Heavy Duty Excavator Idler Assembly For PC120 Models 203-30-00210

How to Distinguish the Quality of PC120 Excavator Idler Wheels

• Check the Appearance
  1. Verify the Certificate of Conformity and Specifications: High-quality idler wheels should have an inspection certificate issued by the national quality and technical supervision department, and their specifications and models must meet the application requirements of PC120 excavators.
  2. Inspect Surface Quality: A top-quality idler wheel should be free of rust, cracks, sand holes, slag inclusions, burrs and other defects, with a complete paint film. Products with obvious surface flaws are likely to be counterfeit or shoddy goods.
  3. Examine Assembly Marks: Genuine and qualified products have clear and distinct assembly marks—such as installation hole position marks—which should be intact and legible. Idler wheels without marks or with vague marks are not recommended for purchase.
• Measure Dimensions
  1. Shaft Diameter: Generally, idler wheels with a larger shaft diameter are of better quality. For medium-sized excavators like the PC120, reliable idler wheels usually come with a larger shaft diameter, which can be measured with a caliper for quality assessment.
  2. Wheel Body Diameter: Qualified idler wheels have an outer diameter that complies with standard specifications. For example, the outer diameter of a genuine mining-grade idler wheel is 535 mm, while that of a counterfeit one is only 520 mm—measuring the outer diameter is an effective way to tell them apart.
• Evaluate Craftsmanship and Material
  1. Manufacturing Process: Forged idler wheels outperform cast ones. Forged idler wheels feature dense internal structures, high strength and toughness, as well as excellent wear resistance and fatigue resistance. In contrast, cast idler wheels may have defects such as air holes. Additionally, integrally forged idler wheels are of higher quality than roll-forged and welded ones.
  2. Wheel Body Material: Premium idler wheels are mostly made of high-hardenability cast steel or high-quality structural steel, which undergo heat treatment processes like quenching and tempering, and surface quenching. This ensures high surface hardness and good core toughness. You can check product manuals or consult suppliers to learn about the material and heat treatment process.
• Inspect the Internal Structure
  1. Bearing Quality: Most idler wheels adopt bimetallic bearings or cast copper alloy bearings inside, which should rotate flexibly with clearance meeting standard requirements. When purchasing, you can rotate the idler wheel manually—smooth rotation without jamming indicates good bearing quality.
  2. Sealing Performance: A sound sealing system prevents sand, mud and water vapor from entering. You can check whether the bearing part uses a double-lip seal ring or labyrinth seal structure, and verify the quality and proper installation of the sealing components.
• Compare Weight: For idler wheels of the same specification, heavier ones are usually better quality because they use more raw materials. For instance, a pure mining-grade idler wheel weighs 137 kg after sand cleaning, while a counterfeit one only weighs 113 kg. A simple weight comparison can be used for initial quality judgment.