Precast ceramic linings for launders, snouts, tundishes and pour cups in aluminum, copper and specialty alloy casting.
Between furnace and mold, the metal runs along ceramic.
That surface decides what the metal picks up on the way.
Launder and tundish materials that resist molten metal are chosen by the alloy: for aluminum, non-wetting OXYTRON oxide bonded and NITRON nitride bonded silicon carbide, with alumina and mullite where thermal shock dominates; for nickel, cobalt and stainless alloys, ProCaster high alumina and the alumina zirconia Procaster-Z. Blasch casts these linings as precast shapes with smooth surfaces, which keeps sticking, metal penetration and inclusions low. Joints, filter grooves, nozzle pockets and heater channels are cast into the lining.
A launder carries molten metal in an open channel from the furnace to the casting station, often through degassing and filtration on the way. A tundish or pour cup collects the metal and feeds it at a controlled rate into a mold, a casting machine or an atomizing nozzle.
The ceramic lining is the part the metal touches. It has to resist attack by the alloy, survive the thermal cycling of every start and stop, and keep a surface that metal does not stick to.
Heat loss is the other half of launder design. Insulation behind the lining and heated sections keep the metal at temperature over the length of the run, and the lining shapes can carry channels for heater elements.
Metal that leaves the furnace clean can still pick up oxides and inclusions on its way to the mold, and the launder lining is where that happens.
The Blasch process forms these details in the ceramic, so they do not have to be cut or assembled on site.
Tortuous joints between sections that keep metal from finding a straight path through the lining.
Grooves that hold ceramic filters in place in the launder or tundish.
Precise seats for the nozzle at the outlet of a tundish or pour cup.
Channels that take heating elements for heated launder sections.
| Alloy | Lining material |
|---|---|
| Aluminum alloys | OXYTRON oxide bonded SiC, NITRON nitride bonded SiC |
| Aluminum with heavy thermal cycling | Alumina, mullite |
| Copper and brass | NITRON, OXYTRON |
| Nickel, cobalt, stainless | ProCaster high alumina, Procaster-Z alumina zirconia |
Procaster-Z is rated to 1,650 °C (3,000 °F) in continuous service and is used for tundishes, launders and pour cups in specialty alloy melting.
In powder production, the tundish feeds the atomizing nozzle, and its flow decides how evenly the stream reaches the gas jets. Blasch makes tundish, pour cup and nozzle as matched parts, and can assemble them before delivery. Ceramic atomizing nozzles
The outlet of a launder or tundish is a pour spout or metering nozzle, and filtering the stream is done with printed ceramic filters set into the cast grooves.
A launder is a channel that carries metal from one place to another. A tundish is a vessel that collects the metal and feeds it at a controlled rate through a nozzle.
Blasch tundishes are made for specialty alloy casting, aluminum and gas atomization. Large steel tundishes lined with gunned or cast refractory are a different product.
Yes. Sections are cast to the dimensions of your launder casing, with the joints, grooves and pockets you need.
Send the launder or tundish dimensions and the alloy. A Blasch engineer proposes the material and the cast features.
