[Oxygen valve] Introduction - Riverstone oxygen valve shut-off valve in physical chemistry experiments, often use the oxygen, nitrogen, hydrogen, argon and other gases. These gases are generally stored in a dedicated high pressure gas. So when using the gas pressure drops through the valve test the required range, and then fine-tune after the other control valves, the gas entered the system. Oxygen valve is mandatory sealed valve, so when the valve is closed, the pressure must be applied to the valve to force the sealing surface does not leak. When the medium from the bottom of the six valve into the valve, the operating force required to overcome the resistance, the friction force and the thrust stem and packing by the pressure generated by the medium, close the valve opening force larger than the force of the valve, so that the valve The diameter of the rod to be large, otherwise the stem top corner of failures occur. From the self-sealing valve appeared medium flow shut-off valve on the flange into the valve chamber from the top to change the valve, then under media pressure, the valve off a small force, and force open the valve, the valve stem diameter can be reduced accordingly. Meanwhile, under the effect of the medium, this form of valve is also more closely. China's valve "three to" has been specified, as the flow valve, should be top-down. When the oxygen valve open, the valve opening height, the nominal 25% to 30% of the diameter, the flow rate has reached the maximum, the valve has reached the fully open position. So closing the valve fully open position, the valve stroke should be determined. 3] [oxygen valve Benefits - Riverstone valve a simple structure, manufacture and maintenance more convenient. 2, the working stroke is small, open and close a short time. 3, sealing, small friction between the sealing surface, longer life expectancy. 4] [oxygen valve Features - Riverstone valve 1) simple structure than the gate, manufacturing and maintenance are more convenient. (2) sealing surface easy to wear and abrasion, sealing, and no relative sliding between the valve and valve sealing surface when opening and closing, and thus wear and scratches are not serious, good sealing performance and long service life. (3) When opening and closing, the valve stroke is small, and therefore smaller than the height of the valve shut-off valves, but the structure is longer than the length of the gate. (4) opening and closing torque, relatively effortless opening and closing, opening and closing time of the principal. (5) fluid resistance, due to the valve body media path more tortuous, large fluid resistance, power consumption. (6) Nominal medium flow direction PN≤16MPa, generally used downstream, upstream from the media under the direction of the valve; when nominal PN≥20MPa, generally countercurrent, media orientation downstream from the valve. To increase the seal performance. When used, the cut-off valve medium can only flow in one direction, you can not change the direction of flow. (7) when fully open valve is often affected by erosion.