The entrance coolers are used to extract heat from the glass ribbon at the front of the bath. They will be inserted from both sides of the bath. The cooling rails cross each other in the center of the furnace in order to extract more heat from the direct center than from the edges.
The main function of the entrance cooler is to cool down the glass ribbon to the correct temperature for the forming process.
The cooling rails will enter the tin bath through the letterbox side sealing. If the cooler will be removed of the tin bath the side sealing will close the opening automatically. This process is helpful in order to prevent the penetration of ambient air into the tin bath.