The hydraulic directional control valve body from Ningbo Ruican is the core component of hydraulic systems used in construction machinery, agricultural equipment, and industrial machinery. This valve body directs hydraulic fluid flow between different circuits, controlling the direction of actuators such as cylinders and hydraulic motors. Manufactured via Investment Casting in AISI 4140 alloy steel, this component achieves the complex internal porting geometry and precise spool bore tolerances required for reliable hydraulic performance at pressures up to 350 bar.
Ningbo Ruican’s investment casting process produces near-net-shape valve bodies with minimal machining allowance, reducing material waste and machining time compared to forged or bar-stock alternatives. Our 5-axis CNC MACHINING centers then achieve spool bore tolerances of IT6, with surface roughness of Ra 0.4 μm, ensuring leak-free operation and smooth spool movement throughout the valve’s service life.
Technical Specifications
| Parameter | Specification |
|---|---|
| Product Name | Hydraulic Directional Control Valve Body |
| Material | AISI 4140 Alloy Steel (42CrMo4 / SCM440 equivalent) |
| Manufacturing Process | Investment Casting (Lost Wax) |
| Weight Range | 2–40 kg |
| Working Pressure | Up to 350 bar (5,000 psi) |
| Tensile Strength | ≥ 930 MPa (quenched and tempered) |
| Yield Strength | ≥ 785 MPa |
| Hardness | 28–34 HRC |
| Spool Bore Tolerance | IT6, Ra 0.4 μm |
| Dimensional Tolerance | ISO 8062 CT5–CT6 |
| Pressure Testing | 100% pneumatic leak test at 1.5× working pressure |
| Surface Treatment | Zinc plating, black oxide, or phosphating |
Key Features
- Complex Internal Porting: Investment casting accurately forms intricate oil galleries and cross-drilled passages
- Precision Spool Bores: CNC honed to IT6 tolerance with Ra 0.4 μm surface finish for zero-leak sealing
- High-Pressure Rating: AISI 4140 heat treated to 28–34 HRC withstands sustained 350 bar operation
- 100% Leak Tested: Every valve body pressure tested before shipment
Quality Assurance
- Spectrometer chemical analysis on every heat
- Hardness testing on production samples
- CMM dimensional verification of critical spool bores
- Cleanliness inspection per ISO 4406 hydraulic cleanliness standards
- IATF 16949 certified manufacturing
Applications
Hydraulic systems for excavators, loaders, cranes, agricultural tractors, forestry equipment, and industrial hydraulic power units.
Why Choose Ningbo Ruican?
- Near-net-shape casting reduces machining cost up to 40% vs. bar stock
- Integrated casting + CNC machining under one roof
- PPAP documentation available for automotive customers
- Prototype to mass production (100 to 50,000+ pieces annually)
