The throttle shut-off vent valve is widely used in oil.Natural gas.Gas.LPG refinery.Airport.Chemical.Oil and gas storage and transportation of pipelines for closed-circuit devices.

throttling shut-off venting valve standard

The applicable standard shut-off valve is only applicable for full opening and full closing, and is not allowed to be used for regulation and throttling.The shut-off valve is a forced sealing valve, so when the valve is closed, pressure must be applied to the valve flap to force the sealing surface not to leak.When the medium enters the valve from the bottom of the valve flap, the operating force needed to overcome the resistance, is the friction of the stem and packing and the thrust generated by the pressure of the medium, the force to close the valve is larger than the force to open the valve, so the diameter of the stem should be large, otherwise the stem will occur the top bend failure.In recent years, from the emergence of self-sealing valves, the media flow direction of the globe valve is changed from the valve flap above the valve cavity, then under the pressure of the medium, the force off the valve is small, and open the valve force is large, the diameter of the valve stem can be reduced accordingly.

The diameter of the valve stem can be reduced accordingly.

throttling shut-off venting valve model

Imported globe valve.Electric globe valve J941H-16.High pressure electric globe valve J941H-320.Japanese standard globe valve J40H-10K.German standard globe valve J41H-16.American standard globe valve J41H-150Lb.Japanese standard stainless steel globe valve J41H-16P.German standard stainless steel globe valve J41H-16P.American standard stainless steel globe valve J40H-30Lb.High temperatureGlobe valve J41Y-16I.

throttling shut-off venting valve working principle

Normally closed state: the hard seal of the valve flap is pressed on the convex platform of the valve seat, forming a hard seal, while the soft seal embedded in the valve flap is pressed against the end face of the valve seat, forming a second seal, the double seal structure ensures zero leakage of the valve, and then because the valve flap is opened with a balance hole, so that the valve is closed.When the valve is opened, the flap is subjected to a small force, which also makes the valve open.Close with a small torque.Slow pressure state: the bottom end of the valve flap leaves the seal surface of the valve seat, because the bottom surface of the valve flap is close to the bottom edge of the cage sleeve open bad, then the valve flap and the cage sleeve inside diameter to form a seal.And no direct venting pressure relief, so as to achieve a moderating effect.