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Simplified formulas for use in establishing the relationship between the tension and strain of base threads and weft on a loom, taking into account their viscoelastic properties, are obtained. It is established that the relationship between the tension and strain of carbon and quartz threads may be described by equations from the nonlinear theory of viscoelasticity. [ABSTRACT FROM AUTHOR]

We have determined the optimal technological parameters for manufacture of parachute aramid fabric on looms of different designs. We have studied the effect of the basic operating parameters of the loom on the physical and mechanical properties of the fabric. We have established that the air permeability of parachute fabric can be considerably reduced due to buckling of the warp yarns when using droppers. We have worked up recommendations for manufacture of fabric with specified air permeability on a high-speed Dornier rapier loom, making it possible to improve the quality of the fabric and the productivity. [ABSTRACT FROM AUTHOR]

We present the results from calculation of the damage rate for carbon and quartz warp yarns in manufacture of combination multilayer hollow fabric. The results of our study have demonstrated analytically the feasibility of processing them on a loom. [ABSTRACT FROM AUTHOR]

An automated method of designing technology for manufacturing fabrics of defined structure was developed. An algorithm was developed for calculation of fabrics of defined structure in designing the technology, consisting of determining the properties of the fibres used (tensile and compressive viscoelastic parameters, durability parameters, resistance to wear and repeated loads, hemicyclic characteristics); determination of the coarse fabric structure phase; calculation of warp and weft tension during frontal battening based on use of the linear theory of warp thread fibre tension in the “warp roller—dropper” zone and the weft thread pinch tension based on the linear theory of viscoelasticity; estimation of the loom threading tension using long-term strength criteria; determination of the maximum possible rotation rate of the main loom shaft; calculation of breakage of warp and weft threads based on the assigned properties of the fibres. Software was created for designing loom manufacture. The manufacturing process for production of an important number of fabrics was designed. The basic process parameters for manufacturing fabrics were determined. [ABSTRACT FROM AUTHOR]

Statistical modeling showed that there can be important scattering in the spectral characteristics of the tension compensators (TC) used as warp thread tension stabilizers in winding on the warp roller due to statistical scattering of the values of the parameters. The statistical model of TC showed that statistical scattering is not only reflected in the type of the average frequency characteristic of the tensioner accumulator but is also a function of the ratio of the tensioner coefficients, in particular, the ratio between the natural frequency of its vibrations and the damping factor. If the scattering is LOW at a higher damping level, at a low level, the scattering of the frequency characteristics is relatively HIGH and can affect the nonuniformity of the thread tension, and this must be taken into consideration in synthesizing an automatic central system for controlling thread tension. [ABSTRACT FROM AUTHOR]

A measuring device is developed to replace devices used previously in order to more accurately measure the length of a bolt of cloth being woven on a loom. Knowing the actual weft density of the cloth, it is possible to reliably measure the length of the bolt by determining the number of weft threads in it. The measurement error in tests performed on STB-type looms is no greater than ±0.03-0.05 m for bolts up to 50 m in length. [ABSTRACT FROM AUTHOR]