The drossbox is an intermediate (transition) area between the tin bath and the annealing lehr. The purpose of the drossbox is to ensure maximum sealing of the tin bath exit and also to prevent the ambient air from entering the tin bath through the exit opening. Sealing is achieved due to the closed structure of the drossbox and through the supply of nitrogen – inert gas – into the drossbox.
It contains a lower part which is equipped with three height-adjustable lift out rollers for lifting the glass from the tin surface and pull it into the lehr.The Drossbox will be closed through the upper part. This part includes four drapes. These drapes are vital pieces of equipment to control the pressure and chemistry of the bath. They should be maintained regularly and fully functional at all times.
One above the exit lip and one above each of the three lift out rollers.
They should be lowered close to the glass and should be adjusted after every thickness change. They can be driven either manually or electronically.
A special removing tool and also the construction of the drossbox will allow you to install and dismantle the lift out rollers without interrupting the glass production.