The basic principle of sanding machine_Latest developments

Basic principle of sanding machine





When the fabric is sanded, the sand skin rotates at a high speed, and the sharp sand grains cut off the fibers on the surface of the fabric, so that the surface of the fabric presents a uniform and dense suede. The brushed fabric has a bulky appearance and a soft and thick feel. Sanding products have developed rapidly, and sanding has become one of the important fabric finishing processes.





Basic composition of sanding machine



The sanding machine is composed of a cloth feeding part, a padding device, a pre-drying part, two sets of unit sanding machines, and a cloth falling frame.



Cloth feeding part

The cloth feeding frame of the sanding machine is equipped with a tension regulator, which can adjust the tension according to the thickness and weight of the fabric to ensure that the fabric is smooth and wrinkle-free. In addition, it is also equipped with a pair of edge suction devices, which have a widening effect on the fabric and are not easy to deviate.



Padding device

The padding device of the sanding machine is composed of a tank and a pair of heavy padding cars. The heavy padding cars can remove the moisture carried by the fabric to the maximum extent, which is helpful for drying.



pre-baking part

After fabric padding, 60-70% of the moisture should be dried in the pre-drying process to reduce the wrinkles on the cloth surface and facilitate the sanding effect of the cloth surface. Two sets of unit sanding machine



sanding roller

There are 8 sanding sticks and 2 6-edge grinding sticks, which can be wound with different specifications of sanding sticks and rotate at high speed for sanding treatment. Commonly used sandpaper models are: 80-60P can be used for heavy fabrics, 100-120P for medium-thick fabrics, and 150-180P for high-density light and thin fabrics. The sanding roller can run back and forth to achieve a satisfactory sanding effect.



pressure roller

The sanding machine has 12 pressure sticks, which can control the pressure up and down, which helps to adjust the sanding effect, but the adjustment scale should not be too low, otherwise it will seriously affect the strength.



There is also a chain shaft adjuster modified by our factory on the sanding machine. It consists of two DC motors, through the speed difference of the drive shafts of the two front and rear DC motors, the tension of the fabric is adjusted, thereby adjusting the sanding effect.



Cloth rack

The fabric is continuously dropped into the stacking car through the drop rack, and sent to the next process by car for washing and dyeing.































The main factors affecting the effect of sanding



Quality requirements for semi-finished products

The quality of semi-finished products is the main factor affecting the effect of sanding, and it has a great influence on the effect of sanding and dyeing performance. Semi-finished products should meet the requirements: smooth cloth surface, no wrinkles, no scratches, clean desizing, scouring, good hair effect, soft hand feeling, etc.



tension

During the sanding process, the greater the tension of the cloth surface, the closer the contact between the cloth surface and the sanding roller, and the better the sanding effect. However, the tension should not be too high, otherwise the strength of the fabric will drop more, which will affect the wearing performance, make the sanding effect poor, and cause the cloth surface to be flowered and the fluff uneven, resulting in defective products such as milled willow. Comparing the strength of mercerizing and sanding, the wear rate can be obtained. Generally, the strong wear rate of sanded cloth is controlled within 30%.



speed

The speed of the vehicle will also directly affect the sanding effect and strength. The longer the fabric is in contact with the sanding roller, the better the sanding effect and the more even the pile will be. But the speed should not be too slow, and the tension should not be too large. If the vehicle speed is too slow and the tension is high, the strength will be greatly reduced, and even sanding holes and broken edges will appear. If the speed is too fast, the sanding effect will not meet the requirements. According to the characteristics of different fabrics, our factory controls the speed of the machine at 20-28m/min. Therefore, appropriate sandpaper should be selected during production, and the speed of the process should be carefully controlled.



pressure

The pressure of the pressure roller will affect the size of the wrapping angle of the fabric on the grinding roller, as well as the size of the contact surface between the fabric and the surface of the sanding roller. The greater the pressure, the larger the contact area, and the better the sanding effect; but the pressure should not be too high, otherwise the fabric will be easily worn. Generally, the pressure of the new sanding surface should be lower, and the pressure of the old sanding surface should be increased appropriately, or new sandpaper should be replaced, depending on the grinding effect of the machine.



Sandpaper specification

The impact of different specifications of sand skins on the effect of suede is obvious. The higher the mesh number of sand skins, the shorter and uniform the fluff will be, and the smaller the strength drop will be. Also bigger. Therefore, the selection of the mesh number of sand leather should be determined according to the thickness, thickness and strength of the fabric.