Management involves four basic activities—planning and decision making, organizing, leading, and controlling. Although there is a basic logic for describing these activities in this sequence (as indicated by the solid arrows), most managers engage in more than one activity at a time and often move back and forth between the activities in unpredictable ways (as shown by the dotted arrows).
x % Span length is the distance spanned by x %of fibers in the specimen being tested when the fibers are parallelized and randomly distributed and where the initial starting point of the scanning in the test is considered 100%. This length is measured using "Digital Fibrograph‘.
The original idea of the photoelectric scanning or Fibrograph method has been developed by Hertel in 1940 for testing cotton lint. This test method is much faster than the array method and is used widely in ﬁber laboratories for measuring fiber length and length distribution.
The most frequent length in a fibrous sample is called staple length. Staple length is one of the most important factors of cotton quality because both ﬁber ﬁneness and fiber tensile strength are associated with staple length. The longer staples are usually finer and stronger than the shorter staples.
The ﬁber sorter is an instrument which enables the sample to be fractionalized into length groups. The Baer sorter, the Shirley comb sorter, and the Suter-Webb sorter are the most popular method of the fiber sorter. Basically, the operation involves four main steps:
Preparation of a fringe or tuft with all ﬁbers aligned at one end.
The separation or withdrawal of ﬁbers in order of decreasing length.
The preparation of a sorter diagram by laying the fibers on a black velvet pad in decreasing order of length, the ﬁbers parallel and their lower ends aligned along a horizontal base line as shown in Figure.
The analysis of the sorter diagram.
After fineness, length is the most important property of a fiber. The length of cotton is directly related to its spinning performance. Knowledge of fiber length is necessary to manufacture a yarn of specific size on ring spinning system and typically longer fibers are used to manufacture fine yarns. Longer fibers are generally more uniform, finer, and stronger than shorter ones.
Graphical Representation of Mass Variations Graphical representations are aimed at providing easy analysis possibilities as well as providing more complete information than the numerical estimates. The following graphical representations are common with the latest generation evenness testers. Spectrogram 3D Spectrogram Variance Length Curve 3D Variance Length Curve Normal Diagram Cut Length Diagram Histogram Spectrogram The […]
Yarn Evenness & It’s Classification Evenness, Unevenness, regularity, and irregularity are common terms used to describe the degree of uniformity of a textile product. In the textile ﬁeld, the uniformity of products like the lap, sliver, roving or yam is expressed in terms of evenness or regularity or in terms of unevenness or irregularity. A […]
Unevenness and Coefficient of Variation of Yarn: The average value for all the deviations from the mean which is expressed as a percentage of the overall mean is called percentage of Mean Deviation (PMD). The coefficient of mass variation CV % is the ratio of standard deviation of mass variation divided by average mass variation.