The Pt-drainage type double tube is intended for the drainage of glass from furnaces and 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 melt enriched with corrosion products can be removed with this drainage.
The drainage consists of a platinum tube which is installed at the bottom of the refractory and extends trough the brick to the inner edge. An exchangeable attachment nozzle can be installed on the platinum tube. Depending on the type of glass and the temperature, the attachment nozzle is adapted to the desired working range of the pull rate.
The platinum tube is directly electrically heated and temperature-controlled. No counter-electrode is necessary.
For start-up and flow control, a burner heating or an inductively heated outlet nozzle is additionally installed.
The Pt-drainage type double tube is available as a stand-alone system or as an integrated component of a complete plant.