Sun Series Hydraulic Cartridge Valve Replacement | CACA CBCA CBGA RDDA RDHA

The Sun Series High-Precision Threaded Cartridge Valves by Chengyuan Hydraulic—featuring CACA-LHN, CBCA-LHN, CBGA-LHN load-holding counterbalance valves, and RDDA-LSV, RDHA-CAN direct-acting relief valves—are premium, heavy-duty fluid control components engineered for 100% direct drop-in interchangeability with original Sun Hydraulics products. Manufactured to rigorous global engineering tolerances, these cartridge valves precisely match the OEM cavity specifications, pitch threads, and volumetric flow curves. This enables B2B buyers and fleet managers to replace components seamlessly inside existing manifold blocks without experiencing custom re-machining delays.

As the central control elements in high-pressure sub-circuits, the counterbalance family ensures ultra-smooth motion control and zero-drift load holding, while the direct-acting relief family provides instant over-pressure spike protection. To eliminate any structural stick-slip or internal leakage risks under severe field conditions, every single valve manufactured by Chengyuan is subjected to 100% simulated working condition testing prior to shipment. This process ensures impeccable P-Q characteristics and absolute stability, offering a cost-effective, premium alternative for mobile and industrial hydraulic systems worldwide.

Technical Specifications

Load-Holding Counterbalance Valve Series:

• CACA-LHN:

  • Functional Type: 3-port counterbalance valve (standard load control)

  • Cavity Specification: T-11A

  • Pilot Ratio: 4:1

  • Maximum Rated Flow Rate: 60 L/min

  • Control Mechanism: L (Standard screw adjustment with water-tight cap)

  • Pressure Setting Range: H (1000 – 4000 psi / 70 – 280 bar, standard setting 280 bar)

  • Sealing Compound: N (Buna-N / Nitrile seals)

• CBCA-LHN:

  • Functional Type: 3-port counterbalance valve (low pilot ratio for enhanced stability and anti-shudder control)

  • Cavity Specification: T-11A

  • Pilot Ratio: 3:1

  • Maximum Rated Flow Rate: 60 L/min

  • Control & Range Parameters: L control / H range (70 – 280 bar) / N seals

• CBGA-LHN:

  • Functional Type: High-capacity 3-port counterbalance valve

  • Cavity Specification: T-2A

  • Pilot Ratio: 4.5:1

  • Maximum Rated Flow Rate: 120 L/min

  • Control & Range Parameters: L control / H range (70 – 280 bar) / N seals

Direct-Acting Relief Valve Series:

• RDDA-LSV:

  • Functional Type: 2-port direct-acting relief valve (low leakage, high contamination tolerance)

  • Cavity Specification: T-10A

  • Maximum Rated Flow Rate: 95 L/min

  • Control Mechanism: L (Standard screw adjustment)

  • Pressure Setting Range: S (25 – 1500 psi / 1.7 – 105 bar, for low-to-medium sub-circuit protection)

  • Sealing Compound: V (FKM / Viton seals for high-temperature fluid compatibility)

• RDHA-CAN:

  • Functional Type: High-capacity 2-port direct-acting relief valve

  • Cavity Specification: T-3A

  • Maximum Rated Flow Rate: 200 L/min

  • Control Mechanism: C (Tamper-resistant / non-adjustable factory-preset cap)

  • Pressure Setting Range: A (100 – 3000 psi / 7 – 210 bar)

  • Sealing Compound: N (Buna-N / Nitrile seals)

• Maximum Continuous Operating Pressure: 350 bar (5000 psi)

Key Technical Advantages

• Innovative “Floating Style” Mechanical Engineering: Incorporating the classic floating spool architecture, an intentional micron-level radial clearance separates the internal moving components from the external threaded shell. If a manifold cavity suffers from minor thermal distortion or excessive installation over-torque, the internal spool self-aligns perfectly, completely eliminating torque-induced spool binding.

• Ultra-Low Internal Leakage via Hardened Metallurgy: The internal spools and sleeves are machined from high-grade bearing steel and processed through specialized vacuum heat treatment to exceed 60 HRC hardness. The mating surfaces undergo mirror-lapping and optical polishing, restricting the static internal leakage of the CACA/CBCA series below 5 drops/minute at 200 bar, ensuring secure boom locking without mechanical drift.

• Optimized Flow Paths & Minimal Control Hysteresis: The internal structural geometries are hydrodynamically engineered to minimize fluid restriction and shear heating at high velocities. The core spring-guide seats of the RDDA/RDHA relief valves are cross-calibrated against side-tilt, yielding responsive cracking metrics with control hysteresis under 3% to prevent high-frequency circuit resonance or squealing.

• 100% Dynamic Simulation Benchmarks: Deviating from basic batch inspection routines, Chengyuan runs a complete dynamic cycle scan for pressure-drop characteristics, cracking thresholds, and millisecond-level pilot response on every cartridge. This testing verifies that the performance curves of each model code align flawlessly with the host machine’s original control logic.

Application Areas

This versatile series serves as an immediate premium replacement integrated into customized manifold blocks and critical multi-port control nodes:

• Mobile & Lifting Machinery: Luffing and winch control counterbalance blocks for truck cranes and crawler cranes (CACA/CBGA); outrigger lock systems for truck-mounted cranes and aerial work platforms.

• Construction & Excavation Equipment: Auxiliary hydraulic breaker attachment relief protection for excavators (RDHA); primary quick-coupler and attachment steering manifests for wheel loaders.

• Industrial Automation Systems: Primary safety relief manifolds inside heavy metallurgical hydraulic power units (RDDA); integrated manifold blocks for hydraulic balers, recycling scrap shears, and injection molding machinery oil sources.

Expert Maintenance Tips

• Strict Adherence to Official Installation Torques: Although the floating architecture provides excellent tolerance against structural mechanical stresses, excessive torque can over-stretch threads and warp localized seals. Always employ a calibrated torque wrench: apply 40-45 Nm for T-11A cavities (CACA/CBCA) and 60-70 Nm for T-2A cavities. Never rely on unmeasured manual tightening.

• High-Standard Fluid Cleanliness Control: Due to the microscopic clearances within these cartridge assemblies, preserve system oil hygiene to match or exceed ISO 4406 19/15/11 (NAS Class 7). Silt particles lodged within tiny balance orifices will trigger mechanical drift or lockup; we recommend incorporating a 10-micron absolute return filtration matrix.

• Verify Cavity Concentricity and Perpendicularity: When cutting custom manifolds to replace OEM valves, ensure specialized form-tools match standard cavity geometry exactly. Concentricity errors between the multi-diameter steps of the cavity will distort the lower O-rings upon insertion, causing inter-chamber bypass leakage.