Determination of Denier and Strength of Single Filaments by Vibroscope and Heim Tensile Tester

The punched-card method is illustrated, with a description of the procedures used in analyzing the data on single cotton fibers. The samples were tested for 7 properties, from which 5 more were derived by computation. For each of these 12 properties there were prepared a histogram showing the distribution of the property values within variety groups, means and standard deviations for 6 subgroups within each variety, and a three-factor analysis of variance of the means for all varieties and subgroups. The steps in obtaining these results from the punched cards are outlined. Some advantages of this method over the desk-calculator approach are discussed.T HE PURPOSE of this paper is to draw attention to the use of punched-card methods in the evaluation of the physical properties of single textile fibers and to present some results which have been obtained at the laboratories of the Textile Research Institute in applying this procedure to the study of cotton and wool fibers.During the course of the past 12 months, increasing attention has been given to the research on singletextile-fiber properties. The single-fiber work on cotton aims at a better understanding of cotton through a concerted program to evaluate differences in cotton types, the effects imposed upon the physical properties by maturity, and the influence of morphology and treatments on the measured physical properties. Another branch of the cotton program includes research on the progression of physical changes exhibited by cotton during the course of its processing from the bale to the finished cloth. This is a companion project to that in which changes in the degree of polymerization are being followed in cotton from the bale to the cloth by fluidity studies of the cotton cellulose in cupriethylene diamine solutions [18].

Section: Application Of the Punched-card Methods Tomentioning

confidence: 99%

The Application of Punched-Card Techniques to Data on the Physical Properties of Single Fibers

Wakeham

Wakelin

1950

“…Fineness measurements were made on these wools by means of a vibroscope modeled after that of Gonsalves [6]. The vibroscopic measurements were made by means of a 0.1-g. weight, with the points of contact 3 cm.…”

Section: Mechanical Propertiesmentioning

confidence: 99%

Comparison of Wools Between and Within Several Breeds of Sheep

O'Connell

Lundgren

1954

Wools produced from five widely differing breeds of sheep which were raised under the same environmental and dietary conditions have been studied. By means of stress-strain analysis of wet fibers, certain mechanical properties have been evaluated and differences shown to exist among the several breeds, independently of differences in fineness among the wools. Wools from individual animals within breeds were also found to differ significantly in mechanical properties. The dependency of mechanical properties on the fineness of wool has been found to vary in a manner which indicates that crimp in the fiber strongly influences mechanical properties. Crimpy wools tend to have a negative dependency of mechanical properties on diameter, whereas the low-crimped wools tend to have a positive dependency of mechanical properties on diameter. Correlations have been established between the various properties studied, and high interdependencies have been found.

“…Examples of Results Figure 7 shows a typical stress-strain curve for a Rambouillet wool fiber tested in water at a constant rate of loading of 2 g./grex/min., based on the original diameter of 5.8 grex as measured vibroscopically [4]. It was loaded, therefore, at a rate of 11.6 g./ min., and, since the chart moved at a rate of 10 in./ min., each inch of chart travel corresponds to 0.2 g./ grex, or 1.16 g. of force.…”

Section: Principles and Designmentioning

confidence: 99%

Single Fiber Stress-Strain Apparatus

Preusser

O'Connell

Yeiser

et al. 1954

THIS PAPER describes a desk-type, autographically recording instrument built especially for precise stress-strain measurements of single fibers, which are tested in a horizontal plane to facilitate measurements in solvent media.' The instrument was designed primarily for constant-rate-of-load (stress) testing, but provision for constant-rate-of-elongation testing over a limited range of rates is also incorporated. The mechanical and optical principles used are similar to those used in earlier instruments described by Osumi and Kato [7] and Montcrieff [5].The present report will facilitate comparison with various other laboratory-constructed and commercial instruments [1,2,3,8 ] , and describes in detail an apparatus that has been used over a period of several years, with uniformly satisfactory performance, in research on the influence of chemical environment on wool fibers [6]. Principles and DesignThe principal mechanical components are shown schematically in Figure 1, and the basic electrical circuit is illustrated in Figure 2. Load is applied to the fiber through a twisting torsion wire, and elongation by a moving rack. The load and elongation units are powered separately by two-phase, induction-start, synchronous motors of the type commonly used for constant-speed chart drive in recording instruments. The loading and elongation motions are coordinated by means of a twin photocell activated by a beam of light reflected from a mirror mounted on the torsion wire. The recording chart is mounted on a drum driven by the loading motor; the pen is moved by the elongation motor. By means of a gear shift, the pen displacement may be selected to travel 1, 5, or 10 times the distance over which the fiber elongates. FIG. 1. Schematic diagrazn of mechanical components.