The series STH and STV, corresponds to a range of pre-filters of great capacity, which allow to catch any solid body in suspension in the fluid, thus avoiding its advance to the hydraulic unit of the pump.
Operation: The pressure of the fluid pushes the ball, which slides by some inner guides, staying in a lateral cavity of the body.
When the impulse stops, the ball lowers and is positioned in the hole of the valve inlet. The valve ensures a total flow of clean fluids or solids. Eliminates any risk of blockage by being the self-cleaning shutter (ball).