CWGG-LGN Sun Hydraulics Counterbalance Valve 350 Bar

Product Overview

The CWGG-LGN (along with CWCG and CKIB series) is a screw-in cartridge load control / counterbalance valve engineered for high-pressure load holding, overrunning load control, and emergency lock protection in hydraulic systems. Manufactured to strictly match standard Sun Hydraulics T-17A cavities, this cartridge serves as a 100% direct drop-in replacement without requiring manifold modifications. Constructed with high-strength hardened alloy steel and Sun-style floating architecture, every valve undergoes 100% factory dynamic simulation testing under 350 bar operating pressure to guarantee zero internal leakage, exceptional durability, and smooth dynamic stability under severe working environments.

Technical Specifications 

• Model Codes: CWGG-LGN (Featured series includes CWCG-LGN, CKIB-XCN)

• Standard Cavity: Sun Cavity T-17A

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

• Maximum Operating Pressure: 350 bar (5000 psi)

• Peak Proof Pressure: 420 bar (6090 psi)

• Pilot Ratio: 2:1

• Pressure Setting Range: Range G: 70 – 280 bar (1000 – 4000 psi), standard setting 210 bar (3000 psi)

• Internal Leakage Rate: ≤ 5 drops/min at 85% of set pressure

• Adjustment Mechanism: L-Control (Standard Hex Socket Screw Adjustment)

• Seal Material: Option N (Buna-N Nitrile standard, Viton/FKM optional)

• Fluid Operating Temperature: -40°C to +100°C (-40°F to +212°F)

• Recommended Installation Torque: 200 – 215 Nm (150 – 160 lbf·ft)

• Unit Net Weight: Approx. 0.64 kg (1.41 lbs)

Key Technical Advantages

• 100% Direct Drop-in Interchangeability: Standardized external dimensions, threads, and performance curves allow immediate replacement of original Sun Hydraulics valves without redesigning manifolds.

• Floating Construction Technology: Features floating style construction that isolates moving valve components from external torque stress or cavity machining imperfections, eliminating internal spool binding.

• Vacuum Hardened Steel & Micro-Lapping: Critical internal seats and poppets are heat-treated and micro-ground to precise tolerances, providing extreme resistance to erosion and zero pressure drift during load retention.

• 100% Dynamic Factory Inspection: Every single valve is dynamically bench-tested at 350 bar operating pressure to verify pilot ratio response, cracking pressure, and zero-leakage retention before dispatch.

Application Areas

• Mobile Construction Machinery: Boom lift cylinders, winch motor load holding, and outrigger lock circuits on mobile cranes and excavators.

• Aerial Platforms & Elevating Work Equipment: Boom lift motion control and emergency lock protection on scissor lifts and telescopic booms.

• Industrial Pressing & Tooling Machines: Clamping pressure retention, mold locking manifolds, and gravity-fall prevention circuits in hydraulic presses.

Expert Maintenance Tips

• Fluid Cleanliness Protocol: Maintain system oil cleanliness to ISO 4406 standard 18/16/13 or cleaner, utilizing 10-micron filtration to protect micro-lapped seating surfaces.

• Calibrated Torque Installation: Tighten T-17A cavity cartridges strictly to 200–215 Nm (150–160 lbf·ft) using a calibrated torque wrench to avoid thread strain or cartridge sleeve distortion.

• O-Ring Seal Protection: Inspect manifold cavity chamfers for burrs before insertion. Pre-lubricate all external O-rings and backup rings with clean hydraulic fluid to prevent seal shearing during assembly.