Resulting from researches conducted to determine tension for para-aramid, meta-aramid, and carbon multifilament yarns during their contact with the operative parts of the weaving looms as part of the industrial fabrics formation process, we have found out that in threading areas the tension is increasing driven by variation of values of the friction forces in the contact area. It has been proven that tension degree of para-aramid, meta-aramid, and carbon multifilament yarns before industrial fabric formation area is influenced by (1) tension before cylindrical guide surface of an operative part, (2) radius of the cylindrical guide surface curve of the operative part, (3) contact angle between yarns and cylindrical guide surface of an operative part, (4) mechanical, physical and structural properties of para-aramid, metaaramid, and carbon multifilament yarns. It allowed (yet at the initial stage of design of technological process of industrial fabric formation) to determine para-aramid, meta-aramid, and carbon multifilament yarns tension before formation area depending on (1) form of threading line for yarns at the weaving loom, (2) mechanical, physical and structural properties of para-aramid, meta-aramid, and carbon multifilament yarns and industrial fabrics. The paper contains experimental research of interaction of para-aramid, metaaramid, and carbon multifilament yarns and cylindrical guide surfaces of the operative parts of automatic weaving looms. Based on experimental researches regression dependencies have been obtained between para-aramid, meta-aramid, and carbon multifilament yarns tension value after cylindrical guide surfaces of the operative part and (1) tension before cylindrical guide surface of the operative part, (2) radius of the cylindrical guide surface curve of the operative part, (3) contact angle between yarns and cylindrical guide surface of the operative part. Consecutive application of these regression dependencies allows to determine para-aramid, meta-aramid, and carbon multifilament yarns tension before industrial fabrics formation area. Analysis of regression dependencies allowed to find out values of technological parameters when para-aramid, meta-aramid, and carbon multifilament yarns tension before industrial fabrics formation area will be of minimum value. It will allow to minimize tension of para-aramid, metaaramid, and carbon multifilament yarns while manufacturing resulting in (1) yarn breakages reduction, (2) better productivity of weaving looms due to reduced stoppage time, (3) improved quality of manufactured industrial fabrics. Therefore, we can argue that suggested technological solutions are practically attractive. In view of this, it is reasonable to say that it is possible to directionally regulate the process of para-aramid, meta-aramid, and carbon multifilament yarns tension change while manufacturing industrial fabrics on the weaving looms through selection of values of guides’ geometrical parameters.

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The research of the systems of equations of quantities describing, respectively, 5 and 6 measurement cycles revealed the peculiarities of redundancy formation. It is proved that the normalized temperature T1 has the greatest effect on the measurement result for both systems. In addition, it was found that in both systems, an increase in the reproduction accuracy of the normalized temperature T1 (with a constant reproduction error of T2) does not lead to a significant improvement in the results. Due to this, it can be argued on the use of non-precision normalized sources to reproduce the temperature T1. However, an order of magnitude increase in the reproduction accuracy of both normalized quantities T1 and T2 also increases the measurement accuracy by an order of magnitude. Computer modeling confirmed that for the redundant measurement equation (11) at the ratio Т1=Ті(0.0005•Ті+1) in the range (10÷200) °С, measurement with a relative error (0.01÷0.00003) % is provided. When applying the redundant measurement equation (13), the accuracy increases to 0.0059 % only at the end of the range. Based on the results obtained, it was found that the accuracy of redundant measurements is influenced by the type of equation itself, not their number. Processing of the results based on the redundant measurement equation, by the way, ensures the independence of the measurement result from the influence of absolute values of the transformation function parameters, as well as their deviations from nominal values under the influence of external destabilizing factors. Thus, there is reason to believe that it is possible to increase the accuracy of measurement in a wide range by observing the ratio between normalized and controlled quantities

Studies of the effect of normalized radiation fluxes on the measurement result revealed the most influential one. The value of the normalized flow F0 was shown to have a greater effect on the relative measurement error than ΔF0. This allows investigating the relationship between the controlled Fx and the normalized flow F0. Experimental studies have confirmed that by a threefold increase in the normalized flow F0 relative to the controlled flow Fx, it becomes possible to increase the measurement accuracy in a wide range. In particular, it was found that at the flux value F0=0.16×10-3 W, it becomes possible to measure the controlled flow in a wider range Fх=(0.16×10-3÷0.97×10-3) W with a relative error of thousandths of a percent. The effect of the reproduction error on the measurement result under the condition of a threefold increase in the normalized flow F0 relative to the controlled flow Fх is shown. It was found that an increase in the reproduction error of the normalized radiation fluxes by 1 order leads to a narrowing of the range in which the value of the relative error tends to zero. It is shown that in the absence of a threefold increase in the normalized flow F0, an increase in the reproduction error of the normalized flows by 1 order leads to individual cases of reduction in the relative error to small-order values. The latter, by the way, applies to cases where the ratio between the normalized F0 and controlled flow Fx, as 3 to 1, is ensured. It is shown that the reproduction error of the dark flow does not affect the measurement result.Thus, there is reason to believe that it is possible to expand the measurement range, in which the value of the relative error is thousandths of a percent, even for 1 measurement cycle