Mixproof valves are manufactured by M.S. Engineering [International] Services. Mix Proof Valve can be either double or single seated. A double-seated mix proof valve has two independent seals that separates the two liquids and a drainage chamber between. The drainage chamber is open to atmosphere to ensure full mixproof safety in case either of the two seals should leak. When a double-seated mix proof valve is activated, the chamber between the upper and lower body is closed and the valve opens to connect the upper and lower pipelines. When the valve is closed, first the upper plug seals and then the leakage chamber is opened to atmosphere. This gives very small product loss during operation. The single-seat mixproof valve has one seat and two seals, but on the same plug. The area between the two seals is open to atmosphere. This leakage drain chamber is closed by small shut-off valves before the single-seat mixproof valve is activated. An external CIP line is connected to the drainage line via the small valves for cleaning.
