Eccentric Semi-ball Valve utilize dual-offset geometry (eccentric body & disc) to achieve: Progressive sealing force when closing； Full disc/seat separation when opening； This eliminates the constant friction inherent in conventional ball valves. Additionally: At full open: Disc retracts into the upper chamber, providing unrestricted flow and erosion immunity； At full close: Disc shears across the seat with scraping action, effectively clearing scale buildup.