Hot galvanising inerior of shutter valve tongues - using pipe for escape of air when tongue enters treatment baths

摘要

Process for zinc coating hot blast shutter valve tongues by immersion in a bath of acid and then in a bath of zinc. The novelty is that prior to the treatment a suspension strap is attached to the rim, and a U-shaped pipe is inserted in the interior cavity of the tongue via the inlet for cooling water so that the end of the pipe in the cavity is near the rim, while the other end of the U shaped pipe projects beyond the rim on the outside of the tongue; the U-shaped pipe is used for the removal of air when the tongue is suspended by the strap and immersed in the baths, and, after treatment, both the strap and the pipes are removed. Hot galvanising of the interior of tongues used in valves on the air blast for blast-furnaces. Prevents corrosion of the tongue due to the cooling water and therefore prolongs the life of the tongue.