Slab manufacturing method and control device

Patent metadata

Field	Value
Publication number	US-11858019-B2
Application number	US-201917286660-A
Country	US
Kind code	B2
Filing date	Oct 21, 2019
Priority date	Oct 22, 2018
Publication date	Jan 2, 2024
Grant date	Jan 2, 2024

Abstract

A slab manufacturing method in which casting drum housing screw-down system deformation characteristics which have been acquired prior to the start of slab casting and which indicate deformation characteristics of a housing configured to support a casting drum and deformation characteristics of a screw-down system configured to screw down the casting drum is used to calculate an estimated plate thickness at both end portions of a slab in a width direction thereof from Expression 1 ((estimated plate thickness on entry side of rolling mill)=(screw-down position of casting cylinder)+(elastic deformation of casting drum)+(casting drum housing screw-down system deformation)+(drum profile of casting drum)−(elastic deformation of casting drum at time of screw-down position zero-point adjustment)), an entry-side wedge ratio and an exit-side wedge ratio are calculated on the basis of the estimated plate thickness calculated from Expression 1.

First claim

The invention claimed is:

1. A slab manufacturing method for manufacturing a slab using a twin-drum type continuous casting device configured to cast a slab by solidifying a molten metal using a pair of rotating casting drums; and a rolling mill configured to roll the cast slab using a pair of work rolls, comprising:
calculating estimated plate thicknesses at both of end portions of the slab in a width direction from Expression 1:

(

e
⁢
stimated

⁢

plate
⁢

thickness
⁢

on
⁢

entry
⁢

side
⁢

of
⁢

rolling
⁢

mill

)

=

Expression
⁢

1

(

screw
-
down
⁢

postion
⁢

of
⁢

casting
⁢

cylinder

)

+

(

elastic
⁢

deformation
⁢

of
⁢

casting
⁢

drum

)

+

(

casting
⁢

drum
⁢

housing
⁢

screw
-
down
⁢

system
⁢

deformation

)

+

(

drum
⁢

profile
⁢

of
⁢

casting
⁢

drum

)

-

(

elastic
⁢

deformation
⁢

of
⁢

casting
⁢

drum
⁢

at
⁢

the
⁢

time
⁢

of
⁢

screw
-
down

position
⁢

zero
-
point
⁢

adjustment

)

using casting drum housing screw-down system deformation characteristics acquired prior to the start of slab casting indicating deformation characteristics of housings configured to support the casting drums and deformation characteristics of a screw-down system configured to screw down each of the casting drums;
calculating an entry-side wedge ratio indicating a ratio of an entry-side wedge which is a difference between plate thicknesses at both of the end portions on an entry side of the rolling mill to an entry-side plate thickness of the slab on the basis of the estimated plate thicknesses calculated from the Expression 1;
calculating an exit-side wedge ratio indicating a ratio of an exit-side wedge which is a difference between plate thicknesses at both of the end portions on an exit side of the rolling mill to an exit-side plate thickness of the slab; and
adjusting a screw-down position of the rolling mill so that a difference between the entry-side wedge ratio and the exit-side wedge ratio is within a prescribed range.

2. The slab manufacturing method according to claim 1 , wherein the exit-side plate thickness used for calculating the exit-side wedge ratio is estimated through Expression 2:

(

estimated
⁢

plate
⁢

thickness
⁢

on
⁢

exit
⁢

side
⁢

of
⁢

rolling
⁢

mill

)

=

Expression
⁢

2

(

screw
-
down
⁢

Assignees

• Nippon Steel Corp

Inventors

• Nikkuni Daisuke
• Shiraishi Toshiyuki
• Sadano Yutaka
• Miyazaki Masafumi

Classifications

• B21B1/04 Primary

  in a continuous process · CPC title

• B21B37/58 Primary

  Roll-force control; Roll-gap control {(B21B38/105 takes precedence)} · CPC title

• B22D11/06 Primary

  into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars · CPC title

• B22D11/12

  Accessories for subsequent treating or working cast stock in situ (rolling immediately subsequent to continuous casting B21B1/46, B21B13/22) · CPC title

• B21B1/00

  Metal-rolling methods or mills for making semi-finished products of solid or profiled cross-section (B21B17/00 - B21B23/00 take precedence; with respect to composition of material to be rolled B21B3/00; extending closed shapes of metal bands by simultaneous rolling at two or more zones B21B5/00; metal-rolling stands as units B21B13/00; continuous casting into moulds having walls formed by moving rolls B22D11/06); Sequence of operations in milling trains; Layout of rolling-mill plant, e.g. grouping of stands; Succession of passes or of sectional pass alternations · CPC title