Direct chill casting under protective atmosphere

Claim 3

A method as set forth in claim 1 wherein said inhibiting fire further comprises exhausting flammable vapors from a cooling zone proximate to said direct chill cooling and terminating said exhausting while covering said coolant with said fire retardant atmosphere.

Claim 4

A method as set forth in claim 2 wherein said covering comprises dispersing said atmosphere and protecting against metal splash from said ingot.

Claim 5

A method as set forth in claim 3 further comprising sparging said coolant to remove moisture in a sparging reservoir separate from said cooling zone.

Claim 6

In a process for continuously casting a metal alloy comprising cooling molten alloy in a shell-forming zone and further cooling said alloy by direct chill with a coolant to form a continuous ingot, the improvement comprising: casting lithium-containing alloy; performing said direct chill cooling with a coolant comprising a modified hydrocarbon coolant; and inhibiting fire associated with said coolant by incorporating fire retardant atmosphere covering said coolant.

Claim 7

In a process for continuously casting a metal alloy comprising cooling molten alloy in a shell-forming zone and further cooling said alloy by direct chill with a coolant to form a continuous ingot, the improvement comprising: casting lithium-containing alloy; performing said direct chill cooling with a coolant comprising a modified hydrocarbon coolant; and inhibiting fire associated with said coolant by incorporating fire retardant atmosphere covering said coolant.

Claim 8

The process as set forth in claim 5 wherein said fire retardant atmosphere comprises a blanketing atmosphere of non-combustive, non-reactive gas.

Claim 9

The process as set forth in claim 6 wherein said non-reactive gas comprises an inert gas or a gas that will not support combustion or mixtures thereof.

Claim 10

The process as set forth in claim 7 wherein said fire retardant atmosphere consists essentially of carbon dioxide.

Claim 11

The process as set forth in claim 8 wherein said atmosphere is discharged through a conical nozzle to disperse the gas and to protect from metal splash from the ingot.

Claim 12

The process as set forth in claim 9 wherein said fire retardant atmosphere is contained in a zone proximate to said direct chill cooling by cover plates.

Claim 13

A process for continuously casting an aluminum alloy containing over about 1.5% by weight lithium into a solidified ingot having a smallest transverse dimension greater than about six inches, comprising: initiating solidification of liquid alloy into an ingot in a continuous casting mold; direct chill cooling said ingot with a coolant comprising an organic coolant and a moisture content less than an amount predetermined to avoid explosions during said casting operation, said coolant being applied to the surface of said ingot and separating therefrom; collecting said coolant separating from said ingot in a collection pool; inhibiting fire by covering said coolant with a protective atmosphere; and recirculating said coolant from said collection pool for further direct chill cooling.

Claim 14

A process for continuously casting an aluminum alloy containing over about 1.5% by weight lithium into a solidified ingot having a smallest transverse dimension greater than about six inches, comprising: initiating solidification of liquid alloy into an ingot in a continuous casting mold; direct chill cooling said ingot with a coolant comprising an organic coolant and a moisture content less than an amount predetermined to avoid explosions during said casting operation, said coolant being applied to the surface of said ingot and separating therefrom; collecting said coolant separating from said ingot in a collection pool; inhibiting fire by covering said coolant with a protective atmosphere; and recirculating said coolant from said collection pool for further direct chill cooling.

Claim 15

A process as set forth in claim 11 further comprising an alternate step of exhausting vapors from a cooling zone proximate to said direct chill cooling.

Claim 16

A process as set forth in claim 12 comprising sparging said coolant to remove moisture in a sparging reservoir separate from the cooling zone.

Claim 17

A process as set forth in claim 13 wherein said cooling zone comprises a boundary of atmosphere-containing cover plate.

Claim 18

A process as set forth in claim 14 wherein said covering said coolant comprises discharging said atmosphere through a conical nozzle to disperse the atmosphere and protect the exit orifice from metal splash.

Claim 19

A process as set forth in claim 15 wherein said exhausting vapors comprise withdrawing vapors from the cooling zone through said conical nozzle.

Claim 20

A process as set forth in claim 16 wherein said organic coolant comprises ethylene glycol.

Claim 21

A process as set forth in claim 17 wherein said organic coolant comprises ethylene glycol and less than about 10% moisture.

Claim 22

A process as set forth in claim 18 wherein said atmosphere comprises an inert gas, nitrogen, carbon dioxide, or mixtures thereof.

Claim 23

A process as set forth in claim 19 wherein said fire retardant atmosphere consists essentially of carbon dioxide.