Chapter 5 Hydraulic Control Valves 1.In structure,all hydraulic control valves consist of the valve body,the valve core(spool,cone or ball)and the operating elements used to control the valve core. The three basic types of cores are shown in Fig.5-1. 2.In operating principle,the orifice flow formula should be kept true for the orifice size,the pressure differences between the inlet and outlet and the flow rate of through the valves. Homepage List Upwards Downwards Retum Exit Chapter 5 Hydraulic Control Valves 4 1. In structure, all hydraulic control valves consist of the valve body, the valve core (spool, cone or ball) and the operating elements used to control the valve core. The three basic types of cores are shown in Fig.5-1. 2. In operating principle, the orifice flow formula should be kept true for the orifice size, the pressure differences between the inlet and outlet and the flow rate of through the valves