Hydrant with automatic drainer and moving valve - has hollow seal for closing drain opening above valve

摘要

The hydrant with automatic drainer has draining opening on the side above the valve. This arrangement is designed to reduce cavitation noises and the cylindrical part of the hydrant can have wider tolerances without adversely affecting the reliability of the seal of the drain opening. The fitting of the seal on the closure element is also simplified. The cylindrical part (12) of the hollow seal (9) has an upper rim (11) and a transition section to the bottom edge (10) which is in contact with the closure unit (8). The rest of the hollow seal is not supported and it is held a distance apart from the closure unit. The bottom edge (10) of the hollow seal is connected to a clamped sealing ring (5) which is held between two plates (6, 7). This sealing ring acts as a seal for the main valve.