JPS5923826A - Cooling method of metallic strip by cooling roll - Google Patents

Abstract

PURPOSE:To cool continuously and efficiently a high temp. metalllic strip without disturbance in its shape by specifying the fall rate of the critical temp. for each one piece of cooling rolls in said strip. CONSTITUTION:A high temp. metallic strip is run at a specified speed in contact with a cooling roll and is thus cooled. The flow of the refrigerant to be flowed in cooling rolls and rolls is set within the range where the fall rate DELTATSCR of the critical temp. for each one piece of the rolls is expressed as the related equation (the temp. in the strip before contact with the roll TS1, the temp. difference in temp. before and after the contact with the roll DELTATS). The high temp. metallic strip is continuously cooled by combining 1- plural pieces of such rolls. The generation of crease, buckling, etc. in the strip is virtually eliminated by the above-mentioned cooling method, and the commodity value is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a four-strip cooling method using a cooling roll, in which a high-temperature strip is brought into contact with the outer peripheral surface of a cooling roll through which a refrigerant is circulated, and the strip is cooled by running at a constant speed. .

The copper strip (metal strip) is heated to a predetermined annealing temperature in a continuous annealing furnace, soaked, and then heated to a hot metal temperature of 6.0
0 to b is metallurgically required, and the cooling method is as follows:
There are methods using a gas jet, a method using water spray, a method using fog, and a method using a cooling roll with refrigerant flowing inside.In the case of a gas jet, when the copper strip throughput □ increases, a gas jet is formed. The power required for this purpose increases significantly, causing loss of economic efficiency and making it impossible to plan the equipment.In addition, when water spray or fog is used, water comes into contact with the surface of the copper strip and the surface of the steel strip becomes oxidized. Therefore, it is necessary to clean the surface by rigorous washing, etc., which not only complicates the equipment, but also reduces the bondability of the steel plate surface. As a cooling method, it is said to be advantageous to wind a high depth metal strip around a cooling roll to form a contact state.

The cooling of the metal strip by the cooling roll is shown in Figure 1 (A
) As shown in (B), the rotating shaft (3) of the cooling roll (1), which is supported and rotated by a bearing (5), is fixed via a rotary joint) Refrigerant supply and discharge pipes (131 (11) are connected in series, and refrigerant is supplied to the chamber (6) of the cooling roll (1) through the supply and discharge pipes (131U 11 and the through hole of the rotating shaft (3)). The high-temperature metal strip (α) running at a predetermined constant speed is applied to the cooling rolls (1) (1,)... as shown in Figure 1 (B) K. They are placed in contact with each other and are cooled.

However, when water is used as the refrigerant flowing through the cooling roll in 7.11 for cooling the metal strip using the cold nozzle roll, the amount of water in the cooling roll is small and the temperature of the metal strip exceeds 100°C. Then, the refrigerant water boils in the cooling roll, and the amount of cooling in the width direction of the metal strip becomes uneven, and the temperature difference in the width direction that occurs in the metal strip causes the shape of the IJ tube to wrinkle, tear, etc. It becomes a defective product and the product value decreases by 4ti.
5. In addition, there is a large amount of refrigerant water in the cooling roll (even if it does not boil, the contact of the metal strip to the cooling roll is insufficient, unbalanced water cannot be avoided, and the transmission between the two is poor. Thermal ridge K1: 51.'c Since a difference of about 1:10 occurs, the winding angle (contact length) of the metal strip with respect to the cooling roll and the metal strip per cooling roll) The temperature drop of the IJ tube k When it becomes a dog, it becomes metal) I
There is a score of 1 if a phenomenon similar to the above occurs in the J-tube and the product value is lost.

The present invention was developed to eliminate the above-mentioned difficulty in the conventional metal strip cooling method using a cooling roll. In the cooling method, the above-mentioned Takako metal steel
The critical temperature drop ΔTSCR per roll in the IJ tube is set within the range of 1 by setting the cooling roll and the refrigerant in relation to the temperature Tsl before contact with the roll in the same strip and the temperature difference ΔTs before and after contact with the roll in the same strip.
1, and the high-temperature Kinzo strip is connected by the cooling roll, which has one or several strips combined.
It is characterized by the fact that the metal strip is cooled by cooling, and the main feature is that the metal strip is cooled by no contact with the refrigerant.
In the J-roll cooling method, the high temperature gold! (In relation to the temperature conditions of the strip, it is possible to avoid disturbances in the shape of the metal strip by specifying the critical temperature drop at the IJ tube.) The present invention provides a method for cooling metal slips.

The method of the present invention has the above-described structure, and in the method of cooling a metal strip using a cooling roll, the critical temperature of the high temperature metal strip per cooling roll is 1.
Let ΔTSCR be the temperature T81 of the same strip before contact with the same roll and the temperature difference ΔTs before and after contact with the same roll.
In connection with this, the high width metal strip is held within the area by setting a cooling roll and a refrigerant, and the wide metal strip is continuously cooled by one or more cold 7fl+ rolls, so that it does not come into contact with the outer circumferential surface of the cooling roll. The 44-degree difference in the width direction of the high-temperature metal strip that is run and cooled is extremely small, and the high-temperature metal strip has almost no wrinkles, wilting, etc., and can be cooled continuously and efficiently.
Product value can be significantly improved.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings. The method for cooling the gold strip in the embodiment of the present invention is carried out using the apparatus shown in FIGS. 1(A) and 2. As shown in FIG. 1(,A), the cooling roll (1) used for ) is supplied with a refrigerant into the chamber (6) (an overall cavity or an annular cavity in cross section), and the cooling roll (1) is cooled from inside by the refrigerant.
The liquid is discharged from the drain pipe 0υ through the through hole of the cooling roll ( ) and the rotary joint (4).
As shown in FIG. 1(B), one or more metal strips 11 are arranged at appropriate intervals, and as shown in the same figure, the metal strips (α) are wound on cooling rolls (11Kj, 9i at a constant angle). When approached and contacted, it runs at a constant speed and is cooled continuously.

In addition, the refrigerant flowing inside the cooling roll (1) is communicated from the refrigerant drain pipe (lυ) fixed by the rotary joint (4) to the same liquid supply pipe α (8) as shown in Fig. 2. The refrigerant is circulated through the refrigerant circulation path and sent from the drain pipe (11) to the storage tank (7) equipped with a level meter.
12') into the heat exchanger (9) to be cooled, and then flowed into the cooling roll m from the supply pipe (13) side, and the heat exchanger (9) Since the amount of cooling liquid in the cooling pipe U (g) can be adjusted by the flow rate adjustment valve 0α, the temperature of the refrigerant supplied into the cooling roll can be adjusted. In addition, when using water as a refrigerant, the heat exchanger (9), the storage tank (7), and the piping force between the storage tank (7) and the pump (8) are not necessarily required. Instead, refrigerant water can be supplied from a water supply source using a pump (8), and the drain pipe (fil) can be connected to a drainage pit, etc., and the refrigerant circulation path shown in FIG. is equipped with a replacement mechanism (not shown) for replacing refrigerants such as water, oil, molten salt liquid, etc.

The high brocade metal strip (a) to be cooled is brought into predetermined contact with an appropriate number of cooling rolls (1) arranged as shown in FIG. 1(B) in the cooling zone of the cooling process in the continuous heat treatment line. The cooling roll (1) is wrapped around the corner and runs at a constant speed of T91 in contact with the outer circumferential surface of the cooling roll (1) which is being rotated within a predetermined contact range and is cooled.

In addition to the above cooling, the wetness of the cooling roll (1) was measured using the same roll (1) of the IJ tube (a).
) is the temperature before contact with the roll (1), and Tsl is the temperature after contact with the same roll (1). If it is 32, then t<Ts2! According to history, 1. The IJ tube (a) is cooled by removing heat from it by the cooling roll. C,
What is important during this cooling is that the cooling roll (1) and the metal strip (σ) are in an ideal state, that is, when both are +
[The goal is to maintain a contact state with sufficient pressure uniformity in the J direction and the length direction within the contact angle, but in practice this cannot be expected and uneven contact tends to occur.
), which causes a difference in the amount of heat removed between the metal strips (ak) and causes a loss of product value. Regarding the critical hot water temperature drop ΔTSCH in the metal strip (α) per cooling roll (1) that does not cause any disturbance in the shape of the cooling roll (1), the following result was obtained. That is, the degree of deviation before roll contact of the metal strip (a) Ts1
The difference between the vorticity TS2 and the vorticity after roll contact is TSI TS2=
Assuming ΔTs (difference in groove depth before and after roll contact), temperature difference ΔTs before and after roll contact is JT6 = GK (T!3-
T1. , ) --(2 square, K soft r M
i medium and metal strip 1 (11 plt + ii pass rate (K
c(ll /lri'/"G) Tξ1&p,f'"N
Average preparation of 1 J tube of gold topping in 1 minute T, average IH degree of N refrigerant C (J), C refrigerant, roll diameter, pitch angle, metal strip speed IW, thickness, specific heat, specific heat Beast Q (constant determined by 2) L' (2/
It has been found that it can be broken down to the above formula.

Therefore, the equation +11 and equation (2) above, l'i',
is the formula (1) -'' and the formula (Z), that is, ``8CR<;ΔI11.3. ．． )) and 7f, the above equation (1) and +3i equation give the range of...
Samotoichi for each cooling roll (1) that can cool C'19 without disturbing the groove shape of the strip (σ).
rJil Mself (ΔTscI(t
'：t
+,; , changes, riiJ Mi,' is related to T3 TW in equation (2) and regulates Tw.
In relation to 81 and ΔTs, it becomes necessary to set Tw to 100° C. or higher.

Therefore, in order to correspond to the temperature conditions of the refrigerant, it is also possible to
It became necessary to use different refrigerants for the molten salt solution, and the following results were obtained through experiments.

Refrigerant temperature range Refrigerant gods Tw<100”
C: Water 50°C≦Tw≦300'C Oil 150'C≦TV/≦700'c Refrigerant and metal strip (a
) has been found to have an effect on the heat transfer rate between the cooling rolls (1) and the heat transfer coefficient with the refrigerant on the inner surface of the cooling roll (1), the shell thickness of the roll, the irregularities caused by the mechanical finish on the roll surface, and the metal. A gaseous substance exists in the gaps caused by unevenness due to the rolling finish of the strip! +! ! It is a function of the thermal conductivity and heat transfer coefficient of the 7I quality. According to experimental results, the heat transfer rate between the refrigerant and the metal strip (α) is determined by taking into account the material of the roll shell, the contact (wrap) angle, the roll surface roughness, etc. However, β is The contact (wrapping) angles a and b can be expressed by the constant equation (4) determined by the material of the roll shell, the 11 degree surface, the type of refrigerant, the thickness of the roll shell, the line speed, etc. , σ-66
40~15000 h=i~10 However, 36ro5≦aXb;515000 and 1
00×β<1800.

Furthermore, as a factor determining Δ゛rs, Tw, that is, the refrigerant r
You can change your quality. For this purpose, as shown in Fig. 2, an adjustable heat exchanger (9) is provided in the refrigerant flow path, and the refrigerant flow rate is adjusted to 6n to supply it into the cooling roll (1). The refrigerant can be set and controlled.

As mentioned above, when cooling a wide metal strip with a cooling roll, the cooling jJ flow setting as described above is applied so that the critical hot water temperature drop fjt per one cooling roll in the Takafuchi metal strip is within a specific range. By setting the type of refrigerant and temperature, etc., it is possible to improve efficiency without causing any disturbance in the shape of the metal strip (continuous cooling becomes H1 function, which significantly improves product value be able to.

Although the present invention has been described above with reference to embodiments, it goes without saying that the present invention is not limited only to such embodiments, and that modifications of each design dF may be made within the scope of the present invention without departing from the spirit of the present invention. L, Urumonode 4).

[Brief explanation of the drawing]

Figure 1 (N is a longitudinal cross-sectional view of a cooling roll for carrying out the method of the present invention, Figure 1 ([3) is a layout diagram of the cooling roll and metal strip in Figure 1 (A), and Figure 2 is a diagram showing the arrangement of the cooling roll and metal strips in Figure 1 (A)). 1 is a diagram of the refrigerant supply mechanism. 1: Cooling roll 6: Rotating shaft 4: Rotary joint 5: Bearing 6: Chamber 7: Storage tank 8: Pump
9: Heat exchanger 10: Flow; i control valve 11: Liquid pipe 16: Liquid supply pipe σ: Gold IIj 3 strip sub-agent patent attorney Okamoto ILJ 2 other people

Claims (1)

[Scope of Claims] In a cooling method in which a high-temperature metal strip is brought into contact with the outer circumferential surface of a cooling roll through which a refrigerant is circulated and cooled by running at a constant speed, The temperature drop ΔTSCR is maintained within the range of by setting the cooling roll and the refrigerant in relation to the temperature difference ΔTs before and after the roll contact with the strip, and the temperature difference ΔTs before the roll contact with the same strip, and the high temperature metal strip is A method for cooling a metal strip using cooling rolls, characterized in that the cooling rolls are continuously cooled by one or more of the cooling rolls.