Product Overview
The VT-DFPE-C-22/G24K0/2AOV/V is a direct-operated proportional directional control valve from Bosch Rexroth’s VT-DFP series, designed as a pilot control valve with electrical position feedback for SY(H)DFE electro-hydraulic control systems. Built on the 2X component series, it features an integrated analog control electronics unit (OBE) that eliminates the need for external amplifier cards, substantially simplifying control cabinet wiring.
What distinguishes the VT-DFPE-C-22/G24K0/2AOV/V is its spool configuration: the “C” designation indicates a 4-groove spool design specifically optimized for HFC water-based hydraulic fluids and other low-viscosity media. Compared with the standard A-type spool, the 4-groove architecture delivers superior contamination tolerance and flow stability in low-viscosity media, making it suitable for industrial applications demanding high media compatibility and long-term reliability.
The valve mounts via subplate according to ISO 4401 at nominal size NG6 (Cetop 3), with maximum operating pressure of 400 bar at ports A and P and 100 bar permitted at return port T. Every unit undergoes 100% simulation-based testing prior to shipment, covering null stability, flow linearity, and dynamic response. As a drop-in replacement, it is fully compatible with the OEM Rexroth specification in mounting interface, electrical connection, and performance characteristics.
Technical Specifications
All parameters below are verified against Bosch Rexroth official datasheet RE 29016 (Edition 2019-09) and corroborated by authorized supplier technical pages:
Complete Model: VT-DFPE-C-22/G24K0/2AOV/V
Material Number (MNR): R900705156
Brand: Bosch Rexroth
Product Series: VT-DFP series, component series 2X
Product Type: Direct-operated proportional directional valve with electrical position feedback, pilot control valve for SY(H)DFE systems
Control Electronics: Integrated analog (VT-DFPE type)
Spool Variant: C — 4-groove spool (suitable for HFC fluids)
Nominal Size: NG6 (Cetop 3 / ISO 4401)
Mounting: Subplate mounting
Max Operating Pressure (Ports A, P): 400 bar
Max Operating Pressure (Port T): 100 bar
Rated Flow: 22 L/min (at 150 bar pressure differential)
Supply Voltage: 24 V DC (model code ‘G24’)
Command Signal: ±10 V DC or 4–20 mA
Rated Current: 0.6 A
Ambient Temperature Range: 0 °C to +60 °C
Hydraulic Fluid Temperature Range: -20 °C to +70 °C
Viscosity Range: 20 – 380 mm²/s
Hydraulic Fluid: Mineral oil (HL, HLP per DIN 51524); HFC water-based fluids
Seal Material: FKM (model code ‘V’)
Protection Class: IP65
Electrical Connection: K0 standard industrial connector
Cleanliness Requirement: ISO 4406 18/16/13 or better
Weight: 2.25 kg
Note: Specifications are based on Bosch Rexroth official datasheet RE 29016 (Edition 2019-09) and verified supplier technical pages. Model code breakdown: VT-DFPE = pilot proportional valve with integrated analog electronics; C = 4-groove spool; 22 = 2X series; G24 = 24 V DC supply; K0 = connector configuration; 2AOV = spool adjustment and damping configuration; V = FKM seals.
Key Technical Advantages
1. Integrated Analog Electronics (OBE) — No External Amplifier Required
The VT-DFPE series integrates the analog control circuit board directly onto the valve body, eliminating the external amplifier card required in conventional configurations. System integrators no longer need a separate VT 5041-3X or equivalent external control module per valve. Control cabinet wiring is significantly simplified, and troubleshooting is reduced from a two-node “valve + amplifier” diagnostic path to a single-node check. For standardized production line design and long-term maintenance, this integration directly reduces total cost of ownership.
2. C-Type 4-Groove Spool Optimized for HFC Hydraulic Fluids
The “C” designation denotes a 4-groove spool architecture specifically engineered for HFC (water-glycol based) hydraulic fluids and other low-viscosity, high-water-content media. HFC fluids exhibit far lower lubricity than mineral oil, placing greater tribological demands on spool performance. The 4-groove design optimizes flow area distribution and pressure balancing to suppress spool sticking and hydraulic locking under low-viscosity conditions, while reducing the probability of contaminant particle accumulation at the metering edges.
3. Closed-Loop Control via Electrical Position Feedback (LVDT)
The valve employs a proportional solenoid with electrical position feedback (LVDT) in a closed-loop control architecture. Actual spool displacement is continuously measured by an integrated displacement sensor and fed back to the onboard analog electronics, which compares it against the command signal and applies dynamic correction. Compared with open-loop proportional valves without position feedback, the closed-loop architecture maintains spool positioning accuracy independent of fluid temperature variation, pressure fluctuation, and long-term wear, achieving control accuracy within ±3%.
4. High Pressure Rating with Broad Media Compatibility
Maximum operating pressure at ports A and P reaches 400 bar, with port T rated at 100 bar, allowing direct integration into high-pressure hydraulic circuits without additional pressure-reducing stages. Combined with FKM seals and the 4-groove spool design, the valve accommodates both mineral oil (HL, HLP) and HFC water-based fluids, with seal materials offering excellent resistance across multiple hydraulic media.
5. Wet-Sealed Proportional Solenoid and Precision-Lapped Spool Assembly
The proportional solenoid uses a wet-sealed construction with the coil isolated from hydraulic fluid, preventing coil corrosion and insulation degradation during extended service. The spool and sleeve are manufactured from high-strength alloy steel through multiple precision lapping operations, with clearance tolerances held to stringent specifications to minimize internal static leakage. Symmetrical return springs at both spool ends automatically return the spool to the center position upon power loss or zero command signal, providing fail-safe protection.
Application Areas
Injection Molding Machines: Closed-loop control of injection pressure and velocity for consistent part quality and improved production efficiency
Die Casting Equipment: Dynamic hydraulic pressure regulation for optimized cycle times; the 4-groove spool design is particularly suited to the high-frequency pressure cycling characteristic of die casting
Variable Pump Control Systems: Pilot valve for SY(H)DFEE electro-hydraulic control systems, enabling precise pump output flow and pressure regulation
Industrial Automation Lines: Integration with PLC and servo systems for complex force/position hybrid control processes
Material Testing Systems: Flow and pressure closed-loop control for electro-hydraulic servo loading systems, including high-frequency dynamic loading applications
HFC Fluid Applications: Metallurgical, mining, and other operations using water-glycol hydraulic fluids, where the 4-groove spool design ensures long-term stable operation
Expert Maintenance Tips
Pre-Installation Checks:
Verify the manifold mounting surface conforms to ISO 4401 NG6: surface roughness Ra ≤ 0.8 μm
Flush all piping with clean hydraulic fluid prior to installation; ensure system cleanliness reaches ISO 4406 18/16/13 or better
Inspect FKM seals for damage and confirm compatibility with the hydraulic fluid in use
Tighten mounting bolts in diagonal sequence to specified torque
Operational Maintenance:
Use a 5–10 μm precision pressure filter, specified without bypass and equipped with a contamination indicator
For mineral oil operation, ISO VG 46 is recommended; for HFC fluid service, maintain system cleanliness at an elevated standard
Maintain operating viscosity within 20 – 380 mm²/s
Periodically inspect the integrated electronics LED status indicators; confirm 24 V DC supply remains within the allowable range (withstands -5%/+40% variation)
System return pressure must not exceed 100 bar; back-pressure monitoring in the return line is recommended
Troubleshooting Guide:
Spool fails to actuate: Check 24 V DC supply, measure solenoid coil resistance, verify command signal (±10 V / 4–20 mA) reaches the valve correctly
Null-point drift: After ruling out fluid contamination, inspect return springs for fatigue and verify displacement sensor feedback signal integrity
Slow response: Check system cleanliness level; verify the 4-groove spool metering slots are not partially blocked by contaminant particles
Abnormal noise under HFC fluid operation: Confirm hydraulic fluid concentration and cleanliness meet HFC system requirements; check that return port pressure does not exceed the 100 bar limit
