How to remove double eccentric flanged butterfly valves fault
Double eccentric flanged butterfly valves, which is characterized in that the pump valve seat sealing ring made of soft T – shaped sealing rings on both sides of the composition of multi-layer stainless steel sheet.
First, as hard and soft layers stacked ring fixed in the valve plate, when the pump valve plate normally open state media, the formation of the front sealing surface erosion, and metal sheets laminated in the soft seal by brushing with a direct impact on seal performance.
Two, by the structural constraints of the structure do not meet the following path DN200 valve, valve plate due to the overall structure of thick, large flow resistance.
Three, because of the principle of the three eccentric structure, the sealing between the valve plate and valve seat sealing surface is on the transmission of torque to the valve plate to the valve seat pressure. Positive flow state, the higher the pressure medium sealed tight squeeze. When the counter current flow when the medium between the valve plate and valve seat with the increase of medium pressure units is less than the pressure medium pressure, the seal began to leak.
Valve plate and valve seat sealing surface for the oblique cone structure, in the valve plate oblique conical surface of welding temperature corrosion resistant alloy material; the structure is fixed between the adjusting ring plate spring and a pressure plate with the adjusting screw assembly. This structure effectively compensate for elastic tolerance between the sleeve and the valve stem in the medium zone and deformation under pressure to solve the sealing problems during valve in the two-way exchange of the medium transport.
Using the soft of T type sealing ring on both sides of the composition of multi-layer stainless steel sheet, and has dual advantages of metal hard seal and soft seal, both in low and high temperature conditions, both with zero leakage sealing performance. Pool tested positive flow state (medium flow direction and the disc rotating in the same direction), the sealing surface pressure is generated torque and media pressure on the valve plate driving device. Positive medium pressure increases valve plate and valve seat surface and oblique cone sealing surface squeezed more tightly, sealing the better.
When the current state, sealed by the drive torque to the valve plate to the valve seat pressure between the valve plate and valve seat. With the reverse medium pressure, valve plate and seat unit between the positive pressure is less than the medium pressure, the adjustment ring spring deformation after loading can be stored in the compensation valve plate and valve seat sealing surface of the tight pressure to play the role of automatic compensation.
Therefore, the utility model unlike existing techniques that software and hardware installed in the valve plate multi ring, but directly installed on the valve body, the middle seat in the plate and an additional adjustment ring is a very good two-way hard sealing method. It can replace the valve and ball valve.
Post time: Nov-07-2018