Abstract
The Nepotometer is in many respects a miniature card designed to simulate on laboratory samples of cotton the effects of actions encountered during the carding opera tion which are largely responsible for nep formation. It was developed at the North Carolina State College School of Textiles. under a contract with the U. S. Department of Agriculture, to predict the nepping potential of cottons.
The use of a standard-weight test specimen does not necessarily produce a standard weight web. There may be considerable differences in this respect among different cot tons. For each of eight cottons tested, the web weight and log of neps per grain increased with increase in specimen weight in the region tested between 17.5 and 27.5 grains in clusive, the increases being linear with no indication of curvilinearity. Since evaluations are based on comparison of the webs with appearance standards, the production of a constant weight web in the test is believed to be necessary. The possibility of controlling web weight by consideration of some readily determined property such as Micronaire reading or Fibrograph upper half mean length, or a combination of these, appears promising. Two simple equations have been derived for determining the specimen weight to use for a fixed web weight—one based on Micronaire reading and the other on upper half mean length.
Good correlation was found between the log of neps per grain and the photographic standards when the web weights were approximately constant. The regression curve above Grade 1 was essentially a straight line. Neppiness stindards following a regular progression can be obtained from the present photographic grades by adding another grade between the present Grades 1 and 2.
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