WO2006046459A1

WO2006046459A1 - Molten metal feed nozzle

Info

Publication number: WO2006046459A1
Application number: PCT/JP2005/019282
Authority: WO
Inventors: Hiroyuki Otsuka; Akihiko Kimatsuka; Shiro Osada; Hiroki Yoshizawa; Hisahiko Fukase; Rama Mahapatra; Peter Woodberry
Original assignee: Ishikawajima-Harima Heavy Industries Co., Ltd.
Priority date: 2004-10-27
Filing date: 2005-10-20
Publication date: 2006-05-04
Also published as: AU2005298039B2; EP1818120B1; US20090126895A1; CN101048247B; CN101048247A; AU2005298039A1; KR20070068440A; JP4720145B2; JP2006122933A; DE602005027603D1; EP1818120A1; KR100947756B1; EP1818120A4

Abstract

A molten metal feed nozzle, wherein an extension body (11) having a lower portion immersed in a molten metal sump and projected toward a side dam (2) so that the area of a stagnated part on the free liquid level of a molten metal can be eliminated is formed at the end thereof. The extension body (11) is formed in such a shape that a quadrangular pyramid is fallen sideways, and converged toward a point (P1) near the side dam (2). Since the nozzle replaces the area of the stagnated part on the free liquid level of the molten metal with the extension body (11) continued to the end of the nozzle to suppress the generation of unnecessary solidified shell, the solidified shell generated on the outer peripheral surface of cooling rolls (1) and forming a strip does not hold the unnecessary solidified shell as foreign matter, and the breakage of the strip resulting from an increase in a clearance between the rolls can be avoided.

Description

Specification

Molten metal supply nozzle

Technical field

[0001] The present invention relates to a molten metal supply nozzle incorporated in a twin roll forging machine.

Background art

FIG. 1 shows an example of a twin-roll forging machine, which includes a pair of cooling holes 1 arranged horizontally and a pair of side weirs 2 attached to the cooling roll 1.

[0003] The cooling roll 1 is configured such that cooling water flows through the roll 1 and the roll gap G can be adjusted in accordance with the thickness of the strip 3 to be produced.

[0004] In addition, the rotation direction and speed of the cooling roll 1 are set so that each outer peripheral surface moves from the upper side toward the roll gap G at a constant speed.

[0005] One side weir 2 is pressed so as to be in surface contact with one end of each cooling roll 1, and the other side weir 2 is pressed so as to be in surface contact with the other end of each cooling roll 1, In a space surrounded on all sides by the side weir 2 and the cooling roll 1, a molten metal supply nozzle made of a refractory material is arranged so as to be located immediately above the roll gap G.

[0006] The molten metal supply nozzle has an elongated nozzle trough 5 that is open to receive the molten metal 4, and penetrates from the nozzle trough 5 toward the outer peripheral surface of the cooling roll 1 at a portion near the lower end of the longitudinal side wall. Multiple openings are formed so that the openings 6 are aligned along the axis of the cooling roll 1. When the molten metal 4 is poured into the nozzle trough 5, a molten metal pool 7 that contacts the outer peripheral surface of the cooling roll 1 is formed above the gap G. The

That is, when the cooling roll 1 is removed by removing the cooling roll 1 by circulation of the cooling water and the cooling roll 1 is rotated by rotating the cooling roll 1, the molten metal 4 is solidified on the outer peripheral surface of the cooling roll 1 and between the rolls. Strip 3 is sent downward from gap G.

[0008] In addition, since the wear of the cooling roll 1 sliding portion of the side weir 2 progresses in proportion to the accumulated operation time, the pressing force of the side weir 2 against the cooling roll 1 is gradually increased, and the molten metal 4 is caused between these members. Do not leak.

[0009] The molten metal supply nozzle incorporated in the twin roll forging machine has a nozzle end facing the side weir 2 There are those in contact (for example, see Patent Document 1) and those in which the nozzle ends are separated from the side weir 2 and face each other in parallel (for example, see Patent Document 2).

Patent Document 1: JP-A 62-45456

Patent Document 2: JP-A-6-114505

Disclosure of the invention

Problems to be solved by the invention

[0010] However, when the structure as in Patent Document 1 is adopted, the dimension in the longitudinal direction of the molten metal supply nozzle remains unchanged. Leakage of the molten metal 4 cannot be suppressed simply by increasing the pressing force of the side weir 2 against the rod 1.

[0011] Further, when the structure as in Patent Document 2 is adopted, the side weirs facing each other in parallel as compared between the melt nozzle longitudinal side wall surface 8 and the cooling roll 1 as shown in FIG. Between the molten metal reservoir surface 9 and the molten metal nozzle end wall surface 10, the flow velocity distribution on the molten metal 4 free liquid surface tends to be lower, especially from the molten metal nozzle end wall surface 10 to the side weir molten metal reservoir surface 9. The point where the roll gap center line L intersects The range A where the molten metal 4 tends to stagnate toward the PO

[0012] In the range A of the starch, an event that the temperature of the molten metal 4 decreases due to radiant heat transfer occurs, and unnecessary solidified shells are generated on the free liquid surface of the molten metal 4 and the wall surface 10 of the molten metal nozzle.

[0013] Further, when the solidified shell generated on the outer peripheral surface of each cooling roll 1 sandwiches the above-described unnecessary solidified shell as a foreign matter, a shape defect that locally thickens the strip 3 occurs. The roll gap G is pushed and expanded by the portion of the strip 3 where the foreign matter is sandwiched, and the strip 3 may break due to reduced cooling efficiency and recuperation from the molten metal 4.

[0014] The present invention has been made in view of the above-described circumstances, and an object thereof is to provide a molten metal supply nozzle capable of avoiding breakage of a strip! Speak.

Means for solving the problem

[0015] In order to achieve the above object, the present invention provides a molten metal supply nozzle that is located above a roll gap of a twin roll forging machine and that has an end portion separated from a side dam key, and is connected to the nozzle end portion. An extension body that protrudes toward the side weir so that the range of stagnation on the free surface of the molten metal disappears Provided.

[0016] In the present invention, the extension body eliminates the stagnation range of the free surface of the molten metal, prevents a decrease in the temperature of the molten metal due to radiant heat transfer, and suppresses the formation of unnecessary solidified shells.

The invention's effect

[0017] According to the molten metal supply nozzle of the present invention, the following excellent effects can be obtained.

[0018] (1) The extension body prevents the temperature of the molten metal near the side weir from lowering and suppresses the formation of solidified shells on the free surface of the molten metal. Therefore, it is possible to avoid the breakage of the strip due to the expansion of the roll gap.

(2) When the extension body is converged toward the side weir and the volume of the extension body is gradually reduced, heat transfer from the molten metal to the extension body is reduced, and the The temperature drop of the molten metal can be effectively prevented.

Brief Description of Drawings

FIG. 1 is a conceptual diagram showing an example of a twin roll forging machine.

FIG. 2 is a conceptual diagram showing the flow velocity distribution on the free surface of the melt near the melt supply nozzle of FIG.

FIG. 3 is a partial perspective view showing a state where the first embodiment of the molten metal supply nozzle of the present invention is looked up from the lower side.

FIG. 4 is a conceptual diagram showing a state in which the molten metal supply nozzle of FIG. 3 is viewed in the cooling roll axis direction.

FIG. 5 is a conceptual diagram showing a state in which the molten metal supply nozzle of FIG. 3 is viewed in the tangential direction of the cooling roll.

FIG. 6 is a conceptual diagram showing the flow velocity distribution on the free surface of the melt near the melt supply nozzle of FIG.

FIG. 7 is a partial perspective view showing a state where the second embodiment of the molten metal supply nozzle of the present invention is looked up from the lower side.

FIG. 8 is a conceptual diagram showing a state in which the molten metal supply nozzle of FIG. 7 is viewed in the cooling roll axis direction.

FIG. 9 is a partial perspective view showing the third embodiment of the molten metal supply nozzle of the present invention looking up from the lower side.

FIG. 10 is a conceptual diagram showing a state in which the molten metal supply nozzle of FIG. 9 is viewed in the cooling roll axis direction. Explanation of symbols

[0021] 2-side weir

7 Molten pool

11, 12, 13 Extension

A range

G Roll gap

P1 point

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIGS. 3 to 6 show a first embodiment of the molten metal supply nozzle of the present invention. In the figure, the same reference numerals as those in FIGS. 1 and 2 denote the same parts.

[0024] An extension body 11 is provided at the end of the nozzle so that the lower portion is immersed in the molten metal reservoir 7 and protrudes toward the side weir 2 so that the molten metal 4 free liquid level stagnation range A (see Fig. 2) disappears. ing.

[0025] The extension 11 is shaped like a quadrangular pyramid lying sideways and converges toward a point P1 close to the side weir 2.

[0026] In the twin roll forging machine incorporating this molten metal supply nozzle, the range A of the stagnation of the molten metal 4 free liquid surface is replaced with the extension 11 connected to the end of the nozzle, thereby suppressing the formation of unnecessary solidified shells. The solidified shell that is generated on the outer peripheral surface of the cooling roll 1 and does not require the solidified shell forming the strip 3 is not sandwiched as a foreign substance, and the breakage of the strip 3 due to the expansion of the roll gap G can be avoided.

In addition to this, since the volume of the extension 11 is gradually reduced toward the side weir 2, heat transfer from the melt 4 to the extension 11 is reduced, and the melt 4 near the side weir 2 is reduced. Therefore, an unnecessary solidified shell is not generated on the side weir 2.

FIGS. 7 and 8 show a second embodiment of the molten metal supply nozzle of the present invention. In the figure, the portions denoted by the same reference numerals as those in FIGS. 3 to 6 represent the same thing.

[0029] An extension body 12 is provided at the end of the nozzle so that the lower portion is immersed in the molten metal reservoir 7 and protrudes toward the side weir 2 so that the molten metal 4 free liquid surface stagnation range A (see Fig. 2) disappears. ing. [0030] The extension body 12 has a wedge-like shape and converges toward a horizontal line segment connecting the points P2-P3 close to the side weir 2.

[0031] In the twin roll forging machine incorporating the molten metal supply nozzle, the range 4 of the molten metal 4 free liquid surface is replaced with the extension 12 connected to the end of the nozzle to suppress the formation of unnecessary solidified shells. The solidified shell that is generated on the outer peripheral surface of the cooling roll 1 and does not require the solidified shell forming the strip 3 is not sandwiched as a foreign substance, and the breakage of the strip 3 due to the expansion of the roll gap G can be avoided.

In addition to this, the volume of the extension 12 is gradually reduced toward the side weir 2, so that the heat transfer to the molten metal 4 (see FIG. 6) force extension 12 is reduced, and the side weir 2 The temperature drop of the molten metal 4 in the vicinity can be effectively prevented, and unnecessary solidified shells are not generated on the side weir 2.

FIG. 9 and FIG. 10 show a third embodiment of the molten metal supply nozzle of the present invention. In the figure, the parts denoted by the same reference numerals as in FIGS. 3 to 7 represent the same thing.

[0034] An extension 13 is provided at the end of the nozzle so that the lower part is immersed in the molten metal reservoir 7 and protrudes toward the side weir 2 so that the molten metal 4 free liquid level range A (see Fig. 2) disappears. ing.

[0035] The extension 13 is shaped like a tapered square pole lying sideways, and the point near the side weir 2 P2

-P3-P4— Focuses toward the vertical plane connecting P5.

[0036] In the twin roll forging machine incorporating this molten metal supply nozzle, the range A of the stagnation of the molten metal 4 free liquid surface is replaced with the extension 13 connected to the end of the nozzle to suppress the formation of unnecessary solidified shells. The solidified shell that is generated on the outer peripheral surface of the cooling roll 1 and does not require the solidified shell forming the strip 3 is not sandwiched as a foreign substance, and the breakage of the strip 3 due to the expansion of the roll gap G can be avoided.

[0037] The heat transfer from the molten metal 4 (see Fig. 6) to the extension 13 is greater than that in the first and second embodiments described above, The third embodiment is easier.

It should be noted that the melt supply nozzle of the present invention is not limited only to the above-described embodiments, and it is needless to say that changes can be made without departing from the gist of the present invention.

Industrial applicability

[0039] The molten metal supply nozzle of the present invention is applied to manufacture of various metal strips including steel. You can do it.

Claims

The scope of the claims

[1] A melt supply nozzle that is located above the roll gap of the twin-roll forging machine and that is separated from the end by the side weir force. A molten metal supply nozzle provided with an extending body that protrudes so that the range disappears.

[2] The molten metal supply nozzle according to claim 1, wherein the shape of the extension body is converged toward the side weir.

[3] The molten metal supply nozzle according to claim 1, wherein the shape of the extension body is converged toward one point near the side weir.