Simple Solutions That Work! Issue 9

It is a simple enough concept that the goal of any molten metal processing business should be to finish the process with the amount of metal for sale that is as close as possible to the amount you started with. Whether you start with ingot, scrap or molten aluminum, the closer you can get to 100% utilization, the better. As we all know, this is easier said than done, and depending on what type of process you are running, there can be many areas where metal is “lost.” When molten aluminum oxidizes to create dross, the value of that lost metal can never be fully recovered. This has an immediate negative impact on profitability, and so focusing on areas where metal loss can be reduced is vital to the health of your business. One of the areas where this type of loss occurs is when metal is being transferred out of the furnace. Let’s look at some of the ways we can minimize metal loss in the metal transfer process. Metal Loss During Transfer There are essentially 3 methods for transferring metal out of reverberatory furnaces. The first is to use a tap out plug and gravity and to transfer the metal by removing the tap out plug and allowing gravity to drain the furnace. The second method is to use a traditional transfer pump with a riser tube and piping to mechanically lift the metal out of the furnace and transfer it through the piping to the point of next use. The third method is to use a launder transfer pump which also mechanically lifts the metal out of the furnace but does so without the need for piping and instead uses a chimney and a launder (trough) to transport the liquid metal. Let’s examine each of these methodologies as it relates to PAUL COOPER President MOTLEN METAL EQUIPMENT INNOVATIONS ARTICLE TAKEAWAYS: • Reducing metal loss should be a primary focus of all foundries/die casters • Understanding dross creation and metal loss • Metal transfer techniques - reduce dross creation & save money MINIMIZING DROSS CREATION IN MOLTEN ALUMINUM TRANSFER 24