Since the existed butterfly valvs for waterworks is light than sluice valve, compact and easy for opening & closing and in case it is the electric power, the power motor is a few and installaton is easy, it is widely used, and it is excellent for exponential abillty because rubber will be used to valve body or one side of seat surface of disk. However, according to the using condition, it will have damage to the rubber seat and when it will be used for long period, the exponential ability will be remarkably dropped that is main role of valve by the old of rubber or hardening phenomenon, and in cafe of metal seat to be sold after development in recent, the exponential ability also will be dropped and come to factor of leakage since metal seat will have damage in case of sticking sand or other alien substances between seats 
 Acoordingly, the Soft metal seat butterfly valve developed by YiHWAN Industrial Company is the soft metal seat valve that the triple exponential method united metal seat without abnormality in the time of the long time use by the excellent life of rubber seat, in other not to give damage to the metal seat in the severe using conditions and it is the excellent products to contribute to decrease maintenance costs.  
  

Feature of Products(3 Stage of Exponential Method) 

1.As a Disk Seat Structure Triple Sealing Valve. AS it is METAL TO NBR, METAL TO METAL, METAL TO NBR, we can secure perfect watertight 

2.When anti-pressure will be occurred, it will be possible for watertight or decrease of pressure, watertight or decrease of pressure in 2nd stage of metal seat, and perfectly maintains anti pressure and air tightness in the triple rubber seat. 

3.Since shaft center is with eccentric structure, the seat abrasion and damage of seat from friction between disk rubber seat or metal seat of valve body will be prevented in the time of opening and closing 

4.In order to prevent to be damaged seat by incoming of sand and alien substances that is demerit of the general metal seat, the soft metal seat has the type that will clean after pushing the sand or alien substances by rubber seat and therefore, it will prevent damage of metal seat