Logic valves are a type of hydraulic valves that are used to control flow, pressure, or direction in high-pressure, high-flow applications. They are also known as cartridge valves or poppet valves, because they consist of cartridge-type elements that make a full-beveled seat and prevent internal leakage. Logic valves are mounted in a manifold, which reduces the need for piping and increases the reliability and efficiency of the hydraulic system.
Types of Logic Valves
There are three main types of logic valves: directional, pressure, and flow control. Each type can be controlled by a smaller pilot valve, which can be either solenoid-operated or manually-operated. The pilot valve determines the opening and closing of the logic valve, which allows or blocks the flow of hydraulic fluid.
Directional Control Logic Valves
Directional control logic valves are used to change the direction of fluid flow in a hydraulic circuit. They can have two or more ports, depending on the number of flow paths required. For example, a two-port directional control logic valve can act as a simple on/off valve, while a three-port directional control logic valve can divert the flow to one of two outlets. Directional control logic valves can also be combined with flow control logic valves to achieve proportional control of flow and direction.
Pressure Control Logic Valves
Pressure control logic valves are used to regulate the pressure of fluid flow in a hydraulic circuit. They can act as relief valves, reducing valves, sequence valves, counterbalance valves, or unloading valves, depending on the application. Pressure control logic valves can also be combined with directional control logic valves to achieve load-sensing or pressure-compensated control of flow and pressure.
Flow Control Logic Valves
Flow control logic valves are used to adjust the flow rate of fluid flow in a hydraulic circuit. They can act as throttle valves, flow regulators, or flow dividers, depending on the application. Flow control logic valves can also be combined with pressure control logic valves to achieve constant flow or constant power control of flow and pressure.
Advantages of Logic Valves
Logic valves have several advantages over conventional hydraulic valves, such as:
- Higher performance: Logic valves can handle higher pressures, higher flow rates, higher speeds, and shockless shifting with low pressure drop. They also have faster response times and better accuracy, thanks to their poppet-type design and pilot control.
- Lower installation cost: Logic valves can be incorporated in manifold blocks, which reduces the need for piping, fittings, and adapters. This also saves space and weight, and simplifies the hydraulic system design.
- Higher reliability: Logic valves have less internal leakage and less risk of contamination, thanks to their poppet-type design and manifold mounting. They also have less vibration and noise, and less maintenance requirements, thanks to their fewer moving parts and simpler construction.
Logic valves are a type of hydraulic valves that are used to control flow, pressure, or direction in high-pressure, high-flow applications. They are also known as cartridge valves or poppet valves, because they consist of cartridge-type elements that make a full-beveled seat and prevent internal leakage. Logic valves are mounted in a manifold, which reduces the need for piping and increases the reliability and efficiency of the hydraulic system. Logic valves can be classified into three main types: directional, pressure, and flow control. Each type can be controlled by a smaller pilot valve, which can be either solenoid-operated or manually-operated. Logic valves have several advantages over conventional hydraulic valves, such as higher performance, lower installation cost, and higher reliability.