JPS6279964A - Grinding chips removing apparatus in grinding steel strip ear part - Google Patents

Abstract

PURPOSE:To certainly remove grinding powder by installing a plurality of gas injection nozzles and a dust collecting hood onto a steel strip, in the apparatus for removing the grinding powder which are formed by the grinding for the ear part of the steel strip such as stainless steel heat rolled steel strip and accumulated. CONSTITUTION:A plurality of gas injection nozzles 2 and 3 and a dust collecting hood 4 are installed onto the upper surface of a steel strip 1. When the steel strip 1 whose ear part is grinding-treated by an edge grinder continuously moves to a grinding powder removing part, the grinding powder accumulated onto the upper surface of the steel plate are blown off towards the dust collecting hood 4 by the first gas injection nozzle 2. In this case, the grinder powder which is particularly heavy tends to collect into the form shown by the hatching. Then, the grinding powder is blown off by the second gas injection nozzle 3. The dispersion of the grinding powder in a wide range is prevented, and the powder is formed into a converged form. Therefore, the high dust collecting rate can be obtained with this apparatus without installing the special equipment.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention continuously removes grinding powder generated by grinding the edges of a steel strip such as a hot-rolled stainless steel strip and deposited on the steel strip. It relates to a removal device.

<Background technology> Generally, in cold rolling lines for stainless steel strips,
Increasingly, mill edges are removed by trimming the edges of hot rolled steel strips. This is because materials for which the trimming process is omitted tend to cause edge cracks during cold rolling, and there is a risk of inducing sheet breakage accidents due to edge cracks.Furthermore, flakes such as scale that occur at the edges may be removed during rolling. This is because the particles fly into the surface of the steel strip inside, causing inconveniences such as product flaws and roll flaws.

However, on the other hand, if the trimming step is added, the product yield will be poor due to the relatively large number of removed parts, leading to a rise in product costs.

In the past, attempts have been made to remove the inconvenient portion of the ear using a milling machine or using a plasma energy flow to remove the inconvenient portion of the ear as small as possible, but none of these methods yielded sufficient results.

Under these circumstances, a method of grinding the ears using a whetstone (coil edge grinder) has been developed (Japanese Patent Application Laid-open No. 113396/1983), and good results have been achieved.

However, when the edge of a hot-rolled stainless steel strip is ground using a coil edge grinder in this way, there is no effective means to prevent the generated grinding powder (grinding stone chips and stainless steel powder) from scattering over a wide area. In order to avoid grinding powder deposited on the top surface of the stainless steel hot-rolled steel strip from getting caught up in the tension reel and causing quality deterioration such as dents and scratches, great care must be taken to remove it.

By the way, in order to remove the grinding powder accumulated on the hot-rolled stainless steel strip by the edge grinder, a dust collector equipped with a flat nozzle as shown in Fig. 4 has been used. .

That is, an air nozzle (flat nozzle) 12 having a slit-shaped outlet above one end of the stainless steel hot-rolled steel strip 11 whose edges are ground with an edge grinder and which is continuously transferred toward the tension reel. The compressed air flow blown from the flat nozzle blows away the grinding powder accumulated on the upper surface of the hot rolled stainless steel strip, and the dust collection hood 13 arranged on the opposite side captures and discharges the grinding powder. It is.

Note that FIG. 5 is a schematic cross-sectional view schematically showing a state in which grinding powder is removed by this flat nozzle method.

However, with the conventional grinding dust removal method using a flat nozzle, (a) a certain amount of nozzle width is required, which poses a problem in terms of compact design, and when the nozzle width is wide, the compressed air flow is As the width of the flow becomes wider, as shown in Fig. 6, the feeding of the grinding powder to the dust collection hood 13 becomes difficult and a portion 14 is left behind. In addition, when the air volume and wind pressure are high, the dust (grinding powder) will be scattered widely, so the structure of the dust collection hood must be enlarged. (b) The dust collection rate is not very high (approximately 50 to 80%), especially if the steel strip has "waviness,""warp," or "bend."
If there is distortion such as , the rate will drop extremely.There are problems such as , and it was never satisfactory.

This was the same even when a nozzle having a plurality of small diameter holes as shown in FIG. 7(a) or (b) of the same type was used instead of the slit nozzle.

<Means for Solving the Problems> Based on the above-mentioned problems found in the conventional steel strip edge grinding dust removal means, the present invention has been developed to solve the This was done through research conducted by the present inventors in order to provide a compact device that can reliably remove the grinding powder accumulated on the top surface of the steel strip. equipment,
As shown in FIG. 1, the edges are ground with a grindstone and are opposed to the upper surface of the moving steel strip 1, and are inclined toward one side end of the steel strip 1 and in the width direction of the steel strip. a plurality of gas injection nozzles 2 and 3 arranged at intervals;
The present invention is characterized in that it includes a dust collection hood 4 disposed opposite to the end of the steel strip on the gas injection direction side.

It should be noted that the gas injection nozzle may be a normal cylindrical nozzle for injection of condensed nitrogen gas, and it goes without saying that an inert gas or the like may be used as the gas substance.

Now, in Fig. 1, when the steel strip 1 whose edges have been ground with an edge grinder is continuously transferred to the grinding powder removal section, the grinding powder accumulated on the upper surface of the steel strip is removed from the first gas gas. The jet nozzle 2 blows the compressed gas and grinding powder in the direction of the dust collecting hood 4 as shown in Fig. 2, but the flow of compressed gas and grinding powder at this time, together with the suction action of the dust collecting hood 4, prevents them from spreading. As shown in FIG. 3, especially the grinding powder with heavy electricity tends to gather in the shape shown by hatching in FIG.

Here, the grinding powder is further blown away by the second gas injection nozzle 3, and the dust collection hood 40
Combined with this action, the dust is sucked into the dust collection hood in a convergent manner without being scattered over a wide area.

Therefore, if you increase or decrease the number of nozzles as appropriate depending on the width of the steel strip (usually 2 to 3 are sufficient) and adjust the nozzle angle accordingly, you can collect the grinding powder that accumulates on the top surface of the steel strip. is carried out easily and reliably.

Moreover, since a nozzle with a narrow blowout width for compressed gas can be used, it is easy to increase the wind pressure, and it is possible to sufficiently cope with distortion of the plate.

<Example> Using the apparatus of the present invention as shown in FIG. We attempted to remove it under the following conditions.

Nozzle: Cylindrical compressed air nozzle with hole diameter 25raφ (compressed air feed port 6mIφ), Injection gas: Air, Nozzle inclination angle: 1st nozzle...10[degree], 2nd nozzle...45[degree], Nozzle Height: 50 mm, tip position of the first nozzle: 150 mm outside of the end of the steel strip opposite the dust collection hood.

Nozzle spacing near 50 liao, compressed air pressure = 4~6Kg/ca (normal factory letters), ° Injection air suction: 0.4m3/min, wind speed: 60m/S (near dust collection hood suction port), dust collection Hood width = 310 Liao, dust collection hood suction air! : 135m3/min, line speed: 60m/min.

When the dust collection rate at this time was measured, it was confirmed that dust collection was performed at a high rate of 90% or more, and it was also revealed that the dust collection rate could be further improved by slowing down the line speed.

<Overall Effects> As explained above, according to the present invention, there is no need for specially designed auxiliary equipment, and a sufficiently small amount of compressed gas is used (compared to about 7 to 1 in the past). We can provide a device for removing grinding powder from the edge of the steel strip, which is compact and has a structure that can achieve high dust collection rates, and improve the quality of cold-rolled steel strips without reducing line speed (E mark). This not only makes it possible to prevent scratches from filings, etc., but also dramatically reduces the amount of dust that is scattered, eliminating any negative impact on environmental measures or machinery, which is useful in industry.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a schematic perspective view showing an example of the device of the present invention, FIG. 3 is a schematic plan view of the main parts for explaining the grinding powder removal function of the device of the present invention, FIG. 4 is a schematic perspective view showing a conventional steel strip edge grinding powder removing device, and FIG. Fig. 6 is a schematic cross-sectional view of the main part to explain the grinding powder removal situation in the conventional device, Fig. 6 is a schematic plan view of the main part to explain the grinding powder removal situation in the conventional device, and Fig. 7 is the conventional device. 7(a) and 7(b) each show a different example. FIG. In the drawings, 1... Steel strip, 2... First gas injection nozzle, 3... Second gas injection nozzle, 4.13... Dust collection hood, 11... Stainless steel hot rolled Steel strip, 12...Air nozzle (flat nozzle), 14...
- Grinding powder left behind. Applicant Nippon Stainless Co., Ltd. Agent Tomi 1) Kazuo and 1 other person Chi 1 Group Gaku 2 Decoy 4th meal 6 illustration

Claims (1)

[Claims] A plurality of pieces are arranged at intervals in the width direction of the steel strip, facing the upper surface of the steel strip whose edges are ground by a grindstone, and tilted toward one side end of the steel strip. A method for removing grinding powder from an edge of a steel strip from an upper surface of the steel strip, comprising: a gas injection nozzle; and a dust collection hood disposed opposite to the end of the steel strip in the gas injection direction. equipment for.