For the reasons for the Classic Yarn fracture, there are two views:
One of the points is that the outer fiber, which is elongated during the spinning process, is first pulled off and then gradually spreads toward the inner layer of the fiber.
Ring spinning spun Classic Yarn, any small section of the outer fiber is the cylindrical spiral length, the inner fiber cylindrical spiral short, the central fiber was a straight line. So the outer fiber elongation, high tension; inner fiber elongation is small, low tension; the central fiber may not be elongated, or even crushed, the layers of fiber force is not uniform.
In the second point of view: when the Classic Yarn breaks, the center of the fiber is broken first, and then the fiber breaks to the outer layer.
When the elongated Classic Yarn is stretched and deformed, the elongation and deformation of the fibers in the Classic Yarns are different. The rule is that the center fiber has the largest elongation and elongation deformation (equal to the elongation deformation of the Classic Yarn), the elongation deformation of the outer fiber Minimal.
The cross-section of the Classic Yarn features: the broken corrugations of the staple fibers are irregular and appear to have a loose brush-like shape. This is due to the Classic Yarn in the fiber at different times, when a part of the tension of the larger fiber fracture, the fiber to the centripetal pressure decreases, a large number of fiber slippage and pull out.
Filament Classic Yarn or twist high staple fiber Classic Yarn, broken fracture more neat. This is due to the fiber is not easy to slip and pull out, part of the fiber after the break, the rapid expansion to the formation of the entire Classic Yarn.
The breaking process of the low twist filament Classic Yarn and the high twist filament Classic Yarn is quite different:
When the twist filament Classic Yarn breaks, the correlation between the individual filaments is small, and when they reach their own elongation at break, the difference of the elongation at break is not significant, and the breakage of the monofilament is almost simultaneously The
The breakage of each monofilament in the high twist filament Classic Yarn does not increase at the same time. The entire fracture process is completed in a longer elongation interval. The breaking strength decreases with increasing twist and breaks earlier than the low twist filament Classic Yarn, and after the start of the fracture, the tensile curve presents a longer extension.