Basic principle of sanding machine
When the fabric is sanded, the sand skin rotates at a high speed, and the sharp sand particles cut off the fibers on the surface of the fabric to make the surface of the fabric appear uniform and dense. surface. The sanded 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. The basic composition of the 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, a cloth drop frame, etc. The 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 flat and wrinkle-free. In addition, it is also equipped with a pair of edge suction devices, which has a widening effect on the fabric and is not easy to run off. Pad-rolling device The pad-rolling device of the sanding machine consists of a trough and a pair of re-rolling carts. The re-rolling carts can remove the moisture carried by the fabric to the utmost extent and help drying. Pre-drying part After the fabric is dipped, 60-70% of the moisture should be dried in the pre-drying process to reduce wrinkles on the cloth surface, which is conducive to the sanding effect of the cloth surface. Two sets of unit sanding machine sanding rollers have a total of 8 sanding sanding rollers and 2 6-row sanding rollers, which can wind different specifications of sanding rollers and rotate at high speed for sanding treatment. Commonly used sandpaper models are: 80-60P can be used for heavy fabrics, 100-120P medium-thick fabrics, 150-180p high-density light-weight fabrics. The sanding roller can run back and forth to achieve a satisfactory sanding effect. Pressure roller The sanding machine has 12 pressure rollers, which can control the upper and lower pressures and help 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 is composed of two DC motors, through the speed difference of the driving shafts of the two front and rear DC motors, the tension of the fabric is adjusted to adjust the sanding effect. Fabric drop frame The fabric is continuously dropped into the fabric stacker through the fabric drop frame, and then sent to the next process by the car for washing and dyeing. The main factors affecting the sanding effect The quality requirements of semi-finished products The quality of semi-finished products is the main factor affecting the sanding effect, which has a greater impact on the sanding effect and dyeing performance. Semi-finished products should be made on request: smooth cloth surface, no wrinkles, no scratches, clean desizing, thorough cooking, good hair effect, soft hand feeling, etc. Tension In the process of sanding, 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 decrease more, which will affect the wearability, make the sanding effect worse, and cause the cloth surface to be blurred and the fluff is uneven, resulting in defects such as rubbing willows. Comparing the strength of mercerizing and sanding, the abrasion rate can be obtained. Generally, the strong abrasion rate of the sanding cloth is controlled within 30%. Vehicle speed The speed of the vehicle will also directly affect the effect and strength of the sanding. The longer the time the fabric is in contact with the sanding roller, the better the sanding effect and the more uniform the fluff. But the speed should not be too slow and the tension should not be too high. If the vehicle speed is too slow and the tension is high, the strength will be greatly reduced, and even sanded holes, broken edges, etc. will appear. If the speed is too fast, the sanding effect will not meet the requirements. Our factory controls the speed of 20-28m/min according to the characteristics of different fabrics. Therefore, it is necessary to select appropriate sandpaper in the production and carefully control the speed of the craft. Pressure The pressure of the pressure roller will affect the size of the wrapping angle of the fabric on the grinding roller and the size of the contact surface between the fabric and the surface of the emery roller. The greater the pressure, the larger the contact area, and the smoothing effect will naturally be better; but the pressure should not be too high, otherwise the fabric will be easily worn. Generally, the pressure of the new sand skin should be lower, and the pressure of the old sand skin should be increased appropriately, or the new sand paper should be replaced. According to the sanding effect of the machine, the sand paper specifications and different specifications of sand skin have obvious influence on the suede effect. The higher the number of skins, the shorter and uniform fluff will be ground, and the smaller the strength drop will be. On the contrary, the longer the fluff will be uneven and the greater the strength drop will be. Therefore, the selection of the mesh size of the sand skin should be determined according to the thickness, thickness and strength of the fabric.
