Chapter 5 Hydraulic Control Valves 5.1 Introduction The types of control valves used today are too numerous to be mentioned.Most valves,however,perform three primary functions in the hydraulic system:to control the oil pressure (pressure control valves),the flow rate(flow control valves)and the direction of oil flow(directional control valves)in the system to ensure the actuators in proper working on order the load requested. 5.1.1 Basic characteristics Although there are many types of hydraulic control valves and they might be quite different from each other in either the functions or configurations,there exist basic characteristics. Homepage List Upwards Downward达 Return ExitChapter 5 Hydraulic Control Valves 3 5.1 Introduction 5.1.1 Basic characteristics The types of control valves used today are too numerous to be mentioned. Most valves, however, perform three primary functionsin the hydraulic system: to control the oil pressure (pressure control valves), the flow rate (flow control valves) and the direction of oil flow (directional control valves) in the system to ensure the actuators in proper working on order the load requested. Although there are many types of hydraulic control valves and they might be quite different from each other in either the functions or configurations, there exist basic characteristics