Method and apparatus for continuous casting

Claim 3

The method of claim 1 wherein said mixture of lubricant and gas is formed in a ratio by volume of between about 1:1000 and 4:1000.

Claim 4

The method of claim 1 wherein said mixture comprises a separating agent and gas.

Claim 5

The method of claim 1 further comprising providing a starter block in said mold before the introduction of said material to be cast.

Claim 6

The method of claim 4 wherein said starter block has a perimeter less than the perimeter of said inner wall surface of said chill.

Claim 7

The method of claim 1 further comprising providing a vacuum between said inner wall surface of said chill and said material to be cast and/or said starter block.

Claim 8

The method of claim 6 wherein said vacuum is created by providing a liquid cooling stream against the surface of the material to be cast and below said inner wall surface of the chill.

Claim 9

The method of claim 1 wherein the material to be cast forms a meniscus at the transition of said overhand and said inner wall surface of said chill.

Claim 12

The method of claim 9, wherein the step of introducing at a transition includes suctioning the mixture to flow through said gap.

Claim 13

The method of claim 9, wherein the flow is laminar.

Claim 14

A continuous casting annular mold, comprising: an annular superstructure; an annular chill secured below the superstructure, the chill having a smooth inner all surface which extends away from the superstructure, the super-structure including an overhang, the chill including means for cooling the inner wall surface; a gas supply line for supplying gas to flow in a direction parallel to the inner wall surface of the chill before reaching a juncture of the overhang and the inner wall surface of the chill; a lubricant supply line for supplying lubricant to the gas supply line upstream of the juncture so that a mixture of the lubricant and the gas emerges to flow from the gas supply line in a direction parallel to the inner wall surface of the chill; and means for maintaining a gap between the inner wall surface and a molten material which is beneath the overhang by flowing the mixture through the gap so as to avoid lubricant combustion, subsequent underdosing of the lubricant along the inner wall surface of the chill, and liquation and tacky area formation of the molten material being cast, whereby the mixture flows through the gap and the molten material remains spaced apart from the inner wall surface during passage of the molten material through the mold.

Claim 15

A continuous casting annular mold, comprising: an annular superstructure; an annular chill secured below the superstructure, the chill having a smooth inner all surface which extends away from the superstructure, the super-structure including an overhang, the chill including means for cooling the inner wall surface; a gas supply line for supplying gas to flow in a direction parallel to the inner wall surface of the chill before reaching a juncture of the overhang and the inner wall surface of the chill; a lubricant supply line for supplying lubricant to the gas supply line upstream of the juncture so that a mixture of the lubricant and the gas emerges to flow from the gas supply line in a direction parallel to the inner wall surface of the chill; and means for maintaining a gap between the inner wall surface and a molten material which is beneath the overhang by flowing the mixture through the gap so as to avoid lubricant combustion, subsequent underdosing of the lubricant along the inner wall surface of the chill, and liquation and tacky area formation of the molten material being cast, whereby the mixture flows through the gap and the molten material remains spaced apart from the inner wall surface during passage of the molten material through the mold.

Claim 16

The continuous casting mold of claim 2 wherein said gas supply line terminates at an annular gap within said supersturcture, said annular gap disposed parallel to said inner wall surface of said chill, and terminating at the transition of said overhang and said inner wall surface of said chill.

Claim 17

The continuous casting mold of claim 13 wherein said lubricant supply line terminates at said annular gap at a point downstream of the termination point of said gas supply line.

Claim 18

The continuous casting mold of claim 13 wherein said annular gap is about 10-30 millimeters in length.

Claim 19

The continuous casting mold of claim 11 wherein said lubricant supply line terminates about 2-10 millimeters above said transition of said overhang and said inner wall surface of said chill.

Claim 20

The continuous casting mold of claim 12 wherein said cooling means includes a cooling reservoir within said chill.

Claim 21

The continuous casting mold of claim 12 further comprising a gas conduction block mounted between said chill and said superstructure.

Claim 22

The continuous casting mold of claim 18 wherein said gas supply line passes through said gas conduction block.

Claim 23

The continuous casting mold of claim 12 further comprising a gas ring along the path of said gas supply line.

Claim 24

The continuous casting mold of claim 12 further comprising a starter block surrounded by said annular chill, said starter block having a perimeter such that there is a gap of about 2 to 5 millimeters between the starter block surface and said inner wall surface of said chill.

Claim 25

The continuous casting mold of claim 21 wherein said starter block includes a peripheral raised edge at its upper end.

Claim 26

A continuous casting annular mold, comprising: means for cooling an inner wall surface of a chill, the inner wall surface extending away from a superstructure of a continuous annular casting mold; means for directing a gas to flow under pressure parallel to the inner wall surface of the chill toward an area of transition of the overhang and the inner wall surface of the chill; means for directing a lubricant to mix with the flow of gas upstream of the transition so as to provide a mixture of the lubricant and gas under pressure in which the mixture flows in a direction parallel to the inner wall surface of the chill toward the transition; means for introducing at the transition of the overhang of the superstructure and the inner wall surface of the chill the mixture of the lubricant and gas under pressure; means for directing the mixture to flow before the mixture reaches the transition in a direction which is parallel to the inner wall surface of the chill and thereafter through a gap between the inner wall surface and a molten material to be cast; means for introducing the molten material to be cast adjacent to the overhang; and means for keeping the molten material from touching the inner wall surface during passage of the molten material through the mold by flowing the mixture through the gap so as to avoid lubricant combustion, subsequent underdosing of the lubricant along the inner wall surface of the chill, and liquation and tacky area formation of the molten material being cast, whereby the molten material remains spaced apart from the inner wall surface.

Claim 27

A continuous casting annular mold, comprising: means for cooling an inner wall surface of a chill, the inner wall surface extending away from a superstructure of a continuous annular casting mold; means for directing a gas to flow under pressure parallel to the inner wall surface of the chill toward an area of transition of the overhang and the inner wall surface of the chill; means for directing a lubricant to mix with the flow of gas upstream of the transition so as to provide a mixture of the lubricant and gas under pressure in which the mixture flows in a direction parallel to the inner wall surface of the chill toward the transition; means for introducing at the transition of the overhang of the superstructure and the inner wall surface of the chill the mixture of the lubricant and gas under pressure; means for directing the mixture to flow before the mixture reaches the transition in a direction which is parallel to the inner wall surface of the chill and thereafter through a gap between the inner wall surface and a molten material to be cast; means for introducing the molten material to be cast adjacent to the overhang; and means for keeping the molten material from touching the inner wall surface during passage of the molten material through the mold by flowing the mixture through the gap so as to avoid lubricant combustion, subsequent underdosing of the lubricant along the inner wall surface of the chill, and liquation and tacky area formation of the molten material being cast, whereby the molten material remains spaced apart from the inner wall surface.

Claim 28

A continuous casting mold of claim 23, wherein said introducing a mixture means includes a gas supply line and a lubricant supply line which communicate with each other upstream of the transition relative to the direction of flow of the mixture to the transition.

Claim 29

A continuous casting mold of claim 23, wherein said means for introducing a mixture includes suctioning the mixture through the gap.