JPS59116384A - Drying method of edge part of steel strip - Google Patents

Abstract

PURPOSE:To remove thoroughly a very small amt. of water sticking on the edges of a steel strip and to prevent the deterioration in the quality of the steel strip by heating locally the end edge parts of the steel strip after drying the top and bottom surfaces of the steel strip with hot wind then drying the strip under blasting of air in a drying stage after washing in a treatment line for the steel strip. CONSTITUTION:A local heater, such as an induction heating coil 9 or the like, for drying the very small amt. of the water sticking on the end edges of a steel strip 10 is installed in the end edge parts of the strip 10 in addition to a dryer 11 for drying the top and bottom surfaces of said strip, in a washing and drying stage in a treatment line for the steel strip. Only the end edges of the steel strip are heated by the current induced from said novel device 12 to evaporate the water sticking thereon. A blast nozzle 5a and a blast header 6a are further provided to blast air only to the end edges and the vapor pressure of the atmosphere is decreased to evaporate the water in a short time. The productivity of the treatment line for the steel strip is improved by the above-mentioned method.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for drying a cold rolled steel strip after the rolling or surface treatment surface 10 is cleaned in a finish-F rolling line or a surface treatment line.

In finish rolling lines for cold rolled steel strips (e.g. dry skin pass rolling lines) or surface treatment lines such as painting and plating, dust, oil stains, or oxidation are removed from the surface of the copper strip prior to finishing. Two cleaning steps will be installed to remove S. In this cleaning step 1, as shown in FIG. 1, the copper strip 10 is sequentially cleaned through the steps of a cleaning tank 1, a washing tank 1, a washing tank 2, a squeezing roll 3, and a drying device 4.

The present invention relates to the drying process.

Conventionally, this drying method involves blowing high-speed hot air (approximately 70°C to 90°C) vertically onto the surface of the running copper strip 10 from below using a blowing nozzle 5, as shown in Fig. 2. Common methods of drying include drying, evaporation, and blowing by physical force.

However, in this conventional drying method, the third
As shown in the figure, it is impossible to completely dry and remove even the slightest amount of moisture adhering to the uneven portion 7 on the side surface in the thickness direction of the edge of the steel strip in a limited amount of time. Particularly in recent years, as lines have become faster, it is necessary to take up a large amount of space for the drying process in order to perform sufficient drying, but the space in the process section will be reduced by that amount, so avoid this. This is often dealt with by increasing the speed of hot air. For this reason, it is becoming increasingly difficult to dry even the trace amount of moisture at the L-edge.

Under these circumstances, the inventor conducted a detailed study on residual moisture and found that a small amount of residual moisture at the edge of the steel strip has the following serious effect on the quality of the copper strip. In other words, 1 As shown in FIG. 4, the try-skin pass rolling mill 13
Cleaning steps 2, 3.
As shown in the figure (A-A arrow view in Figure 4), the water accumulates on the surface of the roll 14 during rolling, and this moisture is transferred to the edges of the steel strip lO, and the nozzles on the surface of the copper strip are transferred. or cause rust.

In surface treatment lines, residual moisture during the cleaning process immediately before coating changes the coating liquid content, causing a serious problem in product quality.

Conventionally, therefore, it was necessary to reduce the line processing speed and allow sufficient drying time, resulting in a significant drop in productivity.

Based on the above-mentioned findings, the present invention aims to prevent the quality of the copper strip from deteriorating and improve the productivity of the processing line by completely drying and removing trace amounts of moisture remaining in the copper strip [f section]. .

In order to reliably dry and remove the small amount of water as described in -1- in a limited space and time, various experiments have shown that it is impossible to do so with the conventional hot air blowing alone and that other methods are required. It turns out that a combination is necessary.

Therefore, the gist of the method of the present invention is that in the drying process after the cleaning process of the copper strip processing line, after the top and bottom surfaces of the copper strip are dried by hot air drying, the edges of the copper strip are locally heated and air-blown dried. The present invention provides a method for drying the edge of a copper strip, which is characterized by completely removing trace amounts of moisture adhering to the edge of the copper strip.

An example of an apparatus used to carry out the method of the present invention is shown in FIGS. 6 and 7.

In FIG. 6, 10 is a copper strip, 11 is a conventional drying device,
Reference numeral 12 denotes a complete drying device for the edge end for carrying out the method of the present invention, and 5a and 6a in the figure are a blow nozzle and a blow header. FIG. 7 is a view taken along the line B--B in FIG. 6.

In addition to the conventional drying device 11, the present invention provides a local heating device such as an induction heating coil 9 for drying trace amounts of moisture adhering to the uneven portion 7 (FIG. 3) in the thickness direction of the edge of the steel strip. It is installed at the edge of the steel strip lO and heats only the edge of the steel strip using an induced current, thereby heating and evaporating the stuck moisture. Here, in order to lower the atmospheric vapor pressure and evaporate in a short time, a nozzle 5a is provided that blows air only to the edge portion.

The capacity and length of the induction heating coil 9 used here can be arbitrarily designed depending on the amount of copper strip to be treated and the amount of residual moisture.

FIG. 7 shows that the induction heating coil 9 and the blower nozzle (not shown) are connected to a servo mechanism 15 which follows the meandering according to the amount of meandering in the widthwise direction of the edge of the steel strip. The present invention is configured as described below, so it is possible to completely remove the trace amount of water that has seeped into the cracks at the edge of the copper strip. This has the effect of improving yield and improving productivity.

[Brief explanation of the drawing]

Figure 1 is a system diagram of the cleaning process, Figure 2 is a side view of a conventional drying device, Figure 3 is a partial cross-sectional view of a copper strip showing moisture attached to the edge of the steel strip, and Figure 4 is a dry skin pass. rolling system diagram,
5 is a view taken along the line A--A in FIG. 4, FIG. 86 is a side view of the apparatus for implementing the present invention, and FIG. 7 is a view taken along the line B--B in FIG. 6. ■...Washing tank, 2...Washing tank, 3...Squeezing roll, 4...Drying device, 5, 5a...Blower nozzle, 6,
6a... Air blower, 7... Ear end section convex part, 8...
...Rolling roll, 9...Induction heating coil, 10...
・Steel strip, 11... Conventional drying device, 12... Device for implementing the present invention, 13... Dry skin pass rolling mill, 14... Roll roll, 15... Servo mechanism patent application Person Kawasaki Steel Co., Ltd. Agent Patent Attorney Yoshio Kosugi

Claims (1)

[Claims] 1 Steel: After the upper and lower surfaces of the copper strip are dried by hot air drying in the drying process after the cleaning process of the 'jF processing line, the steel A1? The edge of the copper strip is locally heated and dried by blowing air.
LI: edge=++ drying method for copper strips, which is characterized by completely removing trace amounts of moisture adhering to the edges.