Pressure Control Valves 
Press control valves are used for controlling the pressure in a hydraulic system and protect its hydraulic pump and actuators from over-load. According to their functions, they can be divided into different types such as relief valxe, sequence valve and unloading relief valve.

Pressure-control valves are used in almost every hydraulic system. Hydraulic pressure contol valves help in a wide variety of functions, right from keeping system pressures below a desired upper limit to maintaining a set pressure in the entire hydraulic system. Pressure control valves are used to control and regulate pressure in fluid power systems. In hydraulic systems pressure control valves are used to unload the system and to maintain and regulate pressure at the desired values. There are different types of hydraulic pressure control valves which are normally closed valves, except for one or two, which are normally open. For most of these pressure control valves, a restriction is needed to produce the required pressure control.