Friction-free two-way hard seal butterfly pneumatic valve

frictionless two-way pneumatic valve adopts a hard seal butterfly butterfly plate can move along the axial pneumatic valve size structure, not only solved the problem hard seal butterfly two-way pneumatic valve seal, and make the pneumatic valve opening and closing torque is greatly reduced, greatly reducing the machining process. Its operation process is: from closed to open position is first disc axial move out of the pneumatic valve sealing surface, and then rotate ℃; From open to closed is butterfly plate rotating ℃ first, then the axial moving to the pneumatic valve sealing surface seal.
has the following advantages:
, truly hard seal butterfly pneumatic valve two-way full pressure seal.
conventional pneumatic valve butterfly butterfly plate fixed to the pneumatic valve stem and body in a pneumatic driving devices by rotating pneumatic valve stem disc of the switch. To the rotation of the pneumatic valve rod pneumatic valve stem and shaft sleeve ( Sliding bearing is clearance fit, that is a pneumatic valve stem and gap exists between pneumatic valve, pneumatic valve stem ( Butterfly plate in the four directions of pneumatic valve body relatively moving trend, pneumatic valve stem and valve clearance between the butterfly plate ( Pneumatic valve rod movement into reality, and the more the greater the seal clearance, so the direction of pressure testing often reliable sealing.
and imported from the opposite direction, the medium, there are two reasons cause can't seal. The first medium driven disc ( Pneumatic valve stem from pneumatic valve sealing surface produce clearance become impassable reality; Second, the butterfly plate and pneumatic valve rod under the action of medium is also the inevitable will produce deformation of immunity, will increase the gap between the sealing surface. This is a formidable problem for many years.
friction-free two-way hard seal butterfly butterfly plate of pneumatic valve in the pneumatic valve stem can be relative axial movement, not only from a pneumatic valve rod side introduced medium butterfly plate can move freely when the pneumatic valve sealing surface, can achieve reliable seal; When in reverse into medium, also can move to compensate for pneumatic by disc axial clearance between the valve stem and valve stem and pneumatic butterfly plate under the action of the force in the media and the pneumatic valve stem interference degree of deformation on the seal face clearance, achieve good sealing, achieve real two-way sealing.
, open-close torque decrease significantly.
greatly reduce torque for two reasons:
in the first place, the butterfly plate can move along the axial pneumatic valve size structure fundamentally eliminated the butterfly plate rotates the interference between the two cover, can be designed as single eccentric or pneumatic valve stem only deviate from the disc sealing surface, the butterfly plate radial eccentricity.
that is medium effect on the butterfly plate the force in pneumatic valve stem is complete symmetrical on both sides. Says from the principle of rotating disc overcome only pneumatic valve stem and shaft sleeve ( Sliding bearing friction torque. Compared with the double eccentric reduces the pneumatic valve stem from butterfly plate center caused by the unbalance torque.
second, butterfly plate ( Pneumatic valve stem opening and closing in on both sides of almost under the condition of constant pressure and torque.
the pneumatic valve rod opens, due to the butterfly plate will first from pneumatic valve sealing surface ( That is partially open, the medium pressure difference on both sides of the sealing surface will decrease rapidly. Butterfly plate ( Pneumatic valve rod rotation with sealing state ( Compared to conventional control pneumatic valve rotational state of medium force greatly decreases, and pneumatic valve stem and shaft sleeve ( Sliding bearing friction torque drops; Pneumatic valve closing, butterfly plate in the case of almost constant pressure on both sides, torque, smaller than open more than fear.
, the eradication of the pneumatic valve butterfly scrap caused by the friction losses between the sealing surface, will make the pneumatic valve life greatly improved.
the abandonment of pneumatic valve sealing surface leakage is the most main, the fundamental reason is that sealing surface is caused by the wear, frictionless two-way sealing butterfly pneumatic valves open and close, is in no friction state seal face will never be the leakage caused by friction, the service life of pneumatic valve will be improved to a great extent. Decided to pneumatic valve life in the future will not be pneumatic valve itself, the main is the use of corrosion medium. Therefore, for the severe corrosion medium pneumatic valve overhaul to multiple extended.
, pneumatic valve sealing surface of the positive cone by oblique cone instead, processing difficulty greatly reduced.
conventional hard seal butterfly pneumatic valve sealing surface oblique cone needs to make it, make it can be pressed tightly by rotating the cover. The existence of the problem is: not only to use sophisticated outfit, need large stroke machine, and discontinuous cutting accuracy is poor, sealing surface grinding fluid is difficult.
friction-free two-way hard seal butterfly pneumatic valve sealing surface without interference due to the opening and closing, sealing surface and compensation, sealing surface by oblique cone into a cone, eliminating the complex loading and processing difficulty is reduced greatly, and also facilitate grinding, more conducive to reliable seal.
, novel hydraulic device which can realize the movement of the pneumatic valve rod and rotate the two movements.