The floating valve tray is a flat perforated tray with a floating disk (valve) mounted on each hole. At low vaporization rates, the disc can periodically drop into the hole and close it, thereby preventing fluid leakage. If the vaporization rate increases, the disk rises. The maximum valve opening depends on the valve legs height or on the fence construction.
Modern valve trays designs are based on standard float valves. They offer a wide adjustment range (5:1) and the choice of different valve thicknesses to meet the most of the requirements.