Yes, to prevent contamination
Bottom carrier rollers:
• Part number: HH0516/HH0517 – These are the bottom front carrier rollers located behind the front idler. They also help support the weight of the tracks.
• Specifications:
- Outside Diameter: 280mm
- Width: 135mm
- Bearing type: Tapered roller bearing
- Sealed: Yes, to prevent contamination
Common problems with carrier rollers:
• Bearing wear or failure: The bearings in the carrier rollers can become worn out over time and miles of operation. This can lead to play in the carrier roller, noise or the roller seizing up.
• Cracked or damaged roller: The plastic carrier roller can develop cracks or become damaged from impacts which then requires replacement.
• Bent or misshaped roller: The carrier roller can become bent or misshaped over time which causes uneven track tracking and needs replacement.
• Corrosion: Exposure to moisture, water or chemicals can lead to corrosion of the carrier roller bearings, seals and mounting bolts or pins. China HITACHI Excavator Carrier Roller EX200-2 Supplier Corroded parts need to be replaced.
• Incorrect installation: If the carrier rollers are not installed properly according to the manufacturer’s recommendations, it can lead to premature failure or uneven wear.
Replacing the carrier rollers on a Hitachi EX200-2 excavator requires disconnecting the track, removing the old carrier rollers and then installing new or rebuilt replacement rollers and reinstalling the track. It is best done by a certified Hitachi excavator mechanic with experience in undercarriage and track work.
The typical lifespan of carrier rollers, also known as support rollers or idler rollers, can vary greatly depending on factors such as the quality of the roller, the operating conditions, and the maintenance practices followed. Generally, carrier rollers can last anywhere from 3 to 5 years or even longer if well-maintained.
Factors that can affect the lifespan of carrier rollers include:
Material: High-quality materials like reinforced steel or nylon may last longer than cheaper alternatives.
Load capacity: Overloading can cause premature wear and reduce the lifespan of the roller.
Operating conditions: Exposure to harsh environments, extreme temperatures, or abrasive materials can decrease the lifespan of the rollers.
Maintenance: Regular inspection, cleaning, and lubrication can help extend the life of the carrier rollers.
Alignment: Proper alignment of the rollers in the conveyor system can reduce uneven wear and prolong their service life.
It is essential to follow the manufacturer’s recommendations for maintenance and replacement intervals to ensure the optimal performance and longevity of carrier rollers in your specific application.
