Aftermarket Arm Cylinder for Doosan Excavators
OEM-grade arm cylinder (stick cylinder) designed for Doosan crawler excavators. Built with a chrome-plated piston rod, honed barrel, and multi-stage sealing system, this cylinder ensures high-reach power, consistent digging control, and hydraulic efficiency in tough jobsite conditions.
| Cylinder Tube | Q345 / ST52 / 27SiMn / 20# Steel |
|---|---|
| Piston Rod | 45# / 40Cr / 42CrMo (Hard Chrome Plated) |
| Piston | Ductile Iron / Forged Steel (45# / 20Cr) |
| Cylinder Head | Q345 / 45# Steel / Cast Steel |
| Seals | Polyurethane (PU), NBR, FKM |
| Guide Bush | Bronze Alloy / Composite Materials |
| Ports & Fittings | Zinc-Plated Carbon Steel / Stainless Steel |
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Kinton Parts is trusted by professionals worldwide for delivering high-quality parts for excavators, bulldozers, and other construction machinery—with guaranteed performance and durability.
The arm cylinder, also known as the stick cylinder, plays a central role in the force chain of Doosan excavators. It connects the boom to the arm and controls the forward-reach and digging motion of the machine. On models like DX220LC, DH280, or DX300LC, this cylinder:
- Powers trenching, pulling, and deep excavation
- Maintains smooth arm motion under full load
- Works in tandem with boom and bucket cylinders for optimal efficiency
- Absorbs lateral pressure and rebounds from hard-soil or rocky contact
High-frequency movement, long reach, and variable digging resistance make strength and alignment critical in arm cylinder design.
Premium Material & Precision Machining
Our Doosan arm cylinders are engineered from high-strength materials and processed under tight tolerances for long-term field performance:
- Piston Rod: 42CrMo alloy steel, induction hardened, chrome-plated ≥25μm, polished to Ra ≤ 0.2μm
- Cylinder Barrel: Honed ST52 / Q345B / 27SiMn steel tube, seamless construction for better pressure handling
- End Caps & Pistons: CNC-machined for perfect axial alignment
- Bore & Stroke Accuracy: Controlled within ±0.05mm to reduce seal wear and energy loss
- Welds: Robotic MIG welded and ultrasonic-inspected for leak-free integrity
Cross-Section Diagram
The detailed diagram allows customers to visually understand piston structure, sealing layout, and fluid channel design. It highlights the precise assembly and robust internal construction.
This diagram helps visualize how the rod, piston, barrel, and seals interact under pressure, showing key wear zones and sealing points for effective maintenance planning.
Manufacturing Process Overview
Showcasing these three key manufacturing stages can help build trust and transparency：
Rod Polishing & Surface Prep
The piston rod is ground and polished to achieve a mirror-smooth surface, ready for hard chrome plating. This step reduces wear on seals and ensures long-lasting hydraulic performance.
Assembly & Sealing
In a cleanroom assembly area, the barrel, piston, rod, and end caps are fitted and torqued to spec. Seal kits are carefully installed to prevent fluid loss and contamination.
Pressure Testing & Export Packaging
Each cylinder is tested to withstand 1.5× working pressure and checked for leaks, stroke alignment, and valve performance. Final products are sealed and packed in export-grade wooden crates.
OEM Undercarriage Parts for Doosan Excavator
| BRAND | MACHINERY MODEL NUMBER | |||||||
|---|---|---|---|---|---|---|---|---|
| DOOSAN | DH30 | DH35 | DH50 | DH55 | DH60 | DH60-7 | DH80 | DH130 |
| DH130-2 | DH150LC-7 | DH150W-7 | DH170 | DH180 | DH200W | DH210W-7 | DH220LC | |
| DH225LC | DH220LC-7 | DH225LC-7 | DH280LC | DH300-5 | DH300-7 | DH300LC-7 | DH320 | |
| DH370LC-7 | DH400LC-7 | DH450 | DX55 | DX60 | DX80 | DX140LC | DX160LC | |
| DX200A | DX225LC | DX260LC | DX300LCA | DX340LC | DX420LC | DX500LC | DX800LC | |
Looking for a specific make or model not listed here? Reach out and we’ll be happy to assist.
Compatible Doosan Models
Our Doosan arm cylinders support a wide range of models:
- DX220 / DX225 / DX260 / DX300 / DX340 / DX420
- DH220 / DH225LC / DH280 / DH300 / DH370-7
Additional models upon request
Send us your old casting number, OEM part number, or mounting dimensions—we’ll verify match within 12 hours.
Maintenance Tips for Arm Cylinders
- Wipe down and inspect the piston rod for pitting or scoring every 300–500 hours
- Monitor for signs of arm drift, hydraulic noise, or jerky motion—may indicate internal seal wear
- Keep pin joints and bushings greased to reduce shock loads
- During storage or idle periods, fully retract the cylinder to protect the rod surface from corrosion
- Avoid sudden pressure surges or full-load retraction in rocky or high-impact conditions
SHIPPING & DELIVERY
At Kinton Parts, we ensure reliable, worldwide shipping of parts for excavators, bulldozers, and a full range of construction machines—safe, fast, and secure.
All products are securely packed using high-quality export cartons, reinforced wooden cases, or industry-standard palletized packaging to ensure maximum protection during transit and smooth handling during unloading.
Standard orders are typically shipped within 3–5 working days, while large or customized orders are usually dispatched within 7–20 days, depending on volume and production requirements.
We offer flexible global shipping options, including:
- International sea freight for cost-effective bulk transport
- Air freight for urgent orders
- Courier delivery (DHL, FedEx, UPS) for small-volume or sample shipments
Our logistics team manages every shipment carefully, providing real-time updates and tracking information until your order arrives safely at your destination.
Need assistance choosing the best shipping method for your location and timeline? Contact our team — we’ll help you plan a smooth delivery experience.
FAQ
Q: What are your main products?
A: We supply a full range of undercarriage and wear parts for excavators, bulldozers, and other heavy equipment. Our product line includes: Track rollers, carrier rollers, front idlers, sprockets, segments, track shoes, track chains, bolt and nuts, pins and bushings, bucket teeth and adaptors, filters, seal kits, swing bearing, and hydraulic cylinder—plus other essential replacement parts.
Q: Which countries do you export to?
A: Kinton Parts exports to over 60 countries worldwide, including:
USA, Canada, UK, Germany, Russia, UAE, Indonesia, Malaysia, Thailand, India, Pakistan, Bangladesh, Sri Lanka, South Africa, Colombia, Peru, and many others.
Q: Can I order a sample?
A: Yes, we accept trial orders. For parts in stock, samples can be shipped quickly. If you have technical drawings or existing samples, we also support customized production and mold development.
Q: How can I track my order after shipping?
A: Once your order is shipped, we will provide you with all necessary tracking information based on the shipping method. For express deliveries, you’ll receive a tracking number to follow the shipment online. For air or sea freight, we’ll send you the relevant documents such as the airway bill (AWB) or bill of lading (B/L), along with the packing list and commercial invoice to help with tracking and customs clearance.
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Trusted by professionals worldwide, Kinton Parts supplies premium-quality components for excavators, bulldozers, and more—with reliable quality you can count on.
