Simple Solutions That Work! Issue 16

28 TREATMENT LADLES Things get a bit more complicated when it comes to the treatment ladles. We refer to treatment ladles as any ladle that is used for the in ladle production of ductile iron, which covers a wide range of both specially designed ladles and ladles that are pressed into service for this role. We usually assume this term to encompass deep treatment, wire feed, tun-dish and so on. The Acetarc names tend to get literal and we are aware that certain types are known, especially in the USA by other established names. So it is sometimes best to describe both the function and the operation of the ladle just to make sure that we are all talking about the same type of ladle. For example; we’ve got our teapot spout treatment ladle but that type is probably better known in the USA as the mod tundish or even “pressure” tundish. We first made this type of ladle back in the early 1980’s for a customer in Scandinavia and I thought it was called a Kockums type ladle until I realized that was the name of the foundry and not the process. Then we have “fixed” tundish, where the tundish cover stays on the ladle throughout its working shift and the metal is both poured in and out via the tundish box. Again in the USA, this is often referred to as a “tight cover” treatment ladle. Many foundries, since they usually only use one treatment process often refer to their ductile ladle as the treatment ladle regardless of what process they actually use. It is sometimes necessary to ask several basic questions to establish just exactly what the foundry requires and apologies to anybody if it seems like I’m teaching you “how to suck eggs.” I do find that taking things back to the basics, while it runs the risk of coming across as patronising—–or making me look like an idiot, is the best way of removing any confusion. Another point is how ladles are named relative to their capacity or size. We refer to ladles by their rated working capacity for example: 1000 Kg capacity or 2200 lb capacity. The capacity is always the working capacity of the ladle and not the brim capacity. However, some foundries refer to their ladles by the size; typically, the top diameter, so instead of 2200 lb they would call the ladle an Ø30.” As the ladle shell sizes often reflect the lining and freeboard requirements, we prefer to go on the working capacity as a 2200 lb capacity ladle for one foundry can be a difference size for another one. A couple of important terms here are FREEBOARD and WORKING CAPACITY. Freeboard: the distance from the top of the metal to the brim of the ladle. Working capacity: the rated capacity of the ladle when it is filled to give the indicated freeboard (for a given lining allowance and molten metal density). We never rate the capacity of the ladle as if it is filled to the brim—which we strongly do not recommend. After all you wouldn’t fill your coffee mug to the brim as you would just end up with spilled hot coffee.