Locally changing the roll gap in the region of the strip edges of a rolled strip

Patent metadata

Field	Value
Publication number	US-11413669-B2
Application number	US-202016751547-A
Country	US
Kind code	B2
Filing date	Jan 24, 2020
Priority date	Jan 28, 2019
Publication date	Aug 16, 2022
Grant date	Aug 16, 2022

Abstract

Methods and apparatus for locally changing a roll gap in the region of the strip edges (10) of a rolled strip (1) in a rolling stand (2). The roll gap can be changed locally in the region of the strip edges (10) of the strip (1) during the hot rolling. Axial displacement of the working rollers (3, 4) in opposite directions is by a displacement distance s, where s is greater than or less than Δr/tan(α) and Δr indicates the wear of the running surface (8) in the radial direction (R) and α indicates the pitch angle of the conical portion (7) of the respective working roller (3, 4).

First claim

The invention claimed is:

1. A method for locally increasing a size of a roll gap in a region of strip edges of a rolled strip in a rolling stand, wherein the rolling stand comprises:
an upper working roller and a cooperating lower working roller, the rollers extending parallel to each other and defining a gap between the rollers, the rollers cooperating for passage of the rolled strip through the gap between the rollers;
each working roller having two opposite ends configured for rotational mounting of the working roller;
each working roller having, in a respective axial direction thereof, a conical portion followed by a running surface;
the upper working roller is oriented in an opposite axial direction to the lower working roller;
each working roller having a respective separate displacing device configured and operable for axially displacing the respective working roller;
the method comprising:
determining a radial wear Δr of the running surface of at least one of the working rollers in a radial direction thereof, and
hot rolling a rolled stock in the rolling stand through the gap between the rollers, and causing the radial extent of the running surface of at least one of the working rollers to decrease by Δr during the rolling, while
axially displacing the working rollers in opposite axial directions by a displacement distance

s
>

Δ
⁢

⁢
r

tan
⁡

(
α
)

,

where α indicates a pitch angle of the conical portion of the respective working roller.

2. A method for locally increasing a size of a roll gap in a region of strip edges of a rolled strip in a rolling stand, wherein the rolling stand comprises:
an upper working roller and a cooperating lower working roller, the rollers extending parallel to each other and defining a gap between the rollers, the rollers cooperating for passage of the rolled strip through the gap between the rollers;
each working roller having two opposite ends configured for rotational mounting of the working roller;
each working roller having, in a respective axial direction thereof a conical portion followed by a running surface;
the upper working roller is oriented in an opposite axial direction to the lower working roller;
each working roller having a respective separate displacing device for axially displacing the respective working roller;
the method comprising:
determining a rate of radial wear ({dot over (Δ)}r) of the running surface of at least one of the working rollers in a radial direction thereof, and
hot rolling a rolled stock in the rolling stand through the gap between the rollers, and causing the radial extent of the running surface of at least one of the working rollers to decrease at a rate of {dot over (Δ)}r during the rolling, while
axially displacing the working rollers in opposite axial directions at a displacement rate of

v
≡

s
.

>

Δ
⁢

⁢
r

.

tan
⁡

(
α
)

,

where α indicates a pitch angle of the conical portion of the respective working roller.

3. A method for locally reducing a size of a roll gap in a region of strip edges of a rolled strip in a rolling stand, wherein the rolling stand comprises:
an upper working roller and a cooperating lower working roller, the rollers extending parallel to each other and defining a gap between the rollers, the rollers cooperating for passage of the rolled strip through a gap between the rollers;
each working roller having two opposite ends configured for the rotational mounting of the working roller;
each working roller having in a respective axial direction thereof a conical portion followed by a running surface;
the upper working roller is oriented in an opposite axial direction to the lower working roller;
each working roller having a respective separate displacing device configured and operable for axially displacing the respective working roller;
the method comprising:
determining a radial wear Δr of the running surface of at least one of the working rollers in a radial direction thereof,
hot rolling a rolled stock in the rolling stand in the gap between the rollers, the radial extent of the running surface of at least one of the working rollers decreases by Δr during the rolling; and
axially displacing the working rollers in opposite axial directions by a displacement distance

s
<

Δ
⁢

⁢
r

tan
⁡

(
α
)

,

where α indicates a pitch angle of the conical portion of the respective working roller.

4. A method for locally reducing a size of a roll gap in a region of strip edges of a rolled strip in a rolling stand, wherein the rolling stand comprises:
an upper working roller and a cooperating lower working roller, each working roller having two opposite ends configured for the rotational mounting of the working roller
each working roller having, in a respective axial direction thereof, a conical portion followed by a running surface;
the upper working roller is oriented in an opposite axial direction to the lower working roller;
each working roller having a respective separate displacing device configured and operable for axially displacing the working respective roller;
the method comprising:
determining a rate of radial wear {dot over (Δ)}r of the running surface of at least one of the working rollers in a radial direction thereof, and
hot rolling a rolled stock in the rolling stand in the gap between the rollers, and causing the radial extent of the running surface of at least one of the working rollers to decrease at a rate of wear {dot over (Δ)}r during the rolling, while
axially displacing the working rollers in opposite axial directions at a displacement rate of

v
≡

s
.

<

Assignees

• Primetals Technologies Germany Gmbh

Inventors

• Dagner Johannes

Classifications

• B21B2027/022

  Rolls having tapered ends · CPC title

• B21B13/02

  with axes of rolls arranged horizontally · CPC title

• B21B2269/14

  Work rolls · CPC title

• B21B13/10

  all axes being arranged in one plane · CPC title

• B21B37/62 Primary

  by control of a hydraulic adjusting device · CPC title