Apparatus and method for delivering an inert gas to prevent plugging in a slide gate
AssigneeISG Technologies Inc.
InventorBruce R. Forman
Life of this patent
Estimating the term…
Abstract
The invention is directed to a dynamic control system that maintains an inert gas feed at a constant target gas flow rate sufficient to prevent or reduce alumina or alloy plugging within a slide gate discharge opening. The dynamic control system includes a gas feed line extending between an inert gas supply and the slide gate discharge passageway, a gas flow regulator, a pressure gauge; and a gas feed flow control that detects an amount of incoming inert gas lost through leaks in the system and adjusts the gas flow regulator in response to the detected amount of incoming gas flow loss so that the adjusted incoming gas feed continues to deliver the target inert gas flow rate to the discharge passageway.
Claims21
Apparatus to deliver inert gas at an incrementally adjusted target flow rate to a discharge passageway in a slide gate that drains liquid steel from a tundish into a continuous caster, comprising:
- a) a gas feed including an inert gas supply, a gas feed line extending between said inert gas supply and the discharge passageway to deliver an incoming gas flow to the discharge passageway, a gas flow regulator, and a pressure gauge;
- and
- b) a gas feed flow control that detects an amount of incoming gas flow lost through leaks in said apparatus, and incrementally adjusts said gas flow regulator in response to said detected amount of incoming gas flow lost through leaks so that said incoming gas flow is adjusted to deliver said target flow rate of inert gas to the discharge passageway.
A method for operating a gas delivery system that provides an incrementally adjusted target gas flow rate of inert gas to a discharge passageway in a slide gate that drains liquid steel from a tundish into a continuous caster, the steps of the method comprising:
- determining an amount of inert gas lost through leaks in said gas delivery system, said amount of inert gas lost to leaks determined from a measured back pressure in said gas delivery system, a measured incoming gas flow rate in said gas delivery system, a gas flow resistance calculated from said measured back pressure and said measured incoming gas flow rate, and a static pressure of the liquid steel draining through the discharge passageway, and
- incrementally adjusting said incoming gas flow rate in response to said determined amount of inert gas lost to leaks so that said target gas flow rate of inert gas is delivered to the discharge passageway.
A method for maintaining a target flow rate of inert gas to a discharge passageway in a slide gate that drains liquid steel from a tundish into a continuous caster, the steps of the method, comprising:
- providing an incoming inert gas feed at a desired gas flow rate set point
- delivering said incoming inert gas feed to the discharge passageway;
- operating the continuous caster at a steady-state casting condition;
- determining static pressure of the liquid steel draining through the discharge passageway;
- adjusting incrementally incoming inert gas feed to a higher gas flow rate;
- determining when said adjusted incoming inert gas feed produces a back pressure in the inert gas feed that is greater than said static pressure of the liquid steel draining through the discharge passageway;
- determining flow resistance in the incoming inert gas feed when said produced back pressure is greater than said static pressure of the liquid steel draining through the discharge passageway;
- detecting an amount of incoming inert gas lost through leaks in said incoming inert gas feed, said amount of incoming inert gas lost to leaks determined from said produced back pressure, a measured incoming gas flow rate in said gas feed, said gas flow resistance, said static pressure of the liquid steel draining through the discharge passageway, and
- adjusting said measured incoming gas flow rate in response to said detected amount of incoming inert gas lost to leaks so that said target flow rate of inert gas is delivered to the discharge passageway.
Dependencies are inferred from the claim text.