EFBG-10-500-C-20T49 | YUKEN Proportional Flow Control Valve 500L/min

Product Overview

The EFBG-10-500-C-20T49 is a classic model in the YUKEN EFBG series of proportional electro-hydraulic flow control and relief valves. This valve is an energy-saving meter-in type flow control valve that integrates flow control and pressure control (relief function) in a single unit, supplying only the minimum pressure and flow necessary for actuator drive.

The core design philosophy of the EFBG series is demand-based energy supply: the valve controls pump pressure by following the load pressure while keeping the differential pressure minimized—maintaining pump-side pressure only 0.9 MPa (9 kgf/cm²) above the load pressure. This characteristic significantly reduces overflow losses and system heat generation, achieving substantial energy savings. Additionally, the valve incorporates a temperature compensation function, ensuring stable flow control regardless of fluid temperature variations.

The EFBG-10-500-C-20T49 features 10 size (NG25 / CETOP D10) , maximum metered flow of 500 L/min, C-type proportional pilot relief valve (pressure adjustment range 1.5–15.7 MPa), and 20T49 design series. The valve must be used with a dedicated YUKEN proportional amplifier.

Model Code Breakdown (EFBG-10-500-C-20T49):

• EFB: Electro-Hydraulic Proportional Flow Control and Relief Valve

• G: Subplate Mounting

• 10: Valve size 10 (NG25 / CETOP D10)

• 500: Maximum metered flow 500 L/min

• C: Proportional pilot relief valve pressure grade — C-type (range 1.5–15.7 MPa)

• 20T49: Design/configuration code (20T = main design, 49 = minor variation; mounting dimensions unchanged)

Technical Specifications (Bulleted List)

• Model: EFBG-10-500-C-20T49

• Brand: YUKEN

• Series: EFBG Series

• Product Type: Proportional Electro-Hydraulic Flow Control and Relief Valve

• Mounting Type: Subplate Mounting

• Mounting Standard: CETOP D10 / NG25

• Maximum Operating Pressure: 24.5 MPa (250 kgf/cm² / 3550 PSI) 

• Maximum Flow: 500 L/min

• Metered Flow Adjustment Range: 5–500 L/min

• Minimum Pilot Pressure: 1.5 MPa

• Pilot Flow: Steady 1 L/min / Transition 6 L/min

• Differential Pressure: 0.9 MPa (9 kgf/cm²) 

• Flow Hysteresis: ≤3%

• Flow Repeatability: ≤1%

• Pressure Adjustment Range (C-type): 1.5–15.7 MPa

• Pressure Hysteresis: ≤3%

• Pressure Repeatability: ≤1%

• Flow Control Rated Current: 900 mA

• Pressure Control Rated Current: 800 mA (C-type)

• Coil Resistance: 10 Ω

• Supply Voltage: 24V DC

• Medium: ISO VG32–68 hydraulic oil

• Operating Temperature: -20°C to +80°C

• Temperature Compensation: Built-in

• Mass: Approx. 60 kg

Key Technical Advantages

1. Energy-Saving Meter-In Design — Significant Power Reduction

The EFBG-10-500-C-20T49 is an energy-saving meter-in type flow control valve that supplies only the minimum pressure and flow necessary for actuator drive. The valve maintains pump-side pressure only 0.9 MPa (9 kgf/cm²) above the load pressure. This characteristic significantly reduces overflow losses, minimizes system heat generation and power consumption—particularly suitable for long-running high-flow hydraulic systems.

2. Dual Proportional Flow and Pressure Control

The EFBG-10-500-C-20T49 integrates flow control and pressure control (relief function) in a single valve, with two independent electrical signals controlling flow and pressure respectively. As a “flow-pressure composite proportional valve,” it enables precise stepless speed regulation of actuators while simultaneously providing system pressure setting and overload protection. One valve replaces what traditionally required two valves, significantly simplifying hydraulic system layout.

3. Built-in Temperature Compensation — Stable Flow Regardless of Oil Temperature

The valve incorporates a built-in temperature compensation function, ensuring stable flow control regardless of fluid temperature variations. This ensures consistent actuator speed across varying operating temperatures, improving machining precision and operational stability.

4. High Precision with Low Hysteresis

Flow hysteresis ≤3% with repeatability ≤±1%; pressure hysteresis ≤3% with repeatability ≤±1%. Ensures high precision and repeatability in actuator speed and system pressure control, meeting the stringent requirements of injection molding machines, die-casting machines, and other precision equipment.

5. C-Type Wide Pressure Adjustment Range for Flexible Application

C-type pressure adjustment range covers 1.5–15.7 MPa (15–157 kgf/cm²) . From low-pressure precision control to medium-high pressure heavy-duty applications, the valve adapts flexibly. The series also offers H-type (1.5–24.5 MPa) pressure grades for diverse system requirements.

6. 500 L/min Ultra-High Flow Capacity

The EFBG-10-500-C-20T49 delivers 500 L/min maximum flow capacity in an NG25 package. The metered flow adjustment range covers 5–500 L/min. In high-flow hydraulic systems, it provides precise and stable flow and pressure control.

7. International Standard Compliance with High Installation Compatibility

Mounting conforms to CETOP D10 (NG25) standards. Fully compatible with globally adopted NG25 size interfaces for direct replacement of same-series, same-specification products. Must be used with a dedicated YUKEN proportional amplifier. Response time ＜20 ms.

Application Areas

• Large Injection Molding Machinery — High-flow composite proportional control of injection speed and holding pressure

• Large Die-Casting Machines — Precise proportional regulation of injection speed and pressure

• Heavy Hydraulic Presses and Forging Equipment — Stepless adjustment of slide speed and working pressure

• Metallurgical Equipment — High-flow speed and pressure composite control for rolling mill hydraulic systems

• Marine Hydraulic Systems — High-flow energy-saving control for deck machinery

• Heavy Construction Machinery — High-flow proportional control for travel and working equipment

• Test Benches and Servo Hydraulic Systems — High-precision control for dynamic loading and simulation

Expert Maintenance Tips

1. Installation Guidelines

• EFBG-10-500-C-20T49 is subplate mounting — mounting surface must conform to CETOP D10 (NG25) standards.

• Vertical installation is recommended to ensure spool movement is not affected by gravity.

• Thoroughly clean the mounting surface and all ports (P, A, B, T) before installation to prevent foreign particles from entering and causing spool sticking or seal damage.

• The independent large-diameter drain port must be routed separately back to the tank to avoid return line interference.

2. Electrical Requirements

• A dedicated YUKEN proportional amplifier is mandatory! PLC direct voltage output cannot drive the proportional solenoid—current amplification is required.

• Power supply: 24V DC.

• Control signals: 0–10V / 4–20mA.

• Flow control rated current: 900 mA, pressure control rated current: 800 mA (C-type).

• Coil resistance: 10 Ω.

3. Hydraulic Fluid Management

• Recommended cleanliness: NAS Class 7 or better, recommended 10 μm filtration.

• Working medium: ISO VG32–68 hydraulic oil.

• Operating temperature: -20°C to +80°C.

• Minimum pilot pressure: 1.5 MPa.

4. Pressure Setting and Adjustment

• C-type pressure adjustment range: 1.5–15.7 MPa (15–157 kgf/cm²) .

• Pressure adjustment is performed via the proportional pilot relief valve—adjust gradually under system operating conditions.

• Factory-preset; refer to YUKEN technical documentation for adjustments.

5. Periodic Maintenance and Troubleshooting

• Inspect the valve body for external oil leakage every 2,000 operating hours or at least annually.

• Check electrical connectors for looseness, oxidation, or moisture ingress.

• If flow instability or pressure fluctuation occurs: First check fluid cleanliness and pilot screens for blockage.

• If slow response or reduced control precision occurs: Check proportional amplifier parameter settings and solenoid coil resistance.

• High contamination resistance: Key components feature special surface treatment with cycle life exceeding 10 million cycles.