EFBG-06-250-C-1720 EFBG-06-250A-C-20T145 Yuken Flow Control Valve 245 bar

Product Overview

The EFBG series electro-hydraulic proportional flow control valves are power-saving proportional flow control valves engineered by Yuken for industrial hydraulic systems, integrating a proportional solenoid flow control valve with a proportional pilot relief valve for independent electrical control of flow and pressure via two separate command signals.

The EFBG series is a power-saving valve that supplies only the minimum pressure and flow necessary for actuator drive. The valve maintains pump pressure at only a small differential pressure (approx. 0.7–0.9 MPa) above the load pressure, significantly reducing energy consumption and oil temperature rise. An integrated temperature compensation function ensures consistent flow control regardless of fluid temperature variations.

The EFBG series covers EFBG-03 (NG6) and EFBG-06 (NG10) sizes, with maximum flow capacities of 250 L/min and 500 L/min respectively. The High Flow Series doubles flow capacity compared to conventional models, allowing smaller valve sizes to achieve the same flow requirements. EFBG-06-250-C-1720 features maximum metered flow of 250 L/min; EFBG-06-250A-C-20T145 with “A” designation indicates LVDT spool position closed-loop feedback.

⚠️ Product Function Note:

• The EFBG series is a meter-in power-saving valve that controls pump pressure through load feedback, supplying only the minimum pressure and flow required by the actuator.

• The series integrates a proportional pilot relief valve for simultaneous proportional flow control and proportional pressure control via two independent electrical signals.

⚠️ Model Code Decoding (using EFBG-06-250-C-1720 as example) :

• EFB = Electro-Hydraulic Proportional Flow Control Valve

• G = Subplate Mounting

• 06 = Valve size (06 = NG10)

• 250 = Maximum metered flow (250 L/min)

• C = Pilot relief valve pressure range (C = 1.4–15.7 MPa; H = 1.4–24.5 MPa)

• 1720 = Design/configuration code

Model Code Decoding (using EFBG-06-250A-C-20T145 as example) :

• A = With LVDT spool position feedback (closed-loop control version)

• 20T145 = Specific configuration code

Technical Specifications 

EFBG-06-250-C-1720 (Standard Type)

• Product Series: Yuken EFBG series electro-hydraulic proportional flow control valve

• Model Code: EFBG-06-250-C-1720

• Brand: Yuken

• Product Type: Electro-hydraulic proportional flow control valve (with proportional pilot relief valve)

• Valve Size: 06 (NG10)

• Mounting Type: Subplate mounting

• Maximum Operating Pressure: 24.5 MPa (245 bar)

• Maximum Flow: 250 L/min

• Metered Flow Adjustment Range: 2.5 – 250 L/min

• Minimum Pilot Pressure: 1.5 MPa

• Pilot Flow (Steady State) : 1 L/min

• Pilot Flow (Transition) : 4 L/min

• Flow Control Rated Current: 750 mA

• Flow Control Coil Resistance: 10 Ω

• Control Differential Pressure: 0.7 MPa

• Flow Control Hysteresis: ≤ 3%

• Flow Control Repeatability: ≤ 1%

• Pressure Control (C-type) Adjustment Range: 1.4 – 15.7 MPa

• Pressure Control (C-type) Rated Current: 820 mA

• Pressure Control Coil Resistance: 10 Ω

• Pressure Control Hysteresis: ≤ 3%

• Pressure Control Repeatability: ≤ 1%

• Compatible Hydraulic Fluids: Mineral-based hydraulic oils (ISO VG 32-68)

• Temperature Compensation: Built-in

• Mounting Interface Standard: ISO 4401 (NG10)

• Mass: Refer to Yuken technical manual

EFBG-06-250A-C-20T145 (Closed-Loop Feedback Type)

• Product Series: Yuken EFBG series electro-hydraulic proportional flow control valve

• Model Code: EFBG-06-250A-C-20T145

• Brand: Yuken

• Product Type: Electro-hydraulic proportional flow control valve (with LVDT spool position closed-loop feedback)

• Valve Size: 06 (NG10)

• Mounting Type: Subplate mounting

• Maximum Operating Pressure: 24.5 MPa (245 bar)

• Maximum Flow: 250 L/min

• Metered Flow Adjustment Range: 2.5 – 250 L/min

• Feedback Type: LVDT spool position feedback

• Dynamic Error: ≤ 0.5%

• Minimum Pilot Pressure: 1.5 MPa

• Control Differential Pressure: 0.7 MPa

• Flow Control Repeatability: ≤ 1%

• Mounting Interface Standard: ISO 4401 (NG10)

EFBG-03 Series (Reference Specifications, NG6 Size)

• Valve Size: 03 (NG6)

• Maximum Operating Pressure: 24.5 MPa (245 bar)

• Maximum Flow: 125 L/min

• Metered Flow Adjustment Range: 1 – 125 L/min

• Minimum Pilot Pressure: 1.5 MPa

• Pilot Flow (Steady State) : 1 L/min

• Pilot Flow (Transition) : 3 L/min

• Flow Control Rated Current: 800 mA

• Control Differential Pressure: 0.7 MPa

• Pressure Control (C-type) Adjustment Range: 1.4 – 15.7 MPa

• Pressure Control (C-type) Rated Current: 890 mA

Key Technical Advantages

1. Power-Saving Design for Significant Energy Reduction

The EFBG series is a power-saving proportional valve. Its core advantage lies in load-pressure feedback control of pump pressure, maintaining pump pressure at only 0.7–0.9 MPa differential pressure above the load. This design ensures the system supplies only the pressure and flow required by the actuator, dramatically reducing overflow losses and achieving 30%+ energy savings while effectively suppressing oil temperature rise.

2. Dual Proportional Independent Control – Decoupled Pressure and Flow Regulation

The EFBG series integrates a proportional flow control valve and a proportional pilot relief valve in a single unit, with two independent electrical signals for separate flow and pressure control. Flow and pressure controls operate independently without mutual interference, enabling decoupled precise adjustment of pressure and flow to meet multi-mode operating requirements. Pressure adjustment ranges: C-type 1.4–15.7 MPa, H-type 1.4–24.5 MPa.

3. Built-in Temperature Compensation for Stable Flow Across Full Temperature Range

The EFBG series features integrated temperature compensation for stable flow control regardless of oil temperature variations. Combined with pressure compensation, flow output remains unaffected by both load pressure fluctuations and oil temperature changes, with flow repeatability ≤ 1%.

4. High Flow Series – Smaller Size, Higher Capacity

The High Flow Series increases maximum flow capacity by 100% —03 size from 125 L/min to 250 L/min, 06 size from 250 L/min to 500 L/min. For the same flow requirements, a smaller valve size can be selected, effectively reducing system footprint, weight, and piping complexity.

5. Optional LVDT Closed-Loop Feedback for Ultra-High Control Precision

EFBG-06-250A-C-20T145 features LVDT spool position feedback for closed-loop control with dynamic error ≤ 0.5% . Real-time spool position feedback to the controller enables true closed-loop precision control, meeting the stringent requirements of high-precision hydraulic systems.

6. 100% Direct Interchangeability and Simulated Condition Testing

All models strictly adhere to Yuken original mounting dimensions and interface standards (ISO 4401), enabling direct drop-in replacement of original valves without manifold modification or system adjustment. Every unit undergoes 100% simulated operating condition bench testing prior to shipment, ensuring consistent, stable performance at rated pressure and flow.

Application Areas

• Large Injection Molding Machines: Proportional flow and pressure control for clamping, injection, and holding systems

• Die-Casting Machines: Precise flow and pressure control for injection systems

• Heavy Machine Tools: Table feed and pressure control for hydraulic systems

• Construction Machinery: Flow distribution and pressure regulation for travel and working attachments

• Metallurgical Equipment: Precise flow and pressure control for rolling mill hydraulic systems

• Marine Hydraulic Systems: High-precision flow and pressure control for deck machinery and steering gear

• Test Benches and Servo Hydraulic Systems: Dynamic loading and precision simulation control

Expert Maintenance Tips

1. Verify Model and System Compatibility Prior to Installation

The EFBG series offers 03 (NG6) and 06 (NG10) sizes with C/H pressure ranges. Confirm prior to installation:

• Valve size meets system flow requirements (03=125 L/min, 06=250 L/min)

• Pressure adjustment range (C-type 1.4–15.7 MPa / H-type 1.4–24.5 MPa) covers system operating pressure

• Control signal type matches the controller (0–10V / 4–20mA / PWM)

2. Pilot Pressure and Pilot Oil Circuit

The EFBG series requires minimum pilot pressure of 1.5 MPa. Pilot oil supply pressure must not fall below this value under any operating condition, or the valve will fail to function properly. The pilot oil circuit should be supplied separately from the pump outlet or a dedicated pilot oil source to avoid main circuit pressure fluctuations.

3. Dedicated Drain Line Return

The EFBG series is equipped with an independent large-port drain line that must be routed directly back to the tank—do not connect in parallel with the return line. Excessive drain line back pressure will affect pilot stage performance and degrade control accuracy.

4. System Cleanliness Management

The EFBG series is a precision proportional valve demanding high oil cleanliness. Recommended system cleanliness: NAS 1638 Class 7 or higher, with filtration rating ≤10μm high-precision filters in the system return line.

5. Electrical Connection and Command Signals

• EFBG series uses DC24V proportional solenoid power supply

• Command signals are typically 0–10V or 4–20mA—verify controller output signal type matches valve specifications prior to wiring

• Models with LVDT feedback (e.g., EFBG-06-250A-C-20T145) require feedback signal wiring

6. Commissioning and Parameter Setting

• During commissioning, start from low command signals and gradually increase, monitoring system flow/pressure response for smooth operation

• Flow and pressure are two independently controlled parameters—set and tune separately

• Yuken recommended proportional amplifiers (e.g., AMN-D-10 series) are recommended for optimal performance

7. Periodic Functional Checks

Perform functional checks every 2,000 operating hours or annually: verify linearity between command signal and flow/pressure, response time testing, and leakage inspection. If reduced control accuracy, sluggish response, or abnormal leakage is observed, arrange for servicing or replacement.