What are the advantages of triple eccentric metal hard seal butterfly valve
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: at present, butterfly valve, as a kind of used to realize on-off and flow control components, piping system has been used in petroleum, chemical industry, metallurgy, water and electricity is widely used in many fields such as extremely.
In butterfly valve technology has been known, its seal form with seal structure, sealing materials for rubber, ptfe, etc.
Because of the limitation of structural features is not adapt to the high temperature, high pressure and corrosion resistance, wear resistance, etc.
Existing a more advanced butterfly valve is a triple eccentric metal hard seal butterfly valve, the valve body and seat for the Siamese components, valve seat sealing surface layer welding temperature resistant, corrosion resistant alloy material.
Multilayer soft fold type sealing ring is fixed on the valve plate, the butterfly valve and the traditional butterfly valve compared with high temperature resistant, convenient operation, opening and closing without friction, closed as the actuator torque increases to compensate for sealing, improve the butterfly valve sealing performance and prolong the service life of the advantages.
But, this kind of butterfly valve in use process still exist the following problems, due to multi-layer soft fold type sealing ring is fixed on the valve plate, when the valve plate normally open state media on the sealing surface to form positive scour, soft sealing strip of metal sandwich after flushing, directly affect the sealing performance.
Second, restricted by structure condition of the structure is not adapt to do diameter DN to the following valves, reason is the valve plate structure is too thick, large flow resistance.
Third, because of the principle of triple eccentric structure, between the sealing surface of valve plate and valve seat sealing is to rely on the drive torque valve plate pressure to the valve seat.
Is flow state, the higher the medium pressure seal compression tight.
When the countercurrent flow medium with the increase of medium pressure valve plate and valve seat unit is less than the pressure medium, the positive pressure between seal began to leak.
High performance three eccentric two-way hard seal butterfly valve, and its features are described in the seat sealing by soft t-shaped sealing ring on both sides of the multi-layer pieces of stainless steel.
Valve plate and valve seat sealing surface for the oblique cone structure, the valve plate oblique cone surface welding heat resistance, corrosion resistant alloy material;
Fixed between the adjusting ring clamp spring together with the clamp on adjusting bolt assembly structure.
This structure can effectively compensate the tolerance zone between sleeve and body and the elastic deformation of the stem under medium pressure, solve the valves in the process of the two-way exchange medium conveying the sealing problems.
Soft T on both sides of the multi-layer stainless steel pieces of sealing ring, with metal sealing and soft sealing the dual advantages of under low temperature and high temperature circumstances, all with zero leakage sealing performance.
Trials show that pool is flow state (
Medium flow direction is same as the rotation direction of the butterfly plate)
When the sealing surface pressure is the drive torque and medium pressure in the valve plate.
Positive medium pressure valve plate oblique cone surface and valve seat sealing surface squeezed more tightly, sealing effect is better.
When the current state, between the valve plate and valve seat sealing pressure on drive torque make the valve plate to the seat.
As the reverse medium pressure increases, the unit is pressure between the valve plate and valve seat is less than the pressure of medium, the adjusting ring after the loading of the spring deformation energy stored by compensating valve plate and valve seat sealing surface of the tight pressure automatic compensation effect.
So the utility model is not like the existing technology, soft hard multi-layer sealing ring, installed in the valve plate directly installed on the valve body, in the middle of the plate and seat add adjustable ring is the ideal way of two-way hard seal.
It will replace gate valve, globe valve and ball valve.