Ladle (metallurgy) Pour designs

Ladles can be of "lip pour"design, "teapot spout" design, "lip shaft design" or "bottom pour" design:For lip pour designs, the ladle is tilted and the molten metal is poured from the ladle like water from a pitcher.Teapot spout design, like a teapot,draws liquid from the bottom of the spoon and pours it out through the lipped spout.Any impurities in the molten metal form on top of the metal,so by taking the metal from the bottom of the ladle, the impurities do not pour into the mold.The same idea is behind the bottom pouring process.The vessel pivot point of the lip shaft ladle is as close as possible to the tip of the gate.As a result, the actual pouring point barely moves as the ladle rotates.Lip shaft pouring is typically used in molten metal pouring systems where it is desirable to automate the process as much as possible and for the operator to remotely control the pouring operation.

For bottom cast ladles, insert the plug rod into the tap hole in the bottom of the ladle.When pouring metal, the plug is lifted vertically to allow the metal to flow from the bottom of the ladle.To stop pouring, insert the stopper stem back into the weep hole.Large ladles in the steelmaking industry may use sliding doors below the taphole.Ladles can be open at the top or covered.Covered ladles have a (sometimes removable) dome-shaped cover to contain radiant heat; they dissipate heat more slowly than open ladles.Ladles usually don't have lids, but ceramic blankets can be used instead (if available).

Medium and large ladles suspended from cranes have an eye, called a trunnion, that holds the ladle to the shaft.For tilting the ladle, a gearbox is used, which is usually a worm gear.The gear mechanism can be operated manually with large wheels, or with electric or air motors.Powered rotation allows the ladle operator to move to a safe distance and control the rotation of the ladle from a pendant or radio remote.Powered rotation also allows for multiple rotational speeds of the ladle, which may benefit the entire casting process.The powered rotation also obviously reduces the workload required of the ladle operator and allows for the transfer and pouring of large quantities of molten metal for extended periods of time without operator fatigue.If the ladle has a manual transmission, the most common type of transmission is the worm gear design, as in most practical cases it can be considered "self-locking" if properly maintained and does not require internal friction brakes to adjust the ladle the tilting speed.Other types of gear systems can also be used, but they must be equipped with an additional braking system to hold the ladle in place when the operator removes his hand from the hand wheel.

Lip shaft ladles can also use hydraulic cylinders to tilt the ladle.The largest ladles have no gears and are usually poured using special twin-winch cranes, where the main winch carries the ladle while the second winch engages with lifting lugs at the bottom of the ladle. Raise the second winch and spin the ladle on the trunnion.Ladles are usually designed for special purposes, such as adding alloys to molten metal.Ladles may also have porous plugs inserted into the bottom so inert gas can be bubbled through the ladle to enhance alloying or metal treatment practices.