Doosan DX340LC-7 Top Roller / Carrier Roller 200105-00003A – Heavy-Duty Undercarriage Component

Description

The Doosan DX340LC-7 Top Roller, part number 200105-00003A, also widely known as an upper roller or carrier roller, is an essential component of your excavator’s undercarriage system. Strategically positioned on the upper side of the track frame, its primary function is to support the weight of the track chain, preventing excessive sag between the idler and sprocket. This ensures the track maintains proper tension and alignment, allowing it to glide smoothly and efficiently, thereby reducing friction and wear on other costly undercarriage parts such as track links and idlers. This top roller is explicitly compatible with Doosan DX300LC, DX300LCA, DX340LC, DX350LC, and Daewoo DX300, DX340, SOLAR-340-7 models. Given the direct lineage and design commonalities, this part is the correct and highly suitable component for your DX340LC-7 excavator.

Manufactured to stringent OEM standards, this top roller is typically constructed from high-strength, heat-treated alloy steel (e.g., 40/50Mn carbon steel) through advanced forging, casting, and precision machining techniques. Its robust design, with a confirmed weight of 27 kg, is built to withstand the continuous stress of supporting the heavy track chain and the impacts from challenging terrain inherent in heavy excavation work. The roller’s running surface is meticulously heat-treated, achieving optimal hardness (typically HRC52-58 with a hardened depth of 8-12mm) and exceptional wear resistance, crucial for longevity due to its constant contact with the track links. The assembly is designed to be sealed and lubricated for life, incorporating high-quality seals (often heavy-duty floating seals) and internal oil lubrication that prevent the ingress of harmful contaminants like dirt, sand, and moisture. This sealed, maintenance-free design ensures smooth, low-friction rotation and significantly contributes to the component’s extended service life. Key dimensions typically include an approximate tread diameter of 142mm, flange outside diameter of 175mm, total roller width of 334mm, and a shaft diameter of 55mm.

A worn or failing top roller can lead to a range of severe operational issues, including excessive track slack, increased vibration, accelerated wear on track links, and potential de-tracking. These problems compromise machine stability, reduce operational efficiency, and can result in significant repair costs and unplanned downtime. Replacing a faulty top roller with a high-quality, OEM-standard part like the 200105-00003A is paramount for restoring optimal machine mobility, ensuring track system integrity, safeguarding your substantial undercarriage investment, and maximizing operational uptime. This carrier roller is an indispensable replacement for routine maintenance or when addressing specific issues related to track support and guidance.

Key Features:

• OEM-Quality Part: Guarantees a precise fit, uncompromised quality, and reliable performance, meeting or exceeding original factory specifications for Doosan DX340LC-7 and compatible heavy excavators.
• High-Strength Alloy Steel Construction: Fabricated from premium cast/forged alloy steel (e.g., 40/50Mn carbon steel) for maximum durability and robust resistance to wear and impact.
• Advanced Heat Treatment: Features a deeply hardened running surface (HRC52-58, depth 8-12mm typical) for exceptional longevity in challenging operating environments.
• Sealed & Lubricated for Life: Equipped with heavy-duty seals and internal lubrication to ensure maintenance-free, smooth rotation and superior protection against contaminants.
• Optimal Track Support: Engineered to effectively support the track chain, reducing sag and maintaining proper tension and alignment.
• Robust Weight: Confirmed at 27 kg, indicating a solid and appropriately sized component for heavy-duty excavator applications.

Benefits:

• Ensures Smooth Track Movement: Facilitates continuous, low-friction operation of the track chain, improving overall machine efficiency.
• Reduces Component Wear: By maintaining proper track alignment and tension, it significantly minimizes wear on track links, sprockets, and idlers.
• Improves Machine Stability & Control: Contributes to stable and controlled operation, reducing vibrations and enhancing operator comfort.
• Superior Durability: Built to withstand demanding working conditions and heavy loads, providing long service intervals and reliable performance.
• Minimizes Downtime & Costs: High-quality construction and a sealed design reduce the likelihood of unexpected failures, helping to prevent extensive repairs and maximize operational uptime.
• Resistant to Contamination: Advanced sealing technology protects internal components from dirt, moisture, and debris, ensuring consistent performance.