Hydraulic control valve for function actuation

A hydraulic control valve is used in hydraulic systems to trigger specific actions and functions. There are automatic and manual control valves. Control valves are generally self-returning.

Hydraulic systems with controllable actuators

A hydraulic system consists of a pump, lines, and actuators that trigger a specific function. Typical actuators are linear motors or hydraulic cylinders, or radial motors. However, a change in pressure or a diversion of the volumetric flow can also result in additional functions. A typical example is triggering pressure valves, closing flaps, etc.

The control valve is used to divert the volumetric flow in a targeted manner and route it to a specific point in the hydraulic system.

Hydraulic control valve: design

A hydraulic control valve consists of a hydraulic block with an internal spool or rotary shut-off element, as well as an external actuator. In manual control valves, this actuator is designed as a lever.

Electromechanical control valves use a spool or a servo motor for this purpose. Both can be integrated easily into a control system of any complexity. From local push-button actuation to remote control via the Internet, all functional options are available today.

The complexity and functional scope of control valves are available in a wide range. The spectrum ranges from simple on/off valves to multi-acting control modules that can direct a volumetric flow in very different directions.

A distinction is made between single-acting and multi-acting control valves. Double-acting control valves are particularly widespread. They can be combined into control blocks of any length, enabling a correspondingly wide range of functions in the hydraulic system.

Hydraulic control valve: applications

Control valves are found in virtually all hydraulic systems in which certain areas are to be addressed only in a targeted manner. The commonly used double-acting valves can trigger a function and, through a counter-movement, retract it again. Manually controlled hydraulic cylinders are generally operated in this way: pushing the control lever forward extends the cylinder; pulling it back retracts it again. When the lever is released, an internal spring returns the lever to the center and blocks the volumetric flow.

Control valves are often used, for example, in construction machinery. The operation of excavators, tracked vehicles, or dumpers is generally carried out with the aid of control valves. Here, 4-way valves are frequently used due to their compact design and wide functional scope.

In addition to forward and backward movement, these valves also enable hydraulic actuators to be controlled via a lateral movement. Furthermore, 4-way valves can trigger two functions simultaneously through diagonal actuation. The 4-way valves in construction vehicles are often supplemented by electrical push-buttons and switches. This provides the operator with a particularly wide range of functions without having to take their hands off the control levers.