FDBA-LAN RDDA-LAN CKGB-XCN PBDB-LBN CXDA-XCN Sun Hydraulics Cartridge Valve 350 bar

Product Overview

This product range covers five major series of Sun Hydraulics screw-in cartridge valves, all globally recognized high-performance hydraulic components. Sun Hydraulics is renowned for its Floating Style Construction and standardized cavity system, where all cartridge valves within the same cavity size are physically and functionally interchangeable.

Product type attribution is as follows:

• FDBA-LAN: Pressure-compensated flow control valve with reverse flow check, Cavity T-13A, Capacity 23 L/min

• RDDA-LAN: Direct-acting relief valve, Cavity T-10A, Capacity 95 L/min

• CKGB-XCN: Pilot-to-open check valve, Cavity T-17A, Capacity 240 L/min

• PBDB-LBN: Pilot-operated pressure reducing valve, Cavity T-11A, Capacity 40 L/min

• CXDA-XCN: Free flow check valve, Cavity T-13A, Capacity 80 L/min

Our complete range of Sun Hydraulics cartridge valves strictly adheres to OEM technical standards, achieving 100% direct interchangeability with original components. Every unit undergoes 100% simulated operating condition bench testing prior to shipment, ensuring performance parameters are fully consistent with genuine Sun Hydraulics products. Direct replacement significantly reduces equipment downtime and maintenance costs.

Technical Specifications 

FDBA-LAN (Pressure-Compensated Flow Control Valve)

• Product Series: Sun Hydraulics FDBA series pressure-compensated flow control valve

• Model Code: FDBA-LAN

• Brand: Sun Hydraulics

• Product Type: Pressure-compensated flow control valve with reverse flow check

• Cavity: T-13A

• Series: 1

• Maximum Flow Capacity: 23 L/min (6 gpm)

• Maximum Operating Pressure: 350 bar (5000 psi)

• Adjustment – Turns from Closed to Open: 5 CCW turns

• Minimum Leakage at Shut-Off: 0.4 L/min

• Valve Hex Size: 22.2 mm (7/8 in)

• Valve Installation Torque: 41 – 47 Nm (30 – 35 lbf·ft)

• Adjustment Screw Internal Hex Size: 4 mm

• Locknut Torque: 9 – 10 Nm

• Weight: Approx. 0.14 kg

• Seal Kits: Buna: 990010007; EPDM: 990010014; Viton: 990010006

RDDA-LAN (Direct-Acting Relief Valve)

• Product Series: Sun Hydraulics RDDA series direct-acting relief valve

• Model Code: RDDA-LAN

• Brand: Sun Hydraulics

• Product Type: Direct-acting relief valve

• Cavity: T-10A

• Series: 1

• Maximum Flow Capacity: 95 L/min (25 gpm)

• Maximum Operating Pressure: 350 bar (5000 psi)

• Factory Pressure Setting: 15 L/min (4 gpm)

• Maximum Leakage at Reseat: 10 drops/min (0.7 cc/min)

• Response Time – Typical: 2 ms

• Reseat: ≥ 90% of cracking pressure

• Adjustment – Turns from Min. to Max.: 6 CW turns

• Valve Hex Size: 22.2 mm (7/8 in)

• Valve Installation Torque: 41 – 47 Nm (30 – 35 lbf·ft)

• Adjustment Screw Internal Hex Size: 4 mm

• Locknut Torque: 9 – 10 Nm

• Weight: Approx. 0.17 kg

• Seal Kits: Buna: 990310007; EPDM: 990310014; Viton: 990310006

CKGB-XCN (Pilot-to-Open Check Valve)

• Product Series: Sun Hydraulics CKGB series pilot-to-open check valve

• Model Code: CKGB-XCN

• Brand: Sun Hydraulics

• Product Type: Pilot-to-open check valve

• Cavity: T-17A

• Series: 3

• Maximum Flow Capacity: 240 L/min (60 gpm)

• Maximum Operating Pressure: 350 bar (5000 psi)

• Pilot Ratio: 3:1

• Maximum Leakage: 1 drop/min (0.07 cc/min)

• Valve Hex Size: 31.75 mm (1 1/4 in)

• Valve Installation Torque: 203 – 217 Nm (150 – 160 lbf·ft)

PBDB-LBN (Pilot-Operated Pressure Reducing Valve)

• Product Series: Sun Hydraulics PBDB series pilot-operated pressure reducing valve

• Model Code: PBDB-LBN

• Brand: Sun Hydraulics

• Product Type: Pilot-operated pressure reducing valve

• Cavity: T-11A

• Series: 1

• Maximum Flow Capacity: 40 L/min (10 gpm)

• Maximum Operating Pressure: 350 bar (5000 psi)

• Pressure Adjustment Range: 3.5 – 105 bar

• Control Pilot Flow: 0.11 – 0.16 L/min

• Adjustment – Turns from Min. to Max.: 5 CW turns

• Valve Hex Size: 22.2 mm (7/8 in)

• Valve Installation Torque: 41 – 47 Nm (30 – 35 lbf·ft)

CXDA-XCN (Free Flow Check Valve)

• Product Series: Sun Hydraulics CXDA series free flow check valve

• Model Code: CXDA-XCN

• Brand: Sun Hydraulics

• Product Type: Free flow check valve

• Cavity: T-13A

• Series: 1

• Maximum Flow Capacity: 80 L/min (20 gpm)

• Maximum Operating Pressure: 350 bar (5000 psi)

• Maximum Leakage at 110 SUS (24 cSt): 1 drop/min (0.07 cc/min)

• Valve Hex Size: 22.2 mm (7/8 in)

• Valve Installation Torque: 41 – 47 Nm (30 – 35 lbf·ft)

• Weight: Approx. 0.10 kg

• Seal Kits: Buna: 990010007; EPDM: 990010014; Viton: 990010006

Key Technical Advantages

1. Sun Hydraulics Standardized Cavity Design – 100% Interchangeability

All models utilize Sun Hydraulics standard cavity designs—FDBA-LAN and CXDA-XCN use T-13A cavity, RDDA-LAN uses T-10A cavity, CKGB-XCN uses T-17A cavity, and PBDB-LBN uses T-11A cavity. All cartridge valves within the same cavity size are physically and functionally interchangeable. This standardization ensures 100% direct interchangeability without any manifold modification or system adjustment.

2. Sun Floating Style Construction – Reduced Binding Risk

All products incorporate Sun Hydraulics’ patented floating style construction. This design significantly reduces the risk of internal parts binding due to excessive installation torque or cavity/cartridge machining variations, enhancing installation reliability and service life.

3. Direct-Acting Relief Valve – Fast Response & Essentially Zero Leakage (RDDA-LAN)

RDDA-LAN is a direct-acting relief valve with normally closed design, featuring typical response time of only 2 ms. The valve operates smoothly and quietly with essentially zero leakage, with leakage at reseat not exceeding 10 drops/min (0.7 cc/min). The spool/poppet is manufactured from hardened, precision ground steel for long-term wear resistance.

4. Pilot-to-Open Check Valve – 3:1 Pilot Ratio & Extremely Low Leakage (CKGB-XCN)

CKGB-XCN is a pilot-to-open check valve with a 3:1 pilot ratio. Featuring a non-sealed pilot design, it offers maximum leakage of only 1 drop/min (0.07 cc/min) . Suitable for load holding and isolation circuits requiring pilot-operated opening.

5. Pilot-Operated Reducing Valve – Excellent Pressure/Flow Characteristics (PBDB-LBN)

PBDB-LBN is a pilot-operated pressure reducing valve featuring exceptionally flat pressure/flow characteristics, very stable operation, and low hysteresis. A 150 micron stainless steel screen protects the main stage orifice from contamination. Pressure adjustment range 3.5–105 bar.

6. Flow Control Valve – Sharp-Edged Orifice Design for Viscosity Compensation (FDBA-LAN)

FDBA-LAN is a pressure-compensated flow control valve offering infinite adjustment from nearly closed to maximum flow. The sharp-edged orifice design minimizes the effects of viscosity variation on flow. The balanced adjustment mechanism ensures easy adjustment even under high pressure.

7. Free Flow Check Valve – Extremely Low Leakage (CXDA-XCN)

CXDA-XCN is a free flow check valve allowing free flow from inlet (port 1) to outlet (port 2) while blocking reverse flow. Maximum leakage is only 1 drop/min (0.07 cc/min) .

8. 100% Simulated Operating Condition Testing

Every unit undergoes 100% simulated operating condition bench testing prior to shipment, ensuring consistent, stable performance at rated pressure and flow.

Application Areas

• FDBA-LAN (Pressure-Compensated Flow Control Valve) :

  • Inlet or outlet metering circuits

  • Applications requiring pressure-compensated flow control

  • Actuator speed control circuits

• RDDA-LAN (Direct-Acting Relief Valve) :

  • Hydraulic system overload protection and pressure limiting

  • Cross-port relief circuits

  • Load holding applications

• CKGB-XCN (Pilot-to-Open Check Valve) :

  • Load holding and isolation circuits

  • Accumulator isolation and charging control

  • Hydraulic cylinder position locking

• PBDB-LBN (Pilot-Operated Pressure Reducing Valve) :

  • Multi-pressure sub-circuit systems

  • Hydraulic systems requiring constant secondary pressure

  • Single pump multi-pressure control applications

• CXDA-XCN (Free Flow Check Valve) :

  • Hydraulic system isolation and check applications

  • Pump outlet protection and bypass control

Expert Maintenance Tips

1. Verify Model and Cavity Compatibility Prior to Installation

All models are screw-in cartridge valves. Confirm that the manifold cavity matches the valve:

• FDBA-LAN requires T-13A cavity

• RDDA-LAN requires T-10A cavity

• CKGB-XCN requires T-17A cavity

• PBDB-LBN requires T-11A cavity

• CXDA-XCN requires T-13A cavity

Different cavity sizes are not interchangeable.

2. Correct Installation Torque

Recommended installation torque for each model:

• FDBA-LAN: 41 – 47 Nm (30 – 35 lbf·ft)

• RDDA-LAN: 41 – 47 Nm (30 – 35 lbf·ft)

• CKGB-XCN: 203 – 217 Nm (150 – 160 lbf·ft)

• PBDB-LBN: 41 – 47 Nm (30 – 35 lbf·ft)

• CXDA-XCN: 41 – 47 Nm (30 – 35 lbf·ft)

Use a torque wrench for precise torque control—never exceed the specified value. While Sun’s floating style construction reduces binding risk, over-torquing can still cause body distortion or seal failure.

3. Seal Material Selection

All products offer multiple seal options:

• Buna-N (Nitrile) : Standard configuration, suitable for mineral-based hydraulic oils

• Viton (Fluorocarbon) : Suitable for high temperatures and various hydraulic fluids

• EPDM: For phosphate ester fluids only—exposure to petroleum-based hydraulic oils or lubricating greases will damage the seals

4. Pressure Setting Precautions (RDDA-LAN)

RDDA-LAN relief valves have adjuster screw seals exposed to system pressure—system pressure must be relieved before making adjustments. Correct procedure: check current setting → relieve system pressure → adjust valve → re-pressurize and verify new setting. For optimal repeatability, select a spring range where the desired relief setting falls in the mid-to-high range of the spring’s capabilities.

5. Back Pressure Effects

• Back pressure at the tank port (port 2) of RDDA-LAN relief valves directly adds to the valve setting at a 1:1 ratio

• Pressure at port 3 of PBDB-LBN reducing valves is directly additive to the valve setting at a 1:1 ratio and should not exceed 350 bar

6. System Cleanliness Management

Although Sun Hydraulics products offer excellent contamination tolerance, recommended system cleanliness is ISO 4406 Code 18/16/13 or better. PBDB-LBN pilot-operated valves have tighter internal clearances and require higher cleanliness levels.

7. Periodic Functional Checks

Perform functional checks every 2,000 operating hours or annually:

• FDBA-LAN: Verify flow control accuracy and pressure compensation function

• RDDA-LAN: Verify cracking pressure accuracy and leakage within specification

• CKGB-XCN: Verify pilot-open function and leakage

• PBDB-LBN: Verify reduced pressure stability

• CXDA-XCN: Verify check function in both directions

If abnormalities are observed, arrange for servicing or replacement.