Precision Machining for Hydraulic System Components
Where Pressure Meets Precision — High-Integrity Parts for Fluid Power Systems
Hydraulic systems power the toughest machines on earth — from excavators and cranes to industrial presses and marine systems. The components that withstand up to 700 bar of pressure must be machined to perfection. From deep-bored cylinders to fine-finished pistons and leak-free end caps, every micron matters.
Our CNC facility in China has 20+ years of experience delivering critical hydraulic motion parts to global OEMs in heavy equipment, offshore platforms, and automated machinery. We bring full control over machining, sealing surface integrity, heat treatment, and high-pressure test validation.
✔ Why Hydraulic Parts Are So Difficult to Machine
Hydraulic components must survive extreme loads, wear, and tight sealing conditions. Key machining challenges include:
- Deep bore concentricity: Cylinder bores up to 1500mm length must stay within 0.01mm straightness.
- Surface roughness for sealing: Rods and seats require Ra < 0.2μm to ensure zero leakage.
- Thread + groove tolerance: Precision in O-ring and wear ring grooves is vital for longevity.
- Chrome/hard coatings post-processing: Plated parts must be ground or polished to final spec.
- Flatness & parallelism: End caps and valves require <0.01mm deviation for sealing surfaces.
✔ Key Hydraulic Components We Machine
| Component | Application | Machining Features |
|---|---|---|
| Hydraulic Cylinder Tubes | Excavators, presses | Bore ID Ra 0.4–0.8μm, honing or boring < 0.01mm tolerance |
| Piston Rods / Shafts | Presses, injectors, marine | Chrome plated + polished Ra < 0.2μm, straightness ≤ 0.01mm |
| Cylinder End Caps / Glands | All mobile hydraulics | Precision threads + groove machining for O-rings |
| Sliders / Bushings / Wear Rings | Hydraulic servo & actuators | Wear-resistant alloys, tight roundness < 0.005mm |
| Gear Pump Casings / Rotors | Agricultural, forklift systems | Involute gear cavity + tight parallelism in body halves |
| Custom Valve Blocks | Injection molding, mining | Multi-face drilling with ±0.01mm port positioning |
✔ Materials & Finishes We Handle
| Material | Treatment | Use Case |
|---|---|---|
| CK45 / 1045 / S45C | Induction hardened + plated | Standard piston rods and tubes |
| 42CrMo4 / SCM440 | Quenched + tempered + chromed | High strength hydraulic shafts |
| Stainless Steel 304 / 431 / 17-4PH | H900 / passivation | Corrosive fluid & food-grade hydraulics |
| Bronze / Brass / PTFE Composites | Machined or cast bushing | Low friction, high-wear guides |
| Ductile Iron / GGG40-70 | Nitrided or phosphate | Pump casings and heavy end caps |
We also provide chrome plating, nickel plating, chemical blackening, and hard oxide or anodizing for aluminum blocks.
✔ Our Machining Capabilities for Hydraulic Parts
- Deep-hole boring and honing (ID tolerance ±0.01mm)
- Cylindrical grinding for rods up to 2,000mm
- Thread milling for UN/ORFS/BSP/NPT hydraulic ports
- Groove cutting for O-rings, U-cups, and back-up rings
- 5-axis milling for complex valve blocks and manifolds
- High-pressure leak testing up to 600 bar (on request)
Inspection tools:
- Air plug gauges & CMMs for port alignment
- Roundness testers and bore scopes for cylinder ID
- Surface roughness testers (Ra 0.1μm–1.6μm range)
- Thread profile gauges for UN/metric/BSP types
- Hydraulic simulator test rigs (optional)
✔ Global Reference Projects
- ✅ Rod & gland machining for U.S. agricultural cylinder supplier
- ✅ Valve blocks for Italian injection molding equipment (Ra < 0.4μm)
- ✅ End caps for German high-pressure servo cylinders
- ✅ Marine-grade hydraulic rod sets (SUS431 polished + ground) for Korean shipbuilder
✔ Why Global OEMs Trust Our Hydraulic Machining
- 💧 Deep expertise in pressure-rated, sealing-critical parts
- 🔍 Integration of honing, polishing, deep boring, and groove finishing
- 📈 Documentation: Full inspection reports, material traceability, PPAP (optional)
- 🌍 Exports to Europe, U.S., Korea, Southeast Asia in ISO and CE-compliant systems
- 🕒 Fast turnarounds: Prototypes in 7–12 days, production scaling supported
🛠️ Strength Under Pressure — Built with CNC Precision
From heavy construction cylinders to compact servo actuators, we supply machined hydraulic components that stand up to the toughest jobs — cycle after cycle, without leaks, wear, or drift.
📩 Need a quote? Upload your drawings or 3D files — we respond in 24 hours.