Category Guide · September 25, 2026 · Guangzhou, China
Excavator Undercarriage Parts: Rollers, Idlers, Sprockets and Track Groups
Undercarriage can consume up to twenty percent of an excavator's total operating cost, and unlike engines or hydraulics, it wears out on every machine, every day. That makes it one of the most price-shopped categories in the parts trade — and also the one where the cheapest quote is most often the most expensive decision. Corbay is the international export brand of Guangzhou Shenyue Machinery Technology Co., Ltd., Guangzhou, China. We supply undercarriage components across Kobelco, Komatsu, Hitachi, Caterpillar, Sany, XCMG, Doosan, Hyundai and other makes, and this guide is what we tell every buyer before the first roller order.
What the Undercarriage Actually Includes
Track rollers (bottom rollers) that carry the machine's weight on the rail, and carrier rollers (top rollers) that support the returning chain.
Idlers and tension assemblies at the front, guiding the chain and absorbing shock through the recoil spring.
Sprockets and segments that drive the chain — and wear fastest, because they work by engaging metal on metal.
Track groups: links, pins, bushings and shoes, ordered as complete groups or as separate shoes. The photograph on this page shows a typical multi-brand undercarriage range on our floor — see our
parts catalog for the categories we quote.
What Really Decides Wear Life
Material and heat-treatment depth.Roller shells and link rails need deep, uniform surface hardening over a tough core. Shallow hardening looks fine on day one and is gone by mid-life.
Sealing quality.A roller is only as good as its seals — grit past a cheap seal destroys the internal bushings and pin ends long before the shell wears out.
Track tension and alignment.Over-tight tracks multiply wear on every component; loose tracks slam the rails and chew sprocket teeth. Tension is a maintenance habit, not a parts quality issue — but it decides whether good parts reach their design life.
Working conditions.Rock, abrasion and frequent reverse travel all shorten life; the parts spec should match the site, and we will ask about conditions before recommending a grade.
Genuine, OEM or Aftermarket Undercarriage?
Genuine from the machine maker's channel gives full traceability — see the
machine manufacturers' own parts documentation for how original references are structured.
OEM-quality components come from the same foundry and forging base that supplies the original makers, at a substantial saving — usually the sweet spot for machines out of warranty.
Aftermarket is legitimate only when the manufacturer is named and the heat treatment is specified. Anonymous castings with no hardness data are where the false economy lives.
Guangzhou Shenyue Machinery Technology Co., Ltd. quotes undercarriage lines grade by grade, with the origin of each option stated in writing. For buyers running mixed fleets, our global supply page shows how we consolidate undercarriage with engine, hydraulic and filter items in the same shipment.
How to Order Undercarriage Without Guessing
Machine model and serial number — shoe widths, roller counts and pitch changed between generations of the same model.
Photos of the worn parts, including any casting numbers, and the measuring points: roller diameter and flange positions, shoe width and pitch, link count.
The working conditions — we match the grade to the site, not just to the machine.
Quantity and destination port.Undercarriage is heavy; sea freight economics and consolidation matter, and we plan the packing with you.
Undercarriage Parts — FAQ
Should rollers be replaced before they fail completely?Ideally no — running a roller until it seizes drags the rail and can take the track group with it. Measuring remaining shell diameter at service intervals and replacing at the wear limit is the cheap way to do it.
Do you supply undercarriage for machines other than Kobelco?Yes — rollers, idlers, sprockets and track groups are quoted across Komatsu, Hitachi, Caterpillar, Sany, XCMG, Doosan and Hyundai. For Kobelco-specific model depth, our dedicated resource site
shenyuekobelco.com covers the SK series in detail.
How do I request a quotation and how fast will I get a reply?Send the machine model and serial, photos and measurements of the parts, quantity and destination port via the contact page — Guangzhou Shenyue Machinery Technology Co., Ltd. normally replies within 24 hours with grades and freight options on the same quotation.
Send Photos and Measurements, Get a Quote That Fits
Undercarriage rewards buyers who measure. Send the machine model and serial, photos of the worn parts, and the destination port, and the team at Guangzhou Shenyue Machinery Technology Co., Ltd. will match the parts, quote every grade, and plan the packing for the cheapest safe freight.
Corbay Excavator Parts is the international export brand of Shenyue Machinery (Guangzhou Shenyue Machinery Technology Co., Ltd.), Guangzhou, China. Shenyue is an independent parts specialist and is not affiliated with, or an authorized dealer of, Kobelco Limited. Parts are supplied as genuine, OEM or clearly identified aftermarket items, and the grade is stated on every quotation.
