JPH027016Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Purpose of the invention] (Industrial application field) This invention provides excellent grinding performance in grinding operations such as removing surface defects from strip coils of steel plates, stainless steel plates, titanium plates, etc. manufactured through hot and cold rolling processes. The present invention relates to a grinding belt made of abrasive cloth coated with abrasive grains on a lower layer coated with a coating of walnut shell particles capable of exhibiting continuous grinding. (Prior art) Cork belts, which have traditionally been used for polishing the edges of plate glass, have recently been used to add a high-quality image to the finished surfaces of metal products, and for polishing difficult-to-cut metals. The cork belt has been reviewed and plans have been made to develop and expand demand for products that can meet this requirement, but the feature of cork belts is that they are mainly used for light grinding loads (0.1 to 1.0 HP per 25 mm processing width), rather than for grinding. It has a wide range of uses as a scrub. Therefore, with conventional products that use cork as a core, if the grinding load is high (more than 2 H.P. per 25 millimeters of processing width) due to the grain strength and cushioning properties of the cork, the cork grains will break and the belt will wear out prematurely. As this is unavoidable, the grinding life of the belt is shortened. On the other hand, when grinding a metal strip coil, it is impossible to avoid applying a locally high grinding load to the belt for the following reason. That is, warping in the width direction of the coil, burrs due to cutting (trimming) at both ends of the coil, and uneven thickness in the width direction of the coil due to roll bending of the rolling mill.
Therefore, conventional cork belts have not been able to exhibit sufficient grinding performance and grinding durability for the grinding work of removing surface defects from metal strip coils. (Problems to be solved by the invention) In view of the above, this invention uses a base layer that has moderate hardness, crushing strength, and elasticity, instead of using a brittle elastic nodule like cork that is extremely soft and has good cushioning properties. The object of the present invention is to obtain a grinding belt that is formed by coating particles of walnut shells having abrasive properties as a coating material and exhibits excellent grinding performance and grinding durability. [Structure of the invention] (Means for solving the problems) In order to achieve the above object, this invention uses an adhesive on the surface of a flexible base material (cloth, paper, vulcanized fiber, or a combination thereof). (Epoxy resin, phenolic resin, urethane resin alone or in combination) with an average particle size of approximately 0.2~
A lower layer is formed by coating walnut shell particles that have been crushed and classified into 5.0 mm particles, and then abrasive grains with an average particle size of approximately 0.07 to 0.50 mm (equivalent to JIS particle size standards No. 150 to 36) are applied on top of the coating. This is an endless belt made of an abrasive cloth with a surface layer coated with an adhesive. (Function) To explain the function and effect of this invention, the abrasive belt of this invention is used because the walnut shell that forms the lower layer coated on the surface of the base fabric has appropriate hardness, elasticity, and abrasiveness. During the grinding process, the walnut shell grains are moderately abraded, and the abrasive grains gradually develop into sharp edges, exhibiting grinding properties.The walnut shell grains are abraded to an appropriate level, and the abrasive grains gradually develop into sharp edges, demonstrating excellent grinding properties. It has much better durability than when using a normal abrasive cloth. (Example) An example of this invention will be described below based on the drawings. FIG. 1 is an enlarged explanatory view of the cross section of the abrasive cloth 2 constituting the abrasive belt 1 of this invention. The surface of a flexible base material 3 (cloth, paper, vulcanized fiber, or combination backing material thereof) is coated with walnut shell particles 4 (pulverized and classified to an average particle size of 0.2 to 5.0 mm) as a coating material. In order to form a lower layer, an adhesive 5 for fixing walnut shell particles is applied and fixed, and the surface of the walnut shell particles 4 has an average particle diameter of about
Abrasive grains 6 (alumina, alumina-zirconia,
The adhesive 7 for polishing abrasive grains is coated with silicon carbide (silicon carbide) and then coated as a coating to form a surface layer and fixed. As the adhesives 5 and 7, epoxy resin, phenol resin, and urethane resin may be used alone or in combination. Next, the grinding belt 1 formed by processing the above-mentioned abrasive cloth 2 into an endless belt is attached to the grinding head of a strip grinding machine for grinding metal strip coils, as shown in FIG. Furthermore, the size of the grinding belt 1 is 1500
There are also large ones measuring 3,200 mm in width and 3,200 mm in circumference. In the figure, a wide contact roll R _C made of an elastic material such as rubber, which also serves as a drive, or a narrow contact foil is crimped onto a strip C on a roll running at a relatively low speed in the direction of the arrow, and a grinding head is attached. An endless grinding belt 1 with an abrasive material fixed almost uniformly on the outer circumferential surface is stretched between the idler roll R _D provided above and the contact roll R _C or contact foil. While rotating and moving, the strip coil can exhibit excellent grinding performance because it removes surface defects (chemical defects such as oxide films and damaged layers, and physical defects due to scratches). The peripheral speed of the grinding belt 1 is 600 m/min for titanium material and 1300 m/min for stainless steel material.
The feeding speed of the strip coil is suitable for grinding conditions of 5 m/min to 15 m/min, and water or oil is generally used as a lubricant for grinding stainless steel materials and water for titanium materials. However, the grinding durability of the grinding belt does not deteriorate. Next, we will show a comparative example of a grinding belt using walnut shell particles of this invention and a grinding belt using commercially available cork particles, and explain that there is a significant difference in performance. 1st Example Commercially available cork grains and walnut shell grains were each prepared using JIS
-R-6001 "Particle size distribution of abrasive", the particles were sieved to particle size #16 (average particle size of about 1.2 millimeters). The sized particles are applied to the surface of a cotton twill cloth used for ordinary abrasive paper as a base material through a certain amount of adhesive mixed with an epoxy resin (bisphenol diglycidyl ether) and a liquid polyamide curing agent. After each layer has been adhered in a single layer and most densely, the adhesive is dried, and a certain amount of epoxy-polyamide adhesive is applied to the surface of the dried base material particles, and then applied on top of JIS particle size #80 (average particle size). Approximately 750 g/m ² of fused alumina abrasive (approximately 0.2 millimeters) is applied, and the adhesive is heated and dried, then cured. An endless belt with a width of 100 mm and a circumference of 2100 mm is made from this sample. Table 1 shows the results of grinding using a surface grinder (manufactured by Tahara Shoei Kiko) under the following conditions. Grinding conditions: Work material SUS 304 25mm width x Xm length Belt speed 1400m/min Workpiece feed 10m/min Grinding load 2.5HP/25mm width Workpiece material Grinding fluid Water Grinding direction Down cut

[Table] Second Example After drying the adhesive epoxy resin to which the abrasive of the first example was attached, apply approximately 170 g of liquid phenol formaldehyde resin (BRL-2683 manufactured by Showa Kobunshi Co., Ltd.) on top of the abrasive layer. Table 2 shows the results of trying the same grinding as in the first example after coating m ² and drying and curing it.

[Table] [Effects of the invention] This invention has the above-mentioned structure, so it eliminates the drawbacks of conventional cork belts, etc., and improves the speed and cushioning properties of walnut shell grains in grinding operations such as removing surface defects from metal strip coils. The strength is suitable for this work, and the effect of exhibiting excellent grinding performance and grinding sustainability is extremely large. Incidentally, scanning electron micrographs (magnification: x300) of the cross sections of the cork particles and walnut shell particles used above are shown in FIGS. 3 and 4, respectively. It can be seen that walnut shell grains have a much more dense structure than cork grains. More specifically, experiments have shown that the compressive stress of walnut shell particles is about 6 times that of conventional cork shell particles, so even under high loads during grinding, abrasive grains can easily break down. Since it does not fall off, it provides the benefit of sustained grinding performance.

[Brief explanation of the drawing]

Figure 1 is an enlarged cross-sectional explanatory diagram (side view) of the abrasive cloth that constitutes the abrasive belt of this invention, Figure 2 is an explanatory diagram (front view) of the strip grinding machine with the abrasive belt attached, and Figure 3 is A scanning electron micrograph of a cross section of a cork particle, and FIG. 4 is a scanning electron micrograph of a cross section of a walnut shell particle. Explanation of symbols of main parts, 1... Grinding belt, 2
... Abrasive cloth paper, 3 ... Base material, 4 ... Walnut shell particles,
5... Adhesive (for the same as above), 6... Abrasive grains.

Claims (1)

[Claims for Utility Model Registration] (1) The surface of a flexible base material 3 is coated with walnut shell particles 4 as a coating via an adhesive 5 to form a lower layer, and then abrasive grains 6 are coated on top. A grinding belt characterized in that an abrasive coated paper 2 provided with a surface layer is formed into an endless belt. (2) The grinding belt according to claim (1) of the utility model registration, characterized in that it is coated with walnut shell particles 4 that have been crushed and classified to an average particle size of 0.2 to 5.0 mm as a coating material.