| Abstract: | Conclusions -- The basic factors and principles which determine the stability of processes of preparing and processing yarns have been
examined. It has been shown that it is advisable to use the figure for the mean length of a break-free yarn section as a general
characteristic for technological stability for yarns of various types and various processes.
-- Application of reliability theory shows that the mechanical properties of yarns (load-bearing ability) and technological
reserve in mechanical properties (reserve coefficient) have basic importance to ensure stability of technological processes.
Thereupon, one should take into account the change in yarn properties under the effect of external actions under the conditions
of technological processes.
-- The effect of structure heterogeneity and yarn defectiveness on nonuniformity in properties and yarn serviceability in
technological processes has been analyzed.
-- Various methods of predicting yarn serviceability which are based on evaluating both their breaking characteristics and
also of complex quality criteria have been generalized and analyzed.
-- New criteria for predicting the serviceability of yarns have been proposed: the scale coefficients of the breaking characteristics
for the case of single stretching actions and a complex durability figure for the case of repeated actions of stretching and
bending with abrasion. These criteria are particularly important for evaluating the serviceability of yarns with specific
mechanical properties.
-- The connection between complex quality criteria and the serviceability of yarns with the stability of technological processes
(breakage) and the quality of the textile materials obtained has been examined.
The author remembers with thanks Prof. A. B. Pakshver, who has helped greatly in discussion of questions about the serviceability
of yarns in processes of preparing and processing them.
Translated from Khimicheskie Volokna, No. 2, pp. 45–46, March–April, 1991. |
