Process Description :
Ladles are used to carry molten steel from the melting furnace to the ladle refining station or to the casting operation. These ladles must be preheated to minimize thermal shock and damage to the refractory lining and to reduce temperature drop in the ladle.

Equipments :
A covered ladle heating system consists of the following components:

Ladle Lid and Sealing System
In some systems the lid is lowered onto the vertical ladle, in others the ladle is tilted horizontally and brought up against the fixed face of the ladle heater. The sealing system can be either a ceramic fiber seal or an air curtain that eliminates cold air induction at the ladle mouth.

High Temperature Burner and Recuperator
The burner is designed to accept high temperature combustion air provided by a recuperator.

A temperature control system senses the ladle temperature and provides for turn-down of the burner for holding.

Technology :
Ladle preheating systems use a gas burner with a high turn down ratio. Excess air sensors maintain fuel mix control. Variable geometry flame can be provided for different ladle shapes to provide even heating. Recuperators can provide up to 1000° preheat.

Energy Consumption

Previous practice of heating ladles with an open burner has been replaced by the use of covered ladle heaters. For a 100 ton ladle, reheating an in-use ladle to a 2100°F hot face temperature requires 3.3 MMBtu of natural (0.033 MMBtu/ton) with a heating time of under one hour. Holding this same 100 ton hotladle at temperature requires 1. 4 MMBtu/hour (0.0124 MMBtu/ton).