A specially patented Ball Valve having TeflonPFA lining directly moulded on all surfaces having contact with the fluid. The thickness of the lining is calculated to ensure total protection against highly corrosive chemicals for long service life.Unlike conventional Ball Valves the ball assembly consists of one solid piece without any looseness so that there is no deterioration of lining in the area of Ball Stem Selding. The thickness of the lining is absolutely constant throughout to avoid any deformation of the ball.