1. Cobweb or off-edge
Due to improper winding tension, excessive axial traverse of the bobbin and spindle tube, poor operation, damage to the grooves at both ends of the bobbin, etc., the yarns at both ends of the bobbin, especially at the big end of the bobbin, slip intermittently or continuously. In severe cases, spider webs may form. Such defects will cause severe yarn breakage during unwinding.
2. Overlapping stems
Due to the failure of the anti-overlapping function, damage to the groove of the groove, or roughness and obstruction of the yarn channel, the yarns on the surface of the package overlap and stem, forming an overlapping package. Overlapping yarn strips are subject to excessive wear, are prone to end breakage, and are difficult to unwind.
3. Irregular shape
When the intersection of the grooves of the grooves is very rough, the yarn clearing board is clogged with flowers, and the tension device is not in the correct position, the yarn guide stroke becomes smaller, resulting in gourd bobbin; poor operation, incorrect bobbin position, resulting in Baotou bobbin; automatic stop of end breakage If the mechanism fails, a convex ring bobbin will be formed; the winding tension is too large, or the position of the spindle tube is incorrect, resulting in a bell-shaped bobbin; on the spindle-driven winding machine, the turning point of the forming cam is worn, or the position of the forming cam and the spindle is moved. , causing both ends of the tube to bulge or become embedded.
4. Loose bobbin and tight bobbin
Improper process settings of the tension device or improper pressure compensation of the bobbin bracket make the tension too high or too low. The former results in tight bobbins, while the latter results in loose bobbins; there are flying flowers or debris embedded in the tension plate, and the relative humidity in the workshop is too low, etc. The reason is that a loose bobbin with too low winding density is formed, the stability of the yarn loop is very poor, and delooping occurs when the yarn is unwound.
5. Big and small tubes
The operator’s incorrect judgment often results in large or small bobbins, which affects the production efficiency of subsequent processes and increases the bobbin yarn. This defect can be overcome by using a bobbin winding and length-fixing device.
Causes of internal defects in winding yarn
1. Poor joints
The splicer splices poorly; the splicing operation is not standardized when the winding ends are broken, causing the splice shape and yarn tail length to be substandard, such as long and short knots, loose knots, loop knots, etc. These defective joints will re-unravel in subsequent production processes, resulting in breakage.
2. Attachment of flying flowers and silk threads
The electronic yarn clearer fails; the yarn catcher is clogged, and the yarn waste is brought in by the suction nozzle; when there are flying flowers, yarn waste, or careless operation on the yarn channel, it will cause the flying flowers and silk waste to be rolled into the package together with the yarn.
3. Too many joints
The sensitivity of the electronic yarn clearer is set too high or the knot inspection is improperly adjusted.
4. Mixed raw materials and wrong batching
Due to poor production management, yarns of different linear densities, different batch numbers, and even different colors are mixed and wound on the same bobbin or batch. In the subsequent processing steps, this kind of defective tube is difficult to find, and finally “wrong warp” and “wrong weft” defects appear on the surface of the finished product.
5. Yarn wear
Failure of the auto-stop device for end breakage, failure to turn off the machine during end breakage, or burrs on the surface of the drum (drum) will cause excessive wear of the yarn, increase the hairiness of the yarn body, and reduce the strength of the single yarn.
The inherent defects of the bobbin include double yarn, oil stains, lapped ends, etc.
The high degree of automation of the automatic winding machine eliminates the dependence on human factors for high quality and high production of winding to a large extent. The product quality assurance system formed by perfect winding technology and strengthened winding production management enables the above-mentioned bobbin appearance defects and internal defects to be avoided.