Cartridge Valves & Manifold Valves
Cartridge valves, also known as two-way cartridge valves, logic valves, or poppet valves, are innovative hydraulic control components featuring a two-way check element as their main body, utilizing pilot control and cartridge-style connections. These valves offer numerous advantages in various hydraulic systems, including those integrated with a hydraulic gearbox.
The hydraulic gearbox often relies on the precision control provided by cartridge valves to achieve efficient power transmission. Cartridge valves feature small spool mass, short travel, rapid action, sensitive response, compact structure, good manufacturability, reliable operation, long service life, and facilitate pipeless connections and integrated control. They are particularly suitable for high-pressure, large-flow systems, making them ideal for integration with a hydraulic gearbox in demanding applications.
Cartridge valve control technology is widely used in forging machinery, plastic machinery, metallurgical machinery, casting machinery, ships, mines, and other engineering fields, often working in conjunction with a hydraulic gearbox to optimize system performance.
I. Basic Structure and Working Principle of Cartridge Valves
The main structure of a two-way cartridge valve includes the cartridge assembly, control cover plate, pilot control, and manifold block, as shown in Figure 5-59a, with Figure 5-59b showing its schematic symbol. This configuration allows for seamless integration with various hydraulic components, including the hydraulic gearbox, to create efficient hydraulic systems.
Figure 5-59: Cartridge valve structure diagram (a) and schematic symbol (b)
1-Cartridge assembly 2-Control cover plate 3-Pilot control valve 4-Manifold block
1. Cartridge Assembly
The cartridge assembly consists of a valve spool, valve body, spring, and seals, and can be either a poppet valve structure or a spool valve structure. This critical component works harmoniously with the hydraulic gearbox to regulate fluid flow precisely. As the main body of the cartridge valve, the cartridge element is a hollow cylinder with a conical sealing surface at the front.
Cartridge valves with different performances have different spool structures. For example, the conical end of the cartridge valve spool can be a blocked conical surface, or a conical surface with a damping hole or an open triangular groove. This versatility makes them suitable for various applications, including those involving a hydraulic gearbox.
The cartridge element is installed in the cartridge block and can move axially freely. Controlling the opening and closing of the cartridge valve spool and the size of the opening can control the flow direction, pressure, and flow rate of the fluid in the main oil circuit, which is essential for optimizing the performance of a hydraulic gearbox.
Figure 5-60: Common cartridge assembly structures and graphic symbols
1-Valve spool 2-Valve sleeve 3-Spring
In systems incorporating a hydraulic gearbox, the cartridge assembly's design becomes even more critical, as it must handle the varying pressure and flow demands generated by the gearbox during operation. The ability to precisely control these parameters ensures the hydraulic gearbox operates at peak efficiency while maintaining system stability.
2. Control Cover Plate
The control cover plate consists of various miniature pilot control elements (such as valves, check valves, plug-in pressure regulating valves, etc.) and other components embedded in the cover plate. These elements work in tandem with the pilot control valve to regulate the cartridge assembly's operation, which in turn affects the performance of any connected hydraulic gearbox.
Sensors and other devices for detecting the working status of the cartridge assembly can also be installed on the control cover plate. This monitoring capability is crucial for maintaining optimal performance in systems that include a hydraulic gearbox, allowing for real-time adjustments and preventive maintenance.
Depending on the control function, control cover plates can be divided into three categories: direction control cover plates, pressure control cover plates, and flow control cover plates. When they have two or more functions, they are called composite control cover plates. Each type plays a specific role in regulating the hydraulic gearbox's operation.
The main functions of the control cover plate are to fix the cartridge assembly, connect the control oil circuit with the main valve control chamber, and provide a mounting surface for various control components. These functions are essential for integrating the cartridge valve with a hydraulic gearbox, ensuring seamless communication between components.
3. Pilot Control Valve
The pilot control valve refers to a small-diameter control valve installed on the control cover plate (or manifold block) to control the action of the cartridge assembly. These valves are critical for precise control in systems that include a hydraulic gearbox, allowing for fine-tuning of performance parameters.
They mainly include 6mm and 10mm diameter solenoid directional valves, solenoid ball valves, pressure valves, proportional valves, adjustable dampers, buffers, and hydraulic control pilot valves. These components work together to regulate the hydraulic gearbox's operation under varying load conditions.
When the main cartridge has a larger diameter, two-stage control with a smaller diameter cartridge can be used to improve its dynamic characteristics. This staged control approach is particularly beneficial in systems with a hydraulic gearbox, where load demands can vary significantly.
Pilot control elements are used to control the movement of the cartridge spool to realize various functions of the cartridge valve, which directly impact the performance of the hydraulic gearbox. By precisely regulating flow, pressure, and direction, these control elements ensure the hydraulic gearbox operates efficiently across its entire range of operation.
II. Manifold Valves
Manifold valves are the abbreviated form of stacked hydraulic valves. They are a new type of hydraulic component developed on the basis of manifold blocks, often used in conjunction with a hydraulic gearbox to create compact, efficient hydraulic systems.
The structural characteristic of manifold valves is that the valve body itself is both the body of the hydraulic valve and functions as a channel body and connector. This integrated design makes them ideal for use with a hydraulic gearbox, as it reduces space requirements and potential leak points.
Using manifold valves can realize pipeless integrated connection between hydraulic components, greatly simplifying the connection mode of the hydraulic system, making the system compact, reducing power consumption, and shortening the design and installation cycle. These advantages are particularly valuable in systems incorporating a hydraulic gearbox, where space and efficiency are often critical considerations.
Figure 5-61: Manifold valve assembly showing stacked configuration with integrated油路 channels
Currently, the production of manifold valves has formed a series: the position and diameter of the main oil circuit channels, and the size, position, and number of mounting screw holes of each diameter series of manifold valves are the same as those of the main directional valve of the corresponding diameter. This standardization allows for easy integration with various components, including a hydraulic gearbox, from different manufacturers.
Therefore, each diameter series of manifold valves can be stacked to form a corresponding hydraulic system. This modular approach simplifies system design when incorporating a hydraulic gearbox, as components can be easily added or removed based on specific application requirements.
In a stacked hydraulic system, a subsystem consisting of a main directional valve and other related control valves can be stacked into a valve group. The valve groups can be connected with a base plate or oil pipe to form a total hydraulic circuit. This flexibility is particularly advantageous when designing systems around a hydraulic gearbox, as it allows for customization based on specific performance requirements.
Therefore, when designing a hydraulic system, after completing the design of the system schematic diagram, it is also necessary to draw a manifold valve type hydraulic system diagram. For the convenience of design and selection, the currently produced manifold valves all provide their type spectrum symbols. Relevant departments have issued typical series type spectra of domestic ordinary manifold valves, ensuring compatibility with various system components including the hydraulic gearbox.
When paired with a hydraulic gearbox, manifold valves provide a compact, efficient solution for controlling the complex flow patterns required in modern hydraulic systems. Their modular design allows for easy maintenance and upgrades, ensuring the hydraulic gearbox can adapt to changing operational demands over time.
Classification of Manifold Valves
Manifold valves can be divided into two categories according to their working performance: single-function valves and composite function valves. Both types play important roles in systems that include a hydraulic gearbox, providing different levels of control complexity based on application requirements.
1. Single-Function Manifold Valves
Similar to ordinary hydraulic valves, single-function manifold valves also include pressure control valves (including relief valves, pressure reducing valves, sequence valves, etc.), flow valves (such as throttle valves, one-way throttle valves, speed control valves, etc.), and directional valves (such as directional valves, check valves, hydraulic control check valves, etc.). These valves work in conjunction with the hydraulic gearbox to regulate system parameters.
For easy connection to form a system, each valve body is equipped with more than four through channels: P, T, A, and B. The oil ports in the valve are respectively connected with their corresponding channels according to the function of the valve. This standardization allows for seamless integration with a hydraulic gearbox and other system components.
For easy stacking, the positions of the above channels are the same on the joint surface of the valve body. Due to structural limitations, most of these channels are specially shaped holes formed by precision casting, which allows for compact design while maintaining the flow rates required by the hydraulic gearbox.
2. Composite Function Manifold Valves
Composite function manifold valves combine multiple control functions into a single valve body, offering space-saving advantages in systems that include a hydraulic gearbox. These integrated valves reduce the number of connections required, minimizing pressure drops and potential leak points.
By incorporating multiple functions into one component, composite manifold valves simplify system design while maintaining the precise control required by a hydraulic gearbox. They can combine pressure, flow, and direction control in various configurations, providing tailored solutions for specific applications.
The use of composite function valves with a hydraulic gearbox can significantly reduce overall system complexity, improve response times, and enhance efficiency by minimizing fluid turbulence and pressure losses between separate components.
Applications in Industry
Both cartridge valves and manifold valves find extensive application across various industries, often working in conjunction with a hydraulic gearbox to provide reliable, efficient power transmission and control. Their robust design and precise control capabilities make them indispensable in modern hydraulic systems.
Manufacturing
In manufacturing equipment, these valves control presses, injection molding machines, and assembly lines, often paired with a hydraulic gearbox for precise speed and torque control.
Mobile Hydraulics
Construction and agricultural machinery rely on these valves, integrated with a hydraulic gearbox, to power complex movements while maintaining efficiency in varying conditions.
Marine & Offshore
Naval and offshore applications utilize these valves with a hydraulic gearbox for critical systems requiring reliability in harsh environments with extreme pressure variations.
The versatility of cartridge and manifold valves makes them suitable for integration with a hydraulic gearbox in almost any hydraulic system requiring precise control. From small-scale industrial machinery to large-scale construction equipment, these valves provide the reliability and performance needed to keep operations running smoothly.
When properly matched with a hydraulic gearbox, cartridge and manifold valves can significantly enhance system efficiency, reduce energy consumption, and extend equipment lifespan by providing precise control over pressure, flow, and direction. This synergy between components results in hydraulic systems that are more responsive, reliable, and cost-effective over their operational lifetime.
Technical Advantages
For Cartridge Valves
- Rapid response and precise control, ideal for integration with a hydraulic gearbox
- Compact design saves space in systems featuring a hydraulic gearbox
- High flow capacity suitable for large hydraulic gearbox applications
- Long service life reduces maintenance costs for hydraulic gearbox systems
- Easy to replace without extensive system disassembly, minimizing hydraulic gearbox downtime
For Manifold Valves
- Pipeless design reduces leak points in hydraulic gearbox systems
- Modular construction allows easy system expansion with additional hydraulic gearbox components
- Reduced installation time compared to traditional systems with a hydraulic gearbox
- Improved system efficiency by minimizing pressure drops between hydraulic gearbox components
- Easier maintenance access compared to complex piped systems with a hydraulic gearbox
The combination of cartridge valves, manifold valves, and a hydraulic gearbox represents a sophisticated approach to hydraulic system design, offering unparalleled efficiency, control, and reliability. These components work in harmony to provide precise fluid power management across a wide range of industrial applications.
As technology continues to advance, the integration of these components will become even more seamless, with smart monitoring and control systems enhancing the performance of both the valve assemblies and the hydraulic gearbox. This evolution will drive greater efficiency, reduced energy consumption, and improved reliability in hydraulic systems worldwide.
Whether designing a new system or upgrading an existing one, the careful selection and integration of cartridge valves, manifold valves, and a hydraulic gearbox will ensure optimal performance, longevity, and cost-effectiveness. Engineers and system designers should consider these components as fundamental building blocks for modern hydraulic systems.
Learn more