loading
| Availability: | |
|---|---|
| Quantity: | |
LKF-60
MDP Hydraulics
This valve adopts an integrated design of "flow regulation + pressure compensation". Essentially, it achieves dynamic maintenance of a constant pressure difference between the inlet and outlet of the throttling port through the series connection of a built-in differential pressure reducing valve and an adjustable flow valve. When the inlet pressure or load pressure of the system changes, the compensating valve core will automatically adjust the opening degree of the pressure reducing port according to the equilibrium of the forces at both ends - when the load pressure increases, the valve core moves to the right to increase the pressure reducing port, reducing pressure loss; when the load pressure decreases, the valve core moves to the left to reduce the pressure reducing port, increasing the inlet pressure, ultimately ensuring that the set flow rate is not affected by pressure fluctuations and remains stable and constant. The flow regulation is achieved by rotating the valve stem to change the area of the throttling hole, with intuitive operation and a continuous adjustment range.
Flow range: 0~60L/min (0~16gpm), covering the flow control requirements of medium-sized and large hydraulic systems;
Nominal pressure: 210bar, the maximum pressure resistance is suitable for the pressure levels of mainstream industrial and construction machinery hydraulic systems;
Oil port specification: 1/2″-NPT threaded interface, in line with international universal installation standards, with reliable sealing performance;
Safety protection: Integrated with an adjustable spring safety ball valve, the factory preset pressure is 1500psi, the adjustment range is 750~3000psi, which can be flexibly set according to the system requirements to prevent overpressure damage;
Compatible media and environment: Compatible with common hydraulic media such as hydraulic oil, water - ethylene glycol, etc. The working temperature range is - 30℃ to + 110℃, capable of withstanding temperature fluctuations and impurity influences in harsh working conditions.
The pressure compensation mechanism completely eliminates the interference of load changes on the flow. Compared with ordinary throttling valves, the flow stability is significantly improved, ensuring the uniform and precise movement of the actuator (hydraulic cylinder / motor);
When combined with a variable pump, it can achieve power matching, reducing energy loss from overflow, and compared with traditional fixed throttling valves, the energy-saving effect is obvious;
The valve core adopts a precise fitting process, with a gap of ≤ 5μm, strong anti-pollution ability, and combined with high-quality sealing components, it extends the service life and reduces maintenance frequency;
As a direct supply product from a Chinese manufacturer, it ensures the core performance is comparable to international similar products, and has a significant price advantage, reducing the overall system procurement cost.
This valve features "pressure adaptation, stable flow, and durability in various working conditions", and is widely applicable to both industrial and mobile machinery scenarios. It is particularly suitable for hydraulic circuits that require high precision in flow control and system stability:
feed systems of CNC machines and machining centers, ensuring uniform tool feed speed and enhancing processing accuracy;
hydraulic circuits of injection molding machines and extruders, stabilizing melt injection and mold opening speeds to ensure product consistency in molding;
actuator speed control of hydraulic presses and bending machines, achieving smooth operation under heavy-load conditions;
hydraulic lubrication systems in steel mills and fluid transportation circuits in petrochemicals, suitable for high-pressure and wide-temperature working environments.
control of the boom, arm, and slewing mechanism of excavators, maintaining stable speeds of all actuators during compound movements;
lifting and slewing mechanisms of truck cranes and loaders, ensuring smooth and safe heavy-load lifting processes;
hydraulic lifting systems of dump trucks and drive circuits of port handling equipment, capable of withstanding bumpy road conditions and frequent start-stop operations;
suspension and drive systems of large tractors for farm implements, adapting to complex load changes in the field.
Mining machinery, paper-making equipment, port machinery, etc., require resistance to pressure fluctuations, tolerance to dust and oil contamination, as well as complex hydraulic systems with multiple actuators working together.
For different flow rates and installation requirements, MDP Hydraulics has launched the LKF series of full-range products to meet the diverse system adaptations:
Oil port size 3/8″-NPT, flow range 0~30L/min (0~8gpm), suitable for small hydraulic systems;
Main model, oil port size 1/2″-NPT, flow 0~60L/min (0~16gpm), covering medium and large systems;
Oil port size 3/4″-NPT, flow 0~114L/min (0~30gpm), suitable for high-flow hydraulic circuits (such as large hydraulic machines, port cranes).
Compatible Components: Can be seamlessly integrated with variable pumps, proportional valves, pressure reducing valves, hydraulic filters, etc., forming a complete flow-pressure control circuit to enhance the overall system efficiency;
Installation Assistance: Provides compatible seals, installation brackets and connectors, supporting both internal pilot and external pilot oil supply methods, meeting different system layout requirements;
Maintenance Accessories: Equipped with dedicated filter element kits and sealing component kits, facilitating later maintenance and replacement, prolonging the valve service life.
Select based on system working pressure, rated flow rate, medium type and interface specifications to ensure valve parameters match system requirements;
Ensure the cleanliness of the oil meets ISO 4406 ≤18/16/13 standards during installation to avoid impurities causing valve core jamming;
The safety pressure setting should be slightly higher than the system's maximum working pressure. Flow adjustment can be gradually calibrated by rotating the valve stem to ensure smooth system operation;
Regularly check the cleanliness of the oil and valve leakage, and replace the filter and sealing components every 6 to 12 months according to the working conditions.
As a direct supplier, MDP Hydraulics provides one-stop services such as product technical parameter consultation, selection guidance, installation and commissioning suggestions, supporting batch purchasing customization and after-sales warranty to ensure stable operation of the product and quick response.
A1: This is an advanced proportional flow control valve. Its "full-range pressure compensation" feature means that regardless of fluctuations in the inlet pressure (from the pump) and the outlet pressure (determined by the load), it can automatically adjust the opening degree of the internal throttle to ensure that the flow passing through the valve remains strictly constant at the set value. In the lifting system, its core role is to ensure that the lifting speed of the load (such as the hook, working platform) is completely independent of the load weight and fluctuations in pump pressure, achieving smooth, precise, and controllable movement. This is the foundation of safe and accurate operations.
A2: The fundamental difference lies in the ability to withstand changes in load:
• Ordinary throttle valve: The flow rate is greatly affected by the pressure difference between the inlet and outlet. When the load becomes heavier, the ascent speed will slow down; when the load becomes lighter, the descent speed will increase, making it impossible to achieve stable control.
• Standard speed control valve (with pressure compensation): It can usually only compensate for changes in the inlet pressure, but has limited ability to compensate for changes in the outlet pressure (load pressure).
• Full-range pressure-compensated flow control valve: It can simultaneously compensate for fluctuations in both the inlet and outlet pressures. Regardless of how the load changes or how the output pressure of the pump fluctuates, it can lock the flow at the set value, providing the highest level of speed stability.
A3: During the descent process of the lifting system, the load gravity becomes the driving force, which is likely to cause uncontrollable and excessive descent, which is extremely dangerous. When this valve is installed on the return oil line during the descent:
1. Achieves controllable descent: By setting a precise flow rate, it is possible to strictly limit the return oil flow, thereby controlling the descent speed.
2. Overcomes the "weightlessness" effect: As the load descends, the load pressure decreases. Ordinary valves would cause the descent to speed up the more it falls. However, the pressure compensation function can immediately respond to this pressure change, maintaining a constant throttling effect and ensuring a uniform, smooth, and impact-free descent.
A4: This is a crucial safety design. In a typical lifting system loop:
• Explosion-proof valve/balance valve: Installed directly at the interface of the actuator (hydraulic cylinder/motor), its main function is to lock and prevent the load from falling in case of pipeline rupture, providing passive safety.
• This flow control valve: is usually connected in series after the explosion-proof valve, and is located on the return oil path between the main control valve and the oil tank. Its function is to actively and precisely regulate the descent speed.
The two work together: when the flow rate increases, the flow valve does not play a major role; when the flow rate decreases, after the pilot pressure opens the explosion-proof valve, the oil must pass through the precise throttling of this valve to return to the oil tank, thereby achieving precise speed control under a safe condition.
A5: The selection must be based on accurate system parameters:
1. Maximum system flow rate: Calculated based on the size of the cylinder or motor and the required maximum lifting speed.
2. Working pressure range: The rated pressure of the valve must cover the maximum working pressure of the system. Special attention should be paid to the maximum return oil back pressure that may occur during descent.
3. Control mode: Choose manual adjustment type (with a handwheel) or electric proportional control type (remote and stepless speed adjustment through analog signals). Electric proportional type is more suitable for automated control.
4. Installation interface: Match the existing pipe or valve block interfaces (such as thread, flange specifications).
• Installation direction: The installation must strictly follow the arrow indicating the oil flow direction marked on the valve body. It is usually installed on the return oil path of the actuating element.
• Filter requirements: The valve incorporates a precision throttling edge and a pressure compensation valve core. Extremely high cleanliness of the oil is required (typically recommended as NAS 1638 grade 7 or higher), and a high-pressure filter must be installed before the valve.
• Oil discharge pipeline: If it is an external oil discharge type (Y port), a separate oil pipe must be used to directly connect back to the oil tank, and zero back pressure must be maintained. Otherwise, the compensation function will fail.
• Debugging: When adjusting for the first time, start by gradually increasing the flow setting value from a lower level and observe the load movement. Avoid increasing the speed too rapidly.
Q7: The regulated flow of the valve is unstable or fluctuates. What could be the reasons?
1. Oil contamination: Tiny particles get stuck in the pressure compensation valve core or the throttle port, causing it to frequently move, which is the most common reason. Check and replace the filter element.
2. Air in the system: The compressibility of air causes fluctuations in flow and pressure. Ex排气 at the high point of the system.
3. Back pressure in the oil discharge path： The external oil discharge pipe is flattened or clogged， resulting in abnormal pressure in the control chamber of the compensation valve core.
4. Wear of the valve itself： After long-term use， the throttle port or the compensation valve core becomes worn， leading to a decrease in control accuracy.
A8: This requires a combination of the valve's function and the control system:
• Electric proportional control type: Through PLC or controller, the control current (voltage) input can be controlled by a ramp signal, allowing the valve's opening degree to increase or decrease gradually, thereby achieving a smooth change in flow rate, enabling the actuator to accelerate and decelerate smoothly, achieving the effect of "soft start/soft stop", and significantly reducing shock.
A9: Yes, and it is a common configuration in high-performance enhancement systems. The electro-hydraulic proportional flow valve acts as the actuator of the system, receiving command signals from the controller. The encoder continuously monitors the position or speed of the load and feeds back to the controller. The controller compares the set value with the feedback value and dynamically adjusts the current signal sent to the flow valve through algorithms such as PID to form a closed-loop control, thereby achieving extremely high precision in position retention, synchronous movement, or speed tracking.
A10: These are crucial technical documents. You can obtain them in the following ways:
1. Contact the supplier: Request the specific model's detailed product samples from the technical support department of the product supplier or manufacturer, which include all performance curves and mechanical installation drawings.
2. Official website: Search for and download the technical documents (usually in PDF format) on the manufacturer's official website.
3. Provide the model: Make sure you can provide the complete model and serial number on the valve body label to obtain the most accurate matching information.
