US4106318A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for rolling metallic material
Assignee: Nippon Steel Corp
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Filing: 1977-01-17
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Granted: 1978-08-15
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Expires: 1997-01-17
Abstract
Abstract In the rolling of metallic material by using a rolling mill having a working roll for each surface of the workpiece reduced and having the shafts fixed with respect to movement in the direction of travel of the workpiece, the workpiece is rolled at such a high reduction rate in cross-sectional area that the contact angle theta between the working roll and the workpiece can have a value of >/= tan-1 mu ( mu being the coefficient of friction between the working roll and the workpiece), and the rolling operation is carried out by pushing the workpiece between the working rolls, so that a neutral point of relative movements between the rods and the workpiece wire remain within the surface along which the working roll and the workpiece contact each other. The rolling apparatus has a device to push the workpiece between the working rolls and a rolling mill or rolling mills of high reduction capacity to roll the thus pushed workpiece at a high reduction rate of the cross-sectional area, whereby there can be rolled strip, bar, wire rod shape, beam blank or the like in a limited number of passes.
Inventors
- 👤 Samon Yanagimoto
- 👤 Minoru Kawaharada
- 👤 Shuji Nagata
- 👤 Fujimasa Koyama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:43
CPC Classifications
B; B21; B21B; B21B1/00; B21B1/08; B21B1/088; B21B1/02; B21B1/026; B21B1/22; B21B1/24
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
326 words
A method of rolling a steel workpiece by using a rolling mill having opposed working rolls in a fixed position relative to the direction of travel of the workpiece and at a fixed spacing from each other, which method comprises rolling the workpiece between the working rolls while driving said rolls and continuously exerting on the workpiece a force in the direction of movement of the workpiece through the rolling mill in addition to the force exerted in the direction of rolling by the working rolls within the surface of contact of the working rolls and the workpiece and which additional force in the direction of movement of the workpiece is less than that necessary to stress the workpiece beyond its yield point under the conditions of rolling and having a value σ p × A where A is the cross-sectional area of the workpiece and σ p is the additional exerted force per unit area of the workpiece and is represented by: ##EQU9## where: K: Yield stress (kg/mm 2 ) of the workpiece at the rolling temperature θ: Contact angle of the working roll (rad) a: Constant b: Constant C 1 : constant μ: Coefficient of friction between the working roll and the workpiece μ = [C 2 (1.05 - 0.0005.T) - 0.056· V R ] C 3 C 2 : constant determined according to the material of the working roll; 1.0 in the case of a forged steel roll; 0.8 in the case of a cast steel roll C 3 : constant determined according to the roll lubrication = 1 ˜ 0.1 V r : rolling speed (m/sec) T: rolling temperature (°C) whereby an elongation of the workpiece is produced which is much greater than the arithmetic sum of the elongation which would be produced by the driven working rolls alone and the elongation produced by the force in the direction of movement of the workpiece alone for moving the workpiece through non-driven rolls.
Claim 2
Independent Claim
326 words
A method of rolling a steel workpiece by using a rolling mill having opposed working rolls in a fixed position relative to the direction of travel of the workpiece and at a fixed spacing from each other, which method comprises rolling the workpiece between the working rolls while driving said rolls and continuously exerting on the workpiece a force in the direction of movement of the workpiece through the rolling mill in addition to the force exerted in the direction of rolling by the working rolls within the surface of contact of the working rolls and the workpiece and which additional force in the direction of movement of the workpiece is less than that necessary to stress the workpiece beyond its yield point under the conditions of rolling and having a value σ p × A where A is the cross-sectional area of the workpiece and σ p is the additional exerted force per unit area of the workpiece and is represented by: ##EQU9## where: K: Yield stress (kg/mm 2 ) of the workpiece at the rolling temperature θ: Contact angle of the working roll (rad) a: Constant b: Constant C 1 : constant μ: Coefficient of friction between the working roll and the workpiece μ = [C 2 (1.05 - 0.0005.T) - 0.056· V R ] C 3 C 2 : constant determined according to the material of the working roll; 1.0 in the case of a forged steel roll; 0.8 in the case of a cast steel roll C 3 : constant determined according to the roll lubrication = 1 ˜ 0.1 V r : rolling speed (m/sec) T: rolling temperature (°C) whereby an elongation of the workpiece is produced which is much greater than the arithmetic sum of the elongation which would be produced by the driven working rolls alone and the elongation produced by the force in the direction of movement of the workpiece alone for moving the workpiece through non-driven rolls.
Claim 3
Dependent Claim
28 words
The rolling method mentioned in claim 1, wherein said workpiece is a steel bar or wire rod, and said reduction rate of the cross-sectional area more than 30%.
Claim 4
Dependent Claim
24 words
A method of rolling a workpiece as claimed in claim 1 in which the step of exerting the additional force comprises pushing the workpiece.
Claim 5
Dependent Claim
19 words
A method as claimed in claim 3 in which the workpiece is pushed at the end of the workpiece.
Claim 6
Dependent Claim
39 words
The rolling method mentioned in claim 1, further comprising adjusting the reduction rate in cross-sectional area and the pushing force to control the width of the workpiece, whereby the workpiece can be rolled into the product of required dimensions.
Claim 7
Dependent Claim
89 words
The rolling method mentioned in claim 5, wherein said workpiece is steel plate, and said pushing force is so adjusted that the compressive stress caused by said pushing force has a value σ p and said reduction rate η represented by: ##EQU10## where: a = dη + f b : constant = 0.1 ˜ 2.5 c : constant = 0.5 ˜ 1.5 d : constant = 0.9 1.2 f : constant = 0.2 0.4 n : constant = 1.5 2.5 , thereby controlling the lateral spreading of said plate.
Claim 8
Dependent Claim
107 words
The rolling method mentioned in claim 5, wherein said workpiece is a flanged steel shape, and said pushing force is so adjusted that the compressive stress caused by said pushing force has a value σp represented by: ##EQU11## where: Ho : thickness of the workpiece before rolled Bo : width of the workpiece before rolled H 1 : desired flange width B : web width tw : web thickness Bw : width of web inside ##EQU12## a : constant = 0.5 ˜ 6.0 b : constant = -0.1 ˜ -6.0 d : constant = 1 ˜ 4 ##EQU13## , whereby controlling the lateral spreading of said flange.
Claim 9
Dependent Claim
52 words
The rolling method mentioned in claim 1, in which said additional force comprises both a pushing and a pulling force, said pulling force pulling said workpiece on the outlet side of the rolling mill and adjusting said pulling force together with said pushing force, thereby controlling the lateral spreading of the workpiece.
Claim 10
Dependent Claim
154 words
The rolling method mentioned in claim 8, wherein said workpiece is steel plate; and said pushing force and said pulling force are so adjusted that the compressive stress caused by said pushing force has a value σp represented by: ##EQU14## where: a = a + f b : constant = 0.1 ˜ 2.5 c : constant = 0.5 ˜ 1.5 d : constant = 0.9 ˜ 1.2 f : constant = 0.2 ˜ 0.4 η: web reduction rate = (Ho - tw/Ho) n : constant = 1.5 ˜ 2.5 , and the tensile stress caused by said pulling force has a value σt represented by: ##EQU15## , where: Bo : width of the workpiece before rolled B : width of the workpiece of the rolled (B/Bo).sub.σp = 0 : lateral spreading rate at tensile stress σt = 0 g : constant = -0.05 ˜ -0.8 , thereby controlling the lateral spreading of said plate.
Claim 11
Dependent Claim
179 words
The rolling method mentioned in claim 8, wherein said workpiece is a flanged steel shape; and said pushing force and said pulling force are so adjusted that the compressive stress caused by said pushing force has a value σp represented by: ##EQU16## where: ##EQU17## a 1 : constant = 0.5 ˜ 6.0 b 1 : constant = -0.1 ˜ -6.0 d : constant = 1 ˜ 4 η : web reduction rate = (Ho - tw/Ho) Ho : thickness of the workpiece before rolled Bo : width of the workpiece before rolled H 1 : desired flange width B : web width tw : web thickness Bw : width of web inside , and the tensile stress caused by said pulling force has a value Ot represented by: ##EQU18## , where K : yield stress of the workpiece at the rolling temperature Ho : desired flange width H 1 : desired flange width (H 1 /Ho).sub.σt = 0 : lateral spreading rate of flange at tensile stress σt = 0 , thereby controlling the lateral spreading of said flange,
Claim 12
Dependent Claim
160 words
The rolling method claimed in claim 8, wherein the rolling mill has a first pair of rolls, a second pair of rolls and a third pair of rolls, said pairs of rolls being in tandem, and the pushing force is exerted on the workpiece by controlling the first pair of rolls and the second pair of rolls so that the workpiece speed at the outlet of the first pair of rolls is faster than that at the inlet of the second pair of rolls and the pulling force is exerted on the workpiece by controlling the surface speeds of the working rolls of the second pair of rolls and the third pair of rolls so that the workpiece speed at the inlet of the third pair of rolls is faster than at the outlet of the second pair of rolls and the width of the workpiece is controlled by adjusting the magnitude of the pushing force and the pulling force.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-08-14 | 1982-02-13 | 1982-08-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-08-14 | 1986-02-13 | 1986-08-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-08-14 | 1990-02-13 | 1990-08-15 | $7700.00 | Window Closed / Lapsed |