A high-pressure control valve
The pressure control device shown in FIG. has a high-pressure control valve, shown diagrammatically, with an adjusting drive. In the chromatography of supercritical flow media, the high-pressure control valve serves as a counter pressure control valve which keeps under specific, predeterminable pressure conditions a separating column that is connected upstream, on the pressure side. Water Control valves At the inlet side of the high-pressure control valve is a pressure-measuring transducer which is connected to an electronic control means. The control means is in turn connected to the adjusting drive of the high-pressure control valve, thus producing a closed control loop. The high-pressure control valve has a high-pressure-supply line and a low-pressure side with a transition to atmospheric pressure. Depending on the position of the high-pressure control valve, a corresponding "pile-up pressure" is produced at its high-pressure side, where the packed column (not shown) is also located. The working pressures in that case may be several hundred bar, for example up to 800 bar.
shows more clearly the structure of the high-pressure control valve.Water Power Control Valves It includes a valve housing having an inlet channel connected to the high-pressure-supply line, and an outlet channel in the form of a capillary. The outlet channel is located within a small capillary tube , the inlet end of which forms a valve seat which cooperates with a valve body. WATER POWER CONTROL VALVEThe valve body is adjustable in accordance with the double arrow Pf with the aid of the adjusting drive shown in FIG. The valve body has on its face opposed to the valve seat a sealing disc which comes into contact with the valve seat when the valve is closed. The sealing disc may be made of brightly polished metal, but is preferably made of Teflon? (polytetrafluoroethylene PTFE).
MORE NEWS
2011-12-07