Exploring the Different Types of Hydraulic Valves Used in Cranes and Bulldozers

Why Hydraulic Valves Matter in Construction Machinery

Hydraulic Valves are essential incontrolling the flow and pressure of hydraulic fluid within a system. Without these valves, managing the precise movements of crane booms, bulldozer blades, or other critical attachments would be nearly impossible. Valves allow for the safe and efficient operation of machinery by ensuring fluid reaches the right actuators at the right time and pressure.

In cranes and bulldozers, hydraulic valves contribute to:

• Lifting and lowering heavy loads

• Blade tilt and angle adjustments

• Boom extension/retraction

• Swing and rotation control

• Overload protection and safety management

Key Types of Hydraulic Valves Used in Cranes and Bulldozers

Let’s explore the main categories of hydraulic valves employed in these heavy machines:

1. Directional Control Valves

Function: These valves manage the path of hydraulic fluid in the system and determine which direction an actuator (cylinder or motor) will move.

Common Types:

• Spool Valves – Found in joystick control systems, they slide to open or block passages.

• Solenoid Valves – Electrically operated, providing quick and reliable directional switching.

• Pilot-Operated Valves – Used in larger systems to control heavy-duty actuators through a smaller pilot valve.

Applications in Cranes and Bulldozers:

• Controlling the up/down or in/out motion of crane booms.

• Steering bulldozer tracks or adjusting blade positions.

2. Pressure Relief Valves

Function: These valves protect the hydraulic system by releasing excess pressure when it exceeds safe limits.

Variants:

• Direct-Acting Relief Valves

• Pilot-Operated Relief Valves – Often used for smoother and more stable pressure regulation.

Applications:

• Preventing damage due to hydraulic overload during lifting operations.

• Safety fail-safes in bulldozer push/pull mechanics.

Why Longerfa’s Relief Valves Stand Out:
Ningbo Longerfa’s LF Series Pressure Relief Valves offer high flow capacity, compact design, and excellent stability, ensuring your equipment operates safely under varying loads.

3. Flow Control Valves

Function: These valves control the rate of flow in a hydraulic circuit, thus determining the speed of actuators.

Types:

• Needle Valves

• Throttle Valves

• Proportional Flow Valves

In Practice:

• Adjusting boom extension speed in cranes.

• Managing blade movement pace in bulldozers.

Precision flow control is essential for operator comfort and task accuracy, particularly during delicate operations.

4. Load Holding Valves (Counterbalance and Overcenter Valves)

Function: These valves prevent unwanted movement of loads when hydraulic pressure is lost or reduced. They are vital for systems lifting or suspending loads.

Key Features:

• Maintains position under load.

• Prevents "free-fall" or uncontrolled descent.

Applications:

• Cranes hoisting heavy objects.

• Bulldozer blades positioned mid-air during maneuvering.

Longerfa’s Advantage:
Our load-holding valves are designed with anti-cavitation features and precise pilot ratios, ensuring both safety and efficiency during operation.

5. Cartridge Valves

Function: Cartridge valves are modular valves inserted into standard cavities, offering flexibility, compact design, and easy maintenance.

Why They Matter:

• Space-saving in compact machinery systems.

• Easy to swap or upgrade without overhauling the entire hydraulic manifold.

• Provide custom control logic for complex machines.

Popular Uses:

• Custom hydraulic control blocks in crane and bulldozer systems.

• High-performance applications needing tailored valve logic.

Ningbo Longerfa’s Offering:
We specialize in high-performance screw-in cartridge valves, including relief, check, flow, and directional types. These valves are engineered to ISO and SAE standards, ensuring compatibility and reliability in OEM equipment.

Integrated Valve Solutions for OEMs and Dealers

At Ningbo Longerfa Hydraulic Co., Ltd., we go beyond standalone valve manufacturing. We offer:

• Custom hydraulic manifold design

• OEM valve system development

• Rapid prototyping for specialized valve logic

• ISO-certified quality assurance

Our valves are widely used in cranes, bulldozers, excavators, and other construction machinery both domestically and globally. By focusing on performance, durability, and cost-efficiency, we help our partners stay competitive in an increasingly demanding industry.

Trends in Hydraulic Valve Technology

As smart construction machinery and automation become more prevalent, hydraulic valves are evolving. Key trends include:

• Electro-hydraulic proportional control valves for smoother, more precise operation.

• Energy-saving valve systems that reduce fuel consumption.

• Modular and integrated solutions for faster assembly and easier maintenance.

Longerfa is actively investing in R&D to stay ahead of these trends and meet the future needs of our clients.

Final Thoughts

Choosing the right hydraulic valves is essential for ensuring your crane or bulldozer performs with precision, reliability, and safety. At Ningbo Longerfa Hydraulic Co., Ltd., we are proud to be a trusted supplier of high-quality hydraulic valves and cartridge valves to clients around the world.

Whether you're an OEM, equipment dealer, or procurement specialist looking for a reliable partner, we invite you to explore our product catalog or contact our team for tailored solutions.

Contact Us Today
📧 Email: ken@longerfa.com
🌐 Website: www.longerfavalves.com
📍 Address: Ningbo Longerfa Hydraulic Co., Ltd., No.18 Xingye East Road, Xiepu Town, Zhenhai District, Ningbo City, Zhejiang Province，China

Empowering heavy machinery with precision-engineered hydraulic solutions.