HAWE LHK Series Control Valve | LHK40F-11CPV-350 LHK44G-21-250 | Pressure Compensated Counterbalance Valve

The HAWE LHK Series provided by Chengyuan Hydraulic is a high-precision, pressure-compensated load-holding valve designed to control the descent of overrunning loads. Featuring models like LHK40F and LHK44G, this series prevents executive components from accelerating out of control. We prioritize technical authenticity, ensuring 100% original-place interchangeability with HAWE standards. At Chengyuan, every valve is subjected to 100% simulated condition testing, guaranteeing that the opening pressure and zero-leakage performance meet the rigorous safety demands of heavy-duty hydraulic systems.

Technical Specifications (Bulleted List)

• Model Code: LHK40F-11CPV-350, LHK 44 G-11-165, LHK 44 G-21-250/250

• Max Operating Pressure: $350\text{–}400\text{ bar (5076–5800 psi)}$

• Nominal Flow Rate: $60\text{–}100\text{ L/min}$ (LHK 40/44 series)

• Pilot Ratio: Standard $1:4.6$ (or specific as per code)

• Setting Pressure: Factory preset (e.g., $350\text{ bar}$ or $250\text{ bar}$)

• Connection Type: F (Pipe mounting) or G (Manifold mounting)

• Fluid Temperature: $-40\text{°C}$ to $+80\text{°C}$

• Unit Weight: Approximately $1.8\text{–}3.5\text{ kg}$

Key Technical Advantages

• Static Load Locking: As a zero-leakage valve, the LHK ensures absolute locking of the actuator in the neutral position, eliminating any “load drift” caused by internal hydraulic leakage.

• Pressure-Compensated Descent: The integrated pressure compensation ensures that the lowering speed depends solely on the spool stroke, regardless of load variations, resulting in smooth and vibration-free motion.

• Back-Pressure Independent Pilot: The pilot piston is engineered to remain unaffected by back-pressure in the return line, ensuring consistent and precise opening control in complex circuits.

• Integrated Relief Protection: Selected models include built-in relief functions to absorb pressure spikes caused by thermal expansion or external impact, protecting cylinder seals and hoses from damage.

Application Areas

• Cranes & Hoists: Winch motor control and boom cylinder load holding.

• Aerial Work Platforms: Boom extension protection and smooth retraction control.

• Drilling Rigs: Reliable load holding and precise lowering of mast cylinders.

Expert Maintenance Tips

• Pressure Setting Check: Before installation, ensure the valve’s crack pressure is set at least $1.3$ times higher than the maximum load pressure for reliable locking.

• Strict Filtration: Counterbalance valves are highly sensitive to contamination. Maintain system filtration at $10\text{ }\mu\text{m}$ or better to prevent spool sticking or leakage.

• Pilot Line Bleeding: During initial commissioning, cycle the actuator slowly to bleed air from the pilot lines. Trapped air is the primary cause of “shuddering” during the start of a descent.