An Aluminum Transfer/Launder System is designed to safely, efficiently, and continuously transport molten aluminum from melting or holding furnaces to casting machines, refining units, or downstream equipment.
The system consists of five core sections:
Located at the furnace outlet, this section opens, stops, and precisely regulates the flow rate of molten aluminum leaving the furnace.
Tap Hole Block & Sleeve: Made from highly wear-resistant and erosion-resistant materials such as silicon nitride bonded silicon carbide (Si₃N₄-SiC) or high-purity corundum precast shapes.
Stopper Pin & Cone: Used for mechanical or manual opening and sealing of the tap hole.
Actuated Flow Control Pin: Works with level sensors to automatically adjust the flow rate of molten aluminum.
The "veins" of the system that guide the molten aluminum launder to its destination.
Outer Steel Casing: Provides structural support, often integrated with tilting or rotating mechanisms.
Insulation Layer: Positioned against the inner wall of the steel shell, utilizing microporous insulation boards or AES (Alkaline Earth Silicate) soluble eco-friendly fibers to minimize heat loss and lower shell temperature.
Refractory Launder Lining: The core lining in direct contact with molten aluminum, typically made from fused silica, aluminum titanate, or high-performance anti-wetting castable precast shapes, offering non-wetting properties and excellent thermal shock resistance.
Launder Covers & Preheating System: Covers fitted with heating elements (heating rods or gas burners) for preheating before operation and maintaining temperature during transit.
Continuously degas and filter the molten metal during transfer to ensure casting quality.
In-Line Degasser: Uses rotating impellers to inject argon or nitrogen (sometimes with small amounts of chlorine) to remove hydrogen gas and inclusions.
Filter Box: Houses ceramic foam filters (CFF) or rigid media tube filters to trap micron-sized oxide inclusions.
Grain Refiner Wire Feeder: Continuously feeds grain refining wires (e.g., Al-Ti-B) directly into the launder stream.
Nodes that split, redirect, or feed the liquid metal.
Distribution Box & Diverter: Splits a single metal stream into multiple paths feeding different casting lines or molds.
Tilting / Flexible Launder: Allows angle adjustments when connecting crucibles, main launders, and casting machines.
Casting Thimble & Downspout: Positioned at the end of the transfer line to smoothly deliver metal into casting molds or direct chill (DC) casting tables.
Ensures process safety and precision monitoring across the entire transfer line.
Laser / Ultrasonic Level Sensors: Continuously monitor metal depth in the launder and provide feedback to the flow control pin.
Thermocouples: Track molten aluminum temperatures across different launder sections and degasser boxes.
Emergency Dump System: Automatically discharges molten metal into a safety dump pit if downstream equipment stops, preventing metal from freezing inside the launders.
