CN1026957C - Horizontal continuous casting method for metal wire stock - Google Patents

Abstract

The present invention provides a horizontal continuous casting method for metal wire stocks, which comprises the following steps: molten steel or master alloy is put in a pouring box which is provided with a medium frequency heating device; the temperature of the molten steel is controlled at 50 to 150 DEG C larger than the melting point; a crystallizer adopts a way that the crystallizer is cooled by feeding water from the back end so that the outlet temperature of casting wires is less than 500 DEG C; blank drawing is carried out to the casting wires cooled and solidified by the crystallizer through a blank drawing machine according to a technique curve of drawing, pushing and stopping, and the drawn casting wires are fine treated into stocks after being cut by a cutter. The present invention is suitable for producing high alloy stocks which are difficultly deformed, and the diameter of the high alloy stocks is from 3 to 15mm.

Description

Horizontal continuous casting method for metal wire stock

The invention belongs to the continuous casting of metal technical field.Be applicable to that mainly producing diameter is the high alloy wire rod that is difficult to be out of shape of 3～15mm.

Some high alloys are owing to intensity, hardness height, and room temperature and high-temp plastic are poor, and the distortion difficulty adopts common forging, roll process to be shaped, and then lumber recovery is very low, the cost height.For this reason, the country of some advanced technology has successively developed the wire horizontal continuous casting technology, produces the high-alloy wire section product of difficult distortion.

The metal wire rod horizontal continuous casting technology belongs to the new and high technology that the eighties grows up, and mainly produces the high alloy wire rod by horizontal continuous casting method.Its concrete technical process is: molten steel or foundry alloy are put into tundish, the boiling water mouth is connected with crystallizer at the bottom of the tundish bag, the crystallizer horizontal positioned, molten steel carries out throwing by drawing device after crystallizer solidifies, the throwing parameter is by computer control, the wire rod that casts out can directly use (" Stahlu Eisen " 106(1986), Nr.1, P5～12 after finishing, shearing; " Ironmaking and steelmaking " 1991, Vol.18, No2)

There is following shortcoming in said method:

＜1〉casting silk outlet temperature height causes surface oxidation, influence casting yarn quality, particularly surface quality.

＜2〉the crystallizer cooling effect is poor, and casting silk solidified shell is thinner, and easy fracture of wire influences production efficiency in process of billet withdrawal.

＜3〉crystallizer inwall tapering is big, allows air enter easily, causes the solidified shell surface oxidation.

For above-mentioned reasons, cause casting silk (wire rod) surface quality of being produced poor, production efficiency is low.

The object of the present invention is to provide a kind of new high alloy wire rod horizontal continuous casting method, but utilize the not only high alloy wire rod of the difficult distortion of direct forming of this method, and not oxidation of wire surface, secondary operations such as cold-drawn can directly be used or carry out to surface-brightening.

According to above-mentioned purpose, major technique measure of the present invention comprises: the molten steel temperature before the 1. strict control continuous casting, and avoid molten steel overheated, the formation and the line base core heat that influence solidified shell return the surface and cause blemish and oxidation; 2. crystallizer adopts the rear end water intake mode, avoids forming air film, strengthens cooling effect; The mean level continuous casting adopts the front end water intake mode, because the mould temperature height easily produces air film, influences cooling effect; 3. reduce crystallizer inwall tapering, avoid air to enter and cause the solidified shell surface oxidation; 4. control suitable casting speed, after the assurance molten steel solidified in crystallizer, surface temperature is no more than common heavy alloyed oxidizing temperature, and was too fast because of casting speed, and the casting silk surface temperature that goes out crystallizer is then high, causes surface oxidation; 5. the throwing system adopts the DC torque unit can control the process of billet withdrawal acceleration effectively.

The technological equipment schematic diagram that high alloy wire rod horizontal continuous casting method of the present invention is adopted as shown in Figure 1.

In the accompanying drawing 1,1 is tundish, and 2 is crystallizer, and 3 is guide roller, and 4 is control system, and 5 is Blank drawing machine, and 6 is roller-way, and 7 is cutter, and 8 are the finishing system.

Smelting furnace melting molten steel → tundish (adjustment temperature) → crystallizer solidifies → Blank drawing machine throwing-finishing.

Concrete technical process and parameter are as follows:

Molten steel or foundry alloy by the smelting furnace melting enter the tundish of being with intermediate frequency induction heating device, by induction heating apparatus, adjust the interior molten steel temperature of tundish and are incubated, and the assurance liquid steel temperature is stablized; Molten steel temperature is higher than fusing point and is advisable for 50～150 ℃ to be controlled at; Tundish is connected with crystallizer by the bag mouth of a river, the end, and molten steel enters crystallizer by the mouth of a river.For preventing molten steel oxidation, tundish places in the closed chamber, and adopts inert gas shielding.

Crystallizer inwall tapering is 1/1000, the crystallizer horizontal positioned, and its cooling system adopts the rear end water inlet type of cooling, prevents to form air film, strengthens cooling effect, so that the intensity of cooling of reasonable crystallization control device increases molten steel overheat, guarantees casting silk surface quality.By the cooling of water-cooling system, the molten steel that enters crystallizer is solidified gradually, forms the casting silk.

The casting silk that has solidified carries out throwing by Blank drawing machine according to the process curve of drawing-pushing away shown in the accompanying drawing 2-stop, casting speed is controlled at 2～6 meters/minute and is advisable, frequency of billet withdrawal is 150～200 times/minute, make the surface temperature after molten steel solidifies in crystallizer be no more than 500 ℃, promptly be no more than general heavy alloyed oxidizing temperature, guarantee the not oxidation of surface of casting silk.

The throwing system is made up of dc torque motor, pulse width modulated power supply and computer control system three parts, and whole throwing system finishes throwing in the mode that pushes away, draws, stops.The course of work of throwing system is: send the analog signal of dragging the base action by computer, analog signal converts electric impulse signal to through D/A, and the pulsewidth power supply is exported the signal of telecommunication by electric impulse signal to torque motor, and torque-motor is by signal of telecommunication action and finish throwing.

The wire rod of pulling out through roller-way, enters cutter, by required length specification, is cut into pieces, and enters finishing machine subsequently and carries out finishing, becomes a useful person.

Compared with prior art, major advantage of the present invention is that casting silk surface quality is good, and surface-brightening does not have the indentation of scuffing etc., simultaneously, because casting silk intensity of cooling is big, has improved the precision of casting silk, has reduced ovality, has increased the compactness of casting silk.

Description of drawings

Accompanying drawing 1 is the technological equipment schematic flow sheet of high alloy wire rod horizontal continuous casting method of the present invention.

Accompanying drawing 2 is high alloy wire rod horizontal casting billet withdrawal curve figure of the present invention.

In the accompanying drawing 2, abscissa is time t, and ordinate is casting speed n, and 9 is positive pulling rate degree, and 10 for just drawing the time, and 11 are the anti-speed that pushes away, and 12 push away the time for counter, and 13 is the dead time.

Embodiment

According to method of the present invention, having cast diameter on high alloy wire rod horizontal casting device continuously is the wire rod of CoCrW, NiCrCoMo, NiCrMoW, FeNiCrAl, 1Cr18Ni9Ti and the six kinds of alloys of OCr25Ni35Ti of φ 3～10mm.The technological parameter of casting process is as shown in table 1.To the wire rod that is cast out, except that the check surface quality, also carried out welding performance test, its result has all listed table 2 in.

The technological parameter of table 1 embodiment wire horizontal continuous casting

Technological parameter fusing point molten steel Wen Zhusi goes out crystallizer throwing speed throwing frequently

Surface temperature degree rate during alloy species

℃ the degree ℃ ℃ rice/gradation/minute

CoCrW 1400 1460 380 3.5 160

NiCrCoMo 1430 1520 400 3.7 160

NiCrMoW 1420 1520 400 4.0 160

FeNiCrAL 1480 1570 350 3.0 160

1Cr

NiTi 1410 1550 370 3.5 170

Cr ₂₅Ni

Ti 1405 1540 390 3.5 160

The surface quality and the physical property of table 2 embodiment continuous casting wire rod

Alloy wire diameter surface quality welding performance

mm

CoCrW 3-6 light zero defect weld metal does not have gas, is mingled with, function admirable

NiCrCoMo 8 bright zero defect weld metals do not have gas, are mingled with, function admirable

NiCrMoW 5 bright zero defect weld metals do not have gas, are mingled with, function admirable

FeNiCrAL 5 bright zero defect weld metals do not have gas, are mingled with, function admirable

1Cr Ni ₉Ti 4.5 bright zero defect weld metals do not have gas, are mingled with, function admirable

OCr ₂₅Ni

Ti 5 bright zero defect weld metals do not have gas, are mingled with, function admirable

Claims (2)

1, a kind of high alloy wire rod horizontal continuous casting method, its technical process is: molten steel or foundry alloy are put into tundish, molten steel mouth of a river at the bottom of the tundish bag flows into crystallizer, the crystallizer horizontal positioned, and use water cooling, the molten steel that enters crystallizer is solidified gradually, form the casting silk, the casting silk that has solidified by Blank drawing machine by draw-push away-stop work the skill curve carry out throwing, the casting silk (wire rod) of pulling out enters cutter through roller-way, is cut into pieces by required size, enters finishing machine subsequently and carries out finishing, become finished product, it is characterized in that:

A, middle band frequency heating device;

B, molten steel temperature are controlled at and are higher than 50～150 ℃ of fusing points;

C, crystallizer cooling system adopt the type of cooling that enters from the rear end;

D, crystallizer inwall tapering are 1/1000;

2～6 meters/minute of E, casting speeds;

F, casting silk outlet temperature are less than 500 ℃;

G, throwing system are made up of dc torque motor, pulse width modulated power supply and computer;

H, tundish place in the closed chamber, and adopt inert gas shielding.

2, method according to claim 1, when it is characterized in that throwing, frequency of billet withdrawal is 150～200 times/minute.

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