Richard Frydrych

A New Method of Measurement of the Inter-fiber Force

The friction and cohesion forces are some of the most important parameters that affect the yarn spinnability and tenacity. A new and simple device was carried out in order to quantify the friction and cohesion forces during a quasi-static fiber slippage in a sliver. This device was composed of two identical small carriages. One of them was fixed, whereas the second was moving on a linear guide. A piece of sliver was put down in the carriage channel in zero-gage position. The sliver was compressed with the upper carriage sides, where two identical weights were loaded. This apparatus was tested under different loads, sliver counts and speeds. The results were analyzed in order to check out the parameters which characterized the friction force during inter-fiber slippage.

Silk Waste/Cotton Blended Yarns in Cotton Microspinning: Physical Properties and Fibre Arrangement of Blended Yarn

The microspinning technology has generally been used for cotton in the case of small scale spinning test methods (50 gram fibres). One type of silk fibre waste -pierced cocoonprepared previously as short silk fibre with cut length of 35 mm is blended with cotton fibre to obtain further data concerning two blending techniques in this microspinning, and to compare pure and blended yarns. The intimate (before carding and drawframe blending as well as the roll settings in the drawing system are being examined. The silk content was changed at 0/100, 25/75 and 50/50 ratio for a yarn count of 30 tex. The physical properties, the irregularity and the fibre arrangement as terms of the Index of Blending Irregularity and the Migration Indices of the blended yarns have been studied. In addition, the effects of the blending techniques as well as those of the silk content have been brought to the fore.

Effect of seed coat fragments on cotton yarn structure: impact of fragment size, attached fibres and position within yarn core

Seed coat fragments are a major source of cotton yarn imperfections. This article discusses the factors influencing the disruption caused by seed coat fragments in ring-spun yarn structure with a focus on three characteristics: the fragments size, the amount of fibres attached to it and its position relative to the yarn core. The three characteristics were investigated through two experiments involving various types of yarn defects and a range of ring-spun yarn counts. Results presented in this article indicate that the three factors considered have a significant influence on the intensity of the disruption the seed coat fragment causes in the yarn structure, and are determinant of the type of defect that this disruption engenders (short/long defect).

Qualitative classification of cotton stickiness in the H2SD high speed stickiness detector

Regularly confronted with the problem of cotton stickiness during spinning, those in the international market wish to see the implementation of a cotton bale classification system to describe the degree to which a given cotton is contaminated. Thermodetection equip ment such as the H2SD high speed stickiness detector may be suitable for such a task. With a working capacity equivalent to that of HVI lines, this instrument evaluates the stickiness of cottons contaminated by insect honeydew. This paper discusses the feasibility of a qualitative classification based on within-bale distribution of the number of sticky points. A detailed example obtained with the H2SD illustrates the qualitative classification proce dure. Sticky bales can be separated from uncontaminated bales for the latter to be marketed with a guaranteed stickiness level below a set threshold and a litigation risk selected in advance.

Inter Fiber Frictional Model

One of the effective forces in the textile process is friction. A new and simple device is developed in order to quantify the friction forces during a quasi-static fibre slippage in sliver. The device is composed of two identical clamps, one of which is fixed and the other moving through a linear guide. A piece of sliver was maintained under controlled pressure in the zero gage position of the two clamps. The frictional force during the fibre slippage in the sliver was measured using three different speeds, eight different normal loads and three different sliver counts. Five replications were preceded for each factorial combination. In general, the frictional force increased with the speed, but the analysis of variance of the data indicated that the effect was not significant, whereas the effect of the normal load on frictional force was positive and highly significant. A statistic model based on these results is proposed with respect to sliver count and normal load. Following this model, the effects of the normal load and sliver count on the frictional force were not linear.