ROLLING MILL AND TANDEM ROLLING MILL HAVING THE SAME

• US 20110023572A1
• Filed: 01/15/2009
• Published: 02/03/2011
• Est. Priority Date: 01/25/2008
• Status: Active Grant

• Current Assignee: Primetals Technologies Japan, Ltd. (Mitsubishi Heavy Industries, Ltd.)
• Original Assignee: Mitsubishi-Hitachi Metals Machinery Incorporated (Mitsubishi Heavy Industries, Ltd.)
• Inventors: Norikura, Takashi
• Granted Patent: US 8,607,609 B2
• Time in Patent Office: Days
• US Class Current: 72/224
• CPC Class Codes: B21B 13/145 Lateral support devices for rolls acting mainly in a direction parallel to the movement of the product
• CPC Class Codes: B21B 2013/028 Sixto, six-high stands
• CPC Class Codes: B21B 2261/06 Width
• CPC Class Codes: B21B 2267/06 Roll diameter
• CPC Class Codes: B21B 2267/28 Elastic moduli of rolls
• CPC Class Codes: B21B 27/021 Rolls for sheets or strips
• CPC Class Codes: B21B 3/02 Rolling special iron alloys , e.g. stainless steel

Abstract

A rolling mill, which can use work rolls of a smaller diameter for rolling a hard material and a thin strip material, and can decrease edge drops and improve surface gloss, is provided. For this purpose, a rolling mill, which includes upper and lower work rolls (2) as a pair for rolling a strip (1), upper and lower intermediate rolls (3) as a pair for supporting the upper and lower work rolls as the pair, and upper and lower back-up rolls (4) as a pair for supporting the upper and lower intermediate rolls as the pair, is configured such that the upper and lower work rolls as the pair are supported by a plurality of supporting bearings (8a to 8f and 9a to 9f) arranged vertically zigzag on an entry side in a rolling direction, and a plurality of supporting bearings (10a to 10f and 11a to 11f) arranged vertically zigzag on an delivery side in the rolling direction, at positions outward of a rollable strip width, and the plurality of supporting bearings lap over each other vertically.

Claims

1. A six-high rolling mill including upper and lower work rolls as a pair for rolling a metal strip, upper and lower intermediate rolls as a pair for supporting the work rolls, and upper and lower back-up rolls as a pair for supporting the upper and lower intermediate rolls as the pair, the six-high rolling mill having no supporting rolls inside a rollable strip width of the work rolls,

the six-high rolling mill comprising a plurality of supporting rollers or supporting bearings provided at predetermined spacings in a roll axis direction on both of an entry side and an delivery side on an operating side and a drive side outside the rollable strip width of the upper and lower work rolls as the pair such that the supporting rollers or supporting bearings are arranged vertically zigzag between the upper and lower work rolls as the pair.

2. The rolling mill according to claim 1, wherein

a minimum roll diameter of the work roll is intermediate between a minimum diameter upper limit Dmax1 and a minimum diameter lower limit Dmin1, and these parameters are expressed by the following equations:

minimum diameter upper limit Dmax1=D4max×

B/5^(1/4)

where D4max;

minimum diameter upper limit of conventional work roll with strip width of 1,300 mm;

380 mm

B;

strip width (mm)/1,300 mm

minimum diameter lower limit Dmin1=D4min×

B/5^(1/4)

where D4min;

minimum diameter lower limit of conventional work roll with strip width of 1,300 mm;

180 mm

3. The rolling mill according to claim 1, wherein

a material having a high modulus of longitudinal elasticity is used for the work roll, and

a minimum roll diameter of the work roll is intermediate between a minimum diameter upper limit Dmax2 and a minimum diameter lower limit Dmin2, and these parameters are expressed by the following equations:

minimum diameter upper limit Dmax2=D4max×

B/(5×

K)^(1/4)

where D4max;

minimum diameter upper limit of conventional work roll with strip width of 1,300 mm;

380 mm

;

strip width (mm)/1,300 mm

K;

ratio for modulus of longitudinal elasticity of high longitudinal modulus material to conventional material

(modulus of longitudinal elasticity of high longitudinal modulus material/modulus of longitudinal elasticity of conventional material (21,000 kg/mm²))

minimum diameter lower limit Dmin2=D4min×

B/(5×

K)^(1/4)

where D4min;

minimum diameter lower limit of conventional work roll with strip width of 1,300 mm;

180 mm

4. A tandem rolling mill including a plurality of rolling mill stands arranged therein, wherein

the rolling mill according to claim 1 is provided as at least one of the stands.

5. A tandem rolling mill including a plurality of rolling mill stands arranged therein, wherein

the rolling mill according to claim 2 is provided as at least one of the stands.

6. A tandem rolling mill including a plurality of rolling mill stands arranged therein, wherein

the rolling mill according to claim 3 is provided as at least one of the stands.