Do Not Understand Cloth, Why To Make Emery Cloth (cloth Characteristics)

Cloth is the most important substrate of sand belt, which has good softness and high strength. Cotton cloth and polyester cloth are the main substrates used for making abrasive belts and coating abrasive tools. In recent years, polyester-cotton blended cloth has been used more and more in the manufacture of coated abrasion-coated tools. According to different use objects can be made of different fibers, different strength, different organization and density of cloth base. The types of fibers can be cotton, hemp, synthetic fibers, artificial fibers and polyester fibers, etc., so the cloth made is divided into cotton, linen, synthetic fiber cloth, artificial fiber cloth and polyester fiber cloth. However, cotton is the most used, it shows that smooth, good winding, good bonding with various binders, and cotton materials are rich and cheap. The artificial fiber substrate is not suitable for animal adhesives. For high strength requirements of the sand belt, can use linen, nylon cloth and polyester cloth as the base material.

Cloth base and paper base also have different weight classes. In general, heavy cloth is mainly suitable for coarse grain and strong grinding, light cloth is suitable for fine grain and polishing grinding. The classification standard of cloth substrate weight is different in all countries and major manufacturers in the world, and each has its own provisions, as shown in Table 1 and Table 2. The domestic selection basically follows the above principles.

Synthetic fiber cloth and polyester fiber cloth were developed after people realized some defects of cotton cloth (such as poor water resistance and relatively low strength). In the 1960s, the first successful trial production of nylon based sand belt in the United States, named Microlon sand belt, is about 20 times more efficient than the general cloth based sand belt grinding. In the 1970s, polyester fiber substrate was produced, which has better tensile strength and lower elongation, flat surface, better heat resistance and water resistance, and is suitable for manufacturing high-efficiency sand belts with heavy loads. Norton sand belt produced by the United States Norton Company is the use of this substrate, it has attracted wide attention in the world, and has obtained rapid development. In some industrial developed countries, polyester products have accounted for 7% to 8% of the entire cloth coated abrasive, while the United States in 1981 has reached 13.5%, and is still rising, most of which are used to make sand belt.

The physical and mechanical properties of 3M cotton and polyester fiber substrates are listed in Table 3.

The requirements of the sand belt for the original cloth are

1 Fiber type.

In general, the vast majority of the original cloth used in the coated abrasive is cotton, which is determined by its superior performance. It is mainly manifested in:

① Good bonding performance with various binders;

② The surface is flat and the deflection is good

③ High strength, small elongation;

④ Sufficient sources, cheap prices.

Artificial fiber and synthetic fiber products have flat surface and high strength, but the elongation is generally large, selective to the binder, and the treatment is more difficult. Due to the improvement of raw cloth processing technology, the application of artificial fiber and synthetic fiber products has also been rapidly developed, especially polyester cloth. Because of its flat surface, high breaking strength and good waterproof performance, after high temperature tensile shaping treatment, elongation is small, no deformation when used, etc., it has been widely used.

Since the end of the 1990s, due to the introduction of manufacturing technology from Japan and South Korea, polyester-cotton blended fabric has been rapidly developed in China because of its advantages of thick fabric, flat surface, high strength and cheap price, but because the polyester-cotton blended fabric is composed of cotton fiber and polyester fiber, and the two have different requirements for the original fabric treatment. To adopt the same treatment method to treat both cotton and polyester fibers, it needs to be taken seriously.

2 Mix cotton.

Cotton quality plays a decisive role in the quality of the original cloth, sand belt cloth should be used high-quality cotton, cotton fiber fine and long, suitable maturity, woven cloth quality, dense, white, less impurities, strength, elongation is small, so the original cloth with high requirements for cotton.

For blended fabrics, the blending also includes the proportion of various fibers.

3 Weight.

As with the requirements for paper, different coated abrasives have different requirements for the weight of the original cloth. In general, heavy cloth is mainly suitable for coarse grain size and strong grinding; The lightweight cloth is suitable for fine grain size and grinding and polishing. Page emery cloth has lower requirements for the original cloth, and light cloth can be used. The sand belt generally adopts heavy cloth with high fracture strength. Countries, major manufacturers according to the weight of the original cloth unit area, the original cloth is divided into several levels for selection,

4.Original fabric structure and yarn count.

Coated abrasives generally use twill, which is due to its thick texture, soft, high strength.

The fine twill cloth with large count, fine yarn and smooth surface is suitable for producing fine grain emery cloth; The coarse twill with small count, thick yarn, high strength, thick and soft is suitable for the production of coarse-grained coated abrasive tools.

The twill coated with abrasives is generally made of yarn fabric or half-thread fabric of radial weft. In the production of fine grain, plain cloth can also be used, because it is smooth and suitable for polishing.

5 Warp and weft density, strength and elongation.

The density of the original cloth used for coating abrasive tools should be moderate to maintain softness and strength. Too dense, brittle, and affect the adsorption of adhesive; Too thin, low strength, too much glue.

High warp density and low weft density are the second requirements for the original cloth density of coated abrasives. This is because the abrasive coating requires the original fabric radial strength is large, the zonal strength is small, easy to tear and decided.

Small elongation is also a requirement for cotton coated abrasives.