The Korean Parts Makers Supplying Global OEMs That Really Power Excavators and Loaders

The names HD Hyundai Construction Equipment, HD Hyundai Infracore, Doosan Bobcat, and Volvo Construction Equipment are familiar enough. But if you watch job sites long enough, your focus starts to shift a bit further back. What actually supports the moment an excavator or loader plants itself in the dirt, lifts its boom, and swings its bucket are the components underneath it all: undercarriages, hydraulics, electrical systems, and attachments. More interestingly, these companies are not just domestic suppliers to finished equipment makers. They are B2B heavyweights that supply directly to global OEMs such as Caterpillar, Volvo, Komatsu, and John Deere.

If you read the construction equipment sector only through the lens of finished machines, you are seeing only half the picture; the real resilience comes from parts makers that supply across multiple global OEMs. If you ask why that matters even more now, the answer is straightforward. U.S. infrastructure investment, reshoring, data center construction, and mining demand are all underpinning the equipment cycle. Parts suppliers are not tied solely to the sales swings of any single equipment maker. On top of that, the shift toward electric excavators and automation is creating new demand for hydraulic and electrical components. Even if the face of finished equipment changes, the internal organs and structural backbone only become more important. That is exactly the phase we are in now.

Undercarriages & Forgings — the Structural Backbone That Grips the Ground (4 companies)

Undercarriages, forgings, and cast steel parts are not glamorous. But they are the first components to wear out and the clearest places where performance differences show up when an excavator has to hold its ground and keep turning on dirt. Track rollers, idlers, track links, track shoes, and large cast steel components may not stand out visually, but they determine equipment durability and cost.

The real competitive edge of Korea’s undercarriage and forging players is not that they serve as subcontractors to domestic OEMs, but that they sell directly to global customers like Caterpillar, Volvo, and Komatsu. Jin Sung T.E.C. is one of Korea’s leading companies in undercarriage track rollers, idlers, and track links, with a high sales mix to Caterpillar. Daechang Forging supplies heavy equipment forged parts such as track links and track shoes to Caterpillar, HD Hyundai, Volvo, Komatsu, and John Deere. Heungkuk delivers track rollers, carrier rollers, idlers, and tension cylinders to Volvo and HD Hyundai Construction Equipment. Dongil Metal produces large cast steel components for construction machinery and cranes at an annual capacity of around 20,000 tons, supplying global customers including Manitowoc. Companies like these can partially cushion the blow with other OEMs and regional demand even if equipment sales slow at one brand. On the ground, that diversification matters more than people think. Quite often, what matters more than whose machines are selling best is who gets designed into multiple machines at the same time.

Company	Core focus
Jin Sung T.E.C.	Undercarriage track rollers, idlers, and track links — a leading Korean supplier with high exposure to Caterpillar
Daechang Forging	Heavy equipment forged parts including track links and track shoes — supplies Caterpillar, HD Hyundai, Volvo, Komatsu, and John Deere
Heungkuk	Undercarriage track rollers, carrier rollers, idlers, and tension cylinders — supplies Volvo and HD Hyundai Construction Equipment
Dongil Metal	Large cast steel components for construction machinery and cranes (around 20,000 tons annually) — global supply including Manitowoc

Hydraulics & Electrical Systems — The Muscle and Brain of Construction Equipment (3 companies)

The heart of construction equipment is not just the engine. You also need hydraulic pumps and motors, cylinders, and main control valves that turn power into actual motion—those are what move the arm and rotate the body. And these days, equipment cannot stay competitive without electrical systems. Add controllers (MCUs), clusters, and wiring harnesses, and the machine becomes more precise and a lot smarter.

As electrification and autonomy advance, the importance of hydraulic and electrical components does not shrink—it actually grows. Mottrol is Korea’s No. 1 player in hydraulic pumps, travel and swing motors, and main control valves (MCVs), and it is a subsidiary of Doosan Bobcat. Because it is unlisted, the numbers are less visible, but it is essentially a flagship name in Korea’s domestic hydraulic core components space. DY Power is Korea’s No. 1 maker of hydraulic cylinders for construction equipment, with roughly 97% of revenue coming from this segment. Its customer base is also clear: HD Hyundai Infracore, Doosan Bobcat, and Volvo. Prems is a comprehensive electrical systems company for construction equipment, supplying controllers (MCUs), clusters, and wiring harnesses to HD Hyundai Construction Equipment and HD Hyundai Infracore. Does a battery-electric excavator mean hydraulics disappear? Does autonomous equipment make wiring and control less important? Quite the opposite. As machines need finer motion control and more accurate condition monitoring, both the pricing power and the role of hydraulic and electrical systems are likely to rise together.

Company	Core focus
Mottrol	Korea’s No. 1 in hydraulic pumps, travel/swing motors, and main control valves (MCVs) — subsidiary of Doosan Bobcat (unlisted)
DY Power	Korea’s No. 1 in hydraulic cylinders for construction equipment (~97% of revenue) — HD Hyundai Infracore · Doosan Bobcat · Volvo
Prems	Comprehensive electrical systems for construction equipment (controllers/MCUs, clusters, wiring harnesses) — HD Hyundai Construction Equipment · Infracore

Attachments & Distribution — Tools and Services at the End of the Arm (4 companies)

A lot of the money in this business is made at the end of the machine’s arm. Attachments like hydraulic breakers, crushers, and quick couplers change on-site productivity and expand how equipment can be used. Add adjacent equipment such as concrete pump trucks, plus distribution and maintenance services, and it becomes an ecosystem that goes well beyond simple manufacturing.

Attachments and distribution may look like cyclical businesses, but in reality, replacement demand, service demand, and overseas sales channels provide a solid floor. Daemo Engineering is Korea’s No. 1 player in hydraulic breaker, crusher, and quick coupler attachments, and one of the world’s top three suppliers, exporting to more than 80 countries. Soosan Cebotics, formerly Soosan Heavy Industries, makes hydraulic breakers and attachments, while also producing specialty equipment such as hydraulic drills and cranes. Hyundai Everdigm, formerly Everdigm, offers concrete pump trucks, attachments, fire trucks, and tower cranes, and is part of the Hyundai Department Store Group. Hyein is the official domestic dealer for Caterpillar construction equipment, handling both distribution and maintenance. It’s an industry truism that the service that keeps a machine running generates longer-lasting value than the one-time sale of the machine itself. Once parts, attachments, and a dealer network are in place, the downcycle tends to be shallower than it looks.

Company	Core Business
Daemo Engineering	Korea’s No. 1 in hydraulic breaker, crusher, and quick coupler attachments — exports to 80+ countries (global top 3)
Soosan Cebotics (formerly Soosan Heavy Industries)	Hydraulic breakers and attachments + specialty equipment (hydraulic drills, cranes)
Hyundai Everdigm (formerly Everdigm)	Concrete pump trucks, attachments, fire trucks, and tower cranes — Hyundai Department Store Group
Hyein	Official domestic dealer and maintenance provider for Caterpillar construction equipment (distribution and service)

What to Watch Going Forward

The road ahead looks fairly clear. U.S. infrastructure investment and reshoring will spur civil works and factory construction, data center buildouts will extend equipment operating hours, and mining demand will support the flow of large machinery and consumable parts. Automakers may see more pronounced swings by brand, but parts suppliers become more resilient the more they diversify deliveries across multiple OEMs and multiple regions. That is exactly why Korea’s undercarriage, forging, hydraulics, electrical systems, and attachment makers stand out. A business structure tied not to the sales volume of a single company but simultaneously to the production plans of many companies is sturdier than it looks.

The real battleground in the next cycle is not a single automaker selling the most units, but parts suppliers with diversified global customers and companies that move first to capture demand for electrification and automation. Electric excavators and autonomous equipment are new, but they are not entirely unfamiliar markets. Hydraulics need to become more precise, and electrical systems more complex. The value of service and maintenance will also rise. That is why, when looking at construction machinery, focusing only on the OEM logo means you keep missing what really matters. In the end, what keeps jobsites running is the unseen parts behind the machines and the B2B specialists that supply them consistently.

※ This article organizes company names, core businesses, and market positions based on publicly available materials verified online, and some assessments reflect the author’s own views. It is not intended as a direct basis for investment decisions.

Written: July 2026. Ealexandro