Analysis Of Several Factors Affecting The Strength And Elongation Of Short Staple Yarn

< p > < < a > href= > http://www.91se91.com/news/ > > yarn > /a > strength and elongation are mainly composed of two aspects: fiber property and yarn structure. The strength and elongation of blended yarns are closely related to the properties of blended fibers and blending ratio. The external factors such as temperature, humidity and strength test conditions are basically the same as those of fibers.

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< p > 1, fiber property < /p >

< p > fiber length and linear density: < /p >

< p > when the fiber length is longer and the fiber is thinner, the frictional resistance between fibers in the yarn is larger, and it is not easy to slip, so the yarn strength is higher.

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< p > when the fiber length uniformity is good, the fiber is thin and uniform, the evenness of the yarn is uniform, the weak ring is few and not significant, which is conducive to the improvement of yarn strength.

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< p > fiber strength: < /p >

< p > when the strength and elongation of the fibers are large, the strength and elongation of the yarns are larger, and the strength of the yarns is higher when the fiber strength and elongation irregularity are small.

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< p > surface friction properties of fibers: < /p >

< p > when the friction coefficient of fiber surface increases, the slip resistance between fibers increases, the slip length Lc decreases, the percentage of slipped fibers decreases, and the yarn strength increases.

Increasing the crimp number of fibers can increase the sliding resistance between fibers.

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< p > 2, yarn structure < /p >

< p > (1) the influence of short fiber yarn structure on its strength and elongation is mainly reflected in the twist.

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< p > when the twist coefficient increases, the frictional resistance between wood fibers increases and is not easy to slip. This is a strong positive side for the strength of short fiber yarns. However, when the twist coefficient increases, the fiber strength decreases with the increase of fiber inclination, and the strength of yarn in the axial direction decreases, and the fiber breakage in the yarn increases. At the same time, the yarn diameter increases when the fiber is tilted, which is unfavorable to the relative strength of yarns.

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< p > (2) the effect of joint stock < /p >

< p > single yarn synergy makes the strands (plyyarn) evenness, and the contact between single yarns increases the cohesion between the outer fibers of the single yarn, and the strength of the ply yarn is greater than that of the single yarn.

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< p > (3) the arrangement of fibers in < a href= "http://www.91se91.com/news/index_c.asp" > short fiber yarn < /a > /p >

< p > the strength of rotor spun yarn is lower than that of ring yarn: in the rotor spun yarn, there are more irregular fibers arranged in fold, curl, circle and so on, and the normal pfer fibers are less, resulting in poor contact between fibers and fibers, and more slipping fibers during stretching.

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< p > (4) bulked yarn < /p >

< p > the tensile fracture strength of expanded yarn is smaller than that of traditional yarn, while the elongation at break is larger.

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< p > structural characteristics: using two kinds of fibers with different heat shrinkability to heat shrinkable fibers after blending, so that the high shrinkage fibers in the yarn can be fully retracted, and at the same time, the normal shrinkage fibers with small heat shrinkage can be compressed and wrinkled.

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< p > tensile fracture process: the tensile strength of bulky yarn is smaller than that of the external force, and the tension of the fibers is uneven.

When stretched, only a small part of the fiber takes on external force, while other fibers wrinkle and relax.

When a fiber is broken, the latter fiber is stretched and stretched until it breaks.

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< p > (5) < a href= "http://www.91se91.com" > textured yarn < /a > elastic yarn < /p >

< p > depending on various setting methods, each fiber has a helix spring or curl like directional wrinkle curve.

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< p > during the considerable period of stretching, the fibers are gradually stretched out under the condition of little increase in tensile force, and they all have very high elongation at break.

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