PC210-8 Komatsu Excavator Track Carrier Roller Assembly Forged 50Mn Steel Induction Hardened Undercarriage Part
| Material: | 50Mn Forged Steel | Technique: | Closed-Die Forging |
| Hardness: | 50-55 HRC (Race), 3-5 Mm Case Depth | Roller Diameter: | 118 Mm (reference) |
| Roller Width: | 64 Mm (reference) | Shaft Diameter: | 40 Mm (reference) |
| Type: | Track Carrier Roller / Top Roller | Seal Type: | Duo-Cone Metal Face Seal |
| Surface Treatment: | Anti-Rust Oil And Primer | Warranty: | 12-18 Months |
| OEM Service: | Available | Application: | Komatsu Excavator Undercarriage |
| High Light: | Komatsu PC210-8 carrier roller,PC220-8 top roller,excavator undercarriage parts |
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This YT track carrier roller assembly is produced as a direct replacement for the Komatsu PC210-8 hydraulic excavator and is also cross-listed for the Komatsu PC220-8. The roller rides on the upper track frame and supports the return portion of the chain, which is why service engineers call it the top roller. When the top roller wears or seizes, the chain starts to sag and whip, accelerating wear across the whole undercarriage, so replacing it with a correctly matched forged roller protects the investment in the track group.
Carrier Roller Structure

- One-piece forged construction: A solid 50Mn steel forging forms the roller shell, eliminating weld seams that can crack under repeated loading cycles.
- Hardened and tempered core: Heat treatment balances a wear-resistant surface with a tough body, so the roller resists both abrasion and shock.
- 50-55 HRC running race: Induction hardening creates a hard working surface with a 3-5 mm case that keeps the chain running on a true diameter.
- Close-tolerance bore: The shaft bore is finished to tight limits to prevent wobble that would hammer the frame brackets and seals.
- Duo-cone seal system: Metal face seals keep the grease in and the dirt out, an essential feature on Komatsu machines working in dry, dusty conditions.
- Full rust protection: The finished roller is coated with anti-rust oil so it stays in prime condition even after months in a warehouse.

| Type | Model | Main Dimensions of Installation | ||||||
| A | B | D | S | M | N | G | ||
| Dozer | D5 | 200 | 170 | 175 | 47.8 | |||
| D6D/D6E | 215 | 187.5 | 188 | 47.7 | ||||
| D6H | 215 | 185 | 190 | 57.15 | ||||
| D7G | 222 | 190 | 204 | 57.3 | ||||
| D20 | 142 | 120 | 110 | 40 | 100 | 50 | 12.5 | |
| D31 | 170 | 142 | 124 | 44 | ||||
| D40 | 190 | 165 | 176 | 55 | ||||
| D50 | 190 | 165 | 176 | 55 | ||||
| D60 | 215 | 185 | 200 | 61 | ||||
| D80 | 210 | 180 | 212 | 58 | ||||
The models above are just for reference, we can't list all models here. We can supply more products as your requirements. Please feel free to send us your inquiry.
Technical SpecificationsThe values below are the YT reference data for the carrier roller serving the Komatsu PC210-8 and the Komatsu PC220-8. Use them to pre-match the part before removing the machine track assembly.
| Item | Specification |
|---|---|
| Part No. | YT-PC2108-CR660 |
| Machine Model | Komatsu PC210-8 / PC220-8 |
| Roller Diameter | 118 mm |
| Roller Width | 64 mm |
| Shaft Diameter | 40 mm |
| Material | 50Mn Forged Steel |
| Hardness (Race) | 50-55 HRC |
| Hardened Case Depth | 3-5 mm |
| Weight | 10.9 kg |
| Seal Type | Duo-Cone Metal Face Seal |
| Surface Treatment | Anti-Rust Oil + Primer |
| Compatible Machine Model | Machine Class | Reference Note |
|---|---|---|
| Komatsu PC210-8 | 20.9 t crawler excavator | Main fitment of this listing |
| Komatsu PC210LC-8 | Long-track version | Same carrier roller family, verify rail spacing |
| Komatsu PC220-8 | 22.9 t crawler excavator | Secondary fitment of this listing |
| Komatsu PC220LC-8 | Long-track version | Confirm shaft diameter before ordering |
| Komatsu PC200-8 | Similar undercarriage class | Cross fit possible after dimension check |
| Komatsu PC200LC-8 | Similar undercarriage class | Verify roller width with YT before purchase |
*Values are reference; OEM part number confirmation advised before ordering.
Production Process
- Every steel lot is checked with a spectrometer on arrival to confirm the 50Mn composition.
- Sawn billets are induction heated to the forging window with tight temperature control.
- The roller shell is shaped in closed dies on a forging press, forming the flange and race profile.
- Normalizing and quench-tempering treatments create the required core toughness and machinability.
- CNC machining completes the bore, race and flange geometry with accurate concentricity.
- Medium-frequency induction hardening raises the race hardness to 50-55 HRC.
- Cylindrical grinding restores the final dimensions and surface finish after heat treatment.
- Seals and grease are installed in a controlled assembly step with cleanliness checks.
- Each batch is sampled for hardness, inspected for surface cracks and measured for key dimensions.
- Anti-rust treatment and export packing complete the production flow.

XIAMEN YINTAI MACHINERY CO., LTD., the company behind the YT brand, has specialized in undercarriage parts since 2011. The manufacturer and exporter employs 50-100 people, records annual sales of USD 10-20 million and directs 90-100 percent of production to export markets. In-house forging, CNC processing, heat treatment and induction hardening equipment give the plant complete command of the roller manufacturing chain.
YT operates under ISO 9001:2015 with documented inspection at incoming, in-process and final stages, and customers can arrange SGS verification before shipment. OEM and ODM cooperation is welcomed, and the sales team regularly helps overseas distributors build model coverage lists for popular Komatsu excavator ranges.
Solutions- Rental fleet protection: Rental companies running PC210-8 machines through multiple operators benefit from a durable top roller that keeps maintenance intervals predictable and machines available.
- Breakdown response: A seized carrier roller can stop a machine in hours; YT keeps popular sizes in stock so urgent orders ship within days, not weeks.
- Planned undercarriage service: Pairing this roller with new chain, pins and bushings during a scheduled overhaul avoids repeated strip-downs and labor cost.
- Fleet standardization: Workshops maintaining both PC210-8 and PC220-8 machines can use one YT reference for both models, cutting stock value and order complexity.

Komatsu PC210-8 and PC220-8 excavators equipped with this carrier roller are typical sights on building sites, road projects, land development, water and sewer works, and aggregate handling. The component also suits machines used for material sorting and demolition support where the excavator travels frequently across hard, debris-strewn ground. Because the top roller works above the track, it is exposed to falling material and requires the protection of a sealed, hardened design like this YT part.
Frequently Asked QuestionsQ1: How can I be sure this roller matches my Komatsu machine?
Check the roller outside diameter, face width and shaft bore against your old part, or provide the machine serial number and YT will confirm the correct reference before dispatch.
Q2: Do you sell genuine Komatsu parts?
No, YT supplies aftermarket parts manufactured to match original specifications. The 50Mn forging and induction hardened race are chosen to reproduce the working characteristics of the genuine roller.
Q3: What happens if the roller diameter is slightly different from my old one?
Never fit a roller of a different diameter, because it changes the chain line and load distribution. Always confirm dimensions first, which is why the YT table values are marked as reference only.
Q4: Can you provide the roller with custom branding?
Yes, OEM/ODM services include customer part numbering, logo marking on request and custom packaging for distributors who resell under their own brand.
Q5: What is the normal lead time for an order?
Stock items ship in 5-7 days and production batches in 20-30 days. Payment can be made by T/T or L/C according to the order value and destination.
Packaging & Quality AssuranceEach roller leaves the plant coated with rust preventive, wrapped in waterproof film and packed on steel pallets or in export wooden pallets with proper bracing for sea freight. Quality assurance documents, including material certificates, hardness reports and inspection records, are provided with every delivery. YT also supports SGS or third-party pre-shipment inspection, and mixed loading with other undercarriage components is available to optimize the container utilization and freight cost.
Why Choose Us?- Through quench-tempering processes to ensure excellent mechanical properties, high strength and superior wear resistance to bending and breakage.
- Advanced Germany KUKA automatic machining center, horizontal and vertical CNC machining ensure the accuracy of assembly dimensions. This is to maximize the life span of each component and minimize production cost.
- MAKZAK Precison Finishing Machinery from Japan makes sure we have steady and good welding quality.
- We have complete production line and professional designers and working team. We can also produce any requested parts according to your blue print or samples.
