The Pt-drainage type cone is intended for the drainage of glass from forehearths in continuous operation. This drainage is recommended when viscous corrosion products of the refractory material that tend to crystallise sink to the bottom and cause defects in the product glass.
The drainage is pressed directly against the outlet opening in the bottom block.
The drainage consists of a platinum tube which can be fitted with a replaceable nozzle insert. Depending on the type of glass and the temperature, the attachment nozzle is dimensioned for the desired working range of the pull rate.
The platinum tube is directly electrically heated and temperature-controlled. No counter electrode is necessary.
For starting and for continuous operation, a burner heating with flame monitoring is additionally installed. The Pt-drain type cone is available as a stand-alone system or as an integrated part of a complete system.