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Efficiency wet-heat processing due to the use of composite materials
References:
1. Gavrilov I. A., Rakhimov T. G., Puziy A. N., Nosirov Kh.Kh., Kadirov Sh. M., "Цифровое телевидение", «Тор Image Media» - Tashkent. - 2016. - 400 p.
2. Kubasov D., Vatolin D. "Review of motion compensation methods", URL: http://cgm.graphicon.ru/content/view/76/65
3. Ian Richardson "Video coding. MPEG-4 - next generation standard", - Moscow, - Vol. "Technosphere", - 2005.
4. Gavrilov I. A., Otto S. E., Kim M. V., "Improving the efficiency of the compression of the video stream based on the zoom image", Proceedings of the international conference "Actual problems of development of info-communications and the Information Society". -Tashkent. - 2012, - P. 157-162.
5. Gavrilov I. A., Rakhimov T. G., Analysis of methods and problems of TV images compression. Proceedings of the Republic science technician conference "Axborot texnologiyalari va telekommunikatsiya muammolari", - 21-22 April. - 2011, - Tashkent, - P. 63-67.
6. Dirac Specification Issued: April 2, - 2008. URL: http://diracvideo.org/download/dirac-research/documentation
DOI: http://dx.doi.org/10.20534/ESR-17-1.2-221-222
Nutfullayeva Lobar Nurullayevna, Research associate-the competitor, Bukhara Institute of Technical and Engineering, E-mail: barno.professorov@mail.ru Tashpulatov Salih Shukurovich, doctor of technical sciences, professor, Tashkent Institute of Textile and Light Industry, E-mail: barno.professorov@mail.ru
Efficiency wet-heat processing due to the use of composite materials
Abstract: The article describes the tools and technological methods of processing parts of garments using composite materials; It shows the parameters of the wet-heat treatment. The recommendations on the choice of forming elements for the manufacture of garments items.
Keywords: wet-heat treatment, the composite material, the surface treatment, the matrix, glass cloth, glass mat, breaking load, elongation at break, hardness, wear.
It is known that the main parameters of the wet-heat treatment (WHT) is the temperature (°C), the pressure ofworking bodies (kPa), moisture (w), the exposure time of working tools (s). The choice of parameters depends on the WHT fibrous composition, density, color, kind of surface finishing materials of construction for the part of the product. Settings must satisfy the requirements of optimality, realistically achievable in the enterprise and economic requirements.
The requirement is optimal choice of such a combination of WHT parameters within certain ranges, which gives the best results of processing of products. The latest models of equipment for the WHT are equipped with computer software allows for processing at any of the available programs. These tools greatly facilitate the choice of rational combinations of the parameters of the WHT and open up the possibility of centralized management modes on all transactions. It should be noted that one of the important indicators of the quality of the WHT are to maintain the original physical and mechanical properties of tissues and products packages.
However, experience has shown that the methods used by the WHT and the proposed treatment regimens, even in the new, mod-
ern equipment fundamentally do not lead to an increase in the quality of processing of details of clothes.
Studies have shown [1-2] that the application of the existing regimes in the existing WHT equipment leads to a decrease in the basic indicators of physical and mechanical properties of fabrics and packet. It should be noted that indicators such as the breaking load, the abrasion resistance of fabrics and packet products lost their original values by an average of 20-30%.
This provision can be described graphically as follows [3]. The mutual arrangement of warp and weft in the fabric is defined by bending them, namely bending wave height of warp yarns (ho) and weft (h01) and correspondingly the length of their half-waves (lo and l01). The height of the bending wave is the distance between the location of the yarn layers of a system in a vertical plane when the warp and weft overlap (Figure 1). Bending length ofhalf-wave warp and weft threads in a single layer or in a layer of the multilayer fabric is determined by the corresponding horizontal distance between two adjacent threads in places of crossing strands in the opposite system.
*- d»
i 1 ho г
\ \
\ N ( л
) к S Vf V
« lo H
Figure1. The initial view of the tissue section to a wet-heat processing
Section 12. Technical sciences
If the fabric is exposed to temperature and pressure to plasticize the fibers with moisture, such a tissue surface will differ from the surface of the fabric having undergone not pressed at WHT due to structural changes.
Thus, in the WHT, i. e. under the influence of pressure, temperature and moisture acting as a plasticizer weaken intermolecular bonds filaments of fibers and yarns of the fabric are flattened, they take a different form. As a result, the transverse threads form tissue changes from a circular shape (Figure 1) is transformed into an
oval (Figure 2). In this case, the geometric figures tissue structure changed as follows: the distance between the edges of the threads S0 and S01 is reduced by flattening the original shape, the distance between the centers of the filaments l0 = l01 remains unchanged, the ratio between the initial diameter and large diameter oval d<D01, wave height bending filaments h0 <h01, the length ofhalf-waves C0 <C01, the angle between the axis of the lengths of half-waves is characterized by a decrease with respect to the initial state: ag<a0i> P0<fi01, thereby increasing the surface density of the tissue.
Figure 2. Type of tissue section after WHT
To determine the index of sustainability surveyed tissue tear chanical properties of the tissue after WHT and compression sig-after wet-heat processing and compression were also conducted nificantly influenced the tensile characteristics of the tissue. laboratory experiments on fabric tensile load by the standard The results of experimental studies on the physical and mechanical
method [4]. Changing the geometry and the physical and me- properties of the tissue before and after the WHT are listed in the table.
Table 1. - Summary table of the results of experiments on tissue breaking force and elongation at break
Fabric Name to the WHT (control) fabric after the WHT
on the basis of the weft warp on the basis of the weft warp
Breaking load (N) 239,3 168,6 164,2 135,2
Elongation at break 117,3 186,3 87,5 158,4
As shown by the analysis of experimental results, the value of the reference values of tissue tensile load to the WHT threads bases on average reaches 239.3 N, and in weft — 168.6 N, and for elongation figures are, respectively, 117.3 and 158.3.
Similar indices ofphysical and mechanical properties of tissues and WHT after pressing demonstrated that the magnitude of tensile load in warp yarns averages 164.2 H for weft — 135.2 NA in this case reduction properties on the indicator samples is 31, 4% and 19.8% respectively.
The same analysis was performed for tissue elongation. The value of the reference values of tissue elongation after WTO and compression showed that the value for the warp yarn is averaging 87.5 on weft — 158.4. In this case, the reduction properties of this indicator the samples is 25.4% and 14.9% respectively.
To improve the quality of clothing at the WHT transaction details by scientists of the Tashkent Institute of Textile and Light Industry, together with the Bukhara Technological Institute of Engineering and «OFS» by the specialists of the new press equipment airbags have been developed from the perspective of a composite material [5]. At the same time, the pillow was made on the mold
surface, the surface obtained by repeating parts of the product when lying on the plane. Thus, the opportunity to manufacture pillows press equipment for the majority of machined parts and components garment. This cushion is characterized by its lightness, low power consumption, mobility, efficiency, rigidity, strength, etc.
In the manufacture ofpillow presses used multi-material, fiber-layered structure consisting ofa plastic base reinforced with fillers having a high strength mechanical and thermal stress, resistance to moisture, etc.
Our research in the production environment of the company «OFS» in the manufacture of men's outerwear has shown that the proposed technological sparing regimens WHT operations using existing equipment have shown encouraging results.
Thus, on the basis of the above, it can be concluded that the factors and reasonable assumptions about the negative impact of the technological process of the WHT in conjunction molding and pressing onto the fabric in the manufacture of parts of garments have been identified on the basis of the research. It was found that for the purposes of improving the quality ofWHT operations using the power saving mode should be used cushion pressure equipment manufactured and composite materials.
References:
1. Tashpulatov S.Sh. The development of high technology resource-saving manufacture of garments. Abstract dis. ...Doctor. tehn. Sciences. - Tashkent: TITLI. - 2008. - 38 p.
2. Tashpulatov S.Sh. Highly resource-shaping technology and WHT clothing details. The book, publishing house "Science and Technology", - 2010, - 96 p.
3. Alimbaev E.Sh. The theory of the structure of the fabric. Tashkent, TITLI, - 2007. - 107 p.
4. Methodical instructions to the research and laboratory work for testing textile products. - T., - 2007, - 94 p.
5. Commercial agreement № 7-13. Improving the quality of garments in the process of wet-heat processing. Head: Nutfullaeva L. N. -Bukhara, BTIE. - 2014, - 171 p.
Stretching curved wooden frame-type elements "Sinch"
DOI: http://dx.doi.org/10.20534/ESR-17-1.2-223-225
Razzakov Sobirjon Juraevich, Associate professor, Ph.D, Head of Department Akhmedov Pakhritdin Sayfiddinovich, Senior teacher Chulponov Olimjon Gofurjonovich, Senior teacher Mavlonov Ravshanbek Abdujabborovich, Assistant teacher
Uzbekistan, Namangan engineering-pedagogical institute, department of Civil Engineering E-mail: sobirjonrsj@gmail.com
Stretching curved wooden frame-type elements "Sinch"
Abstract: Substantiated the influence of longitudinal forces on the stress state stretched-bent wooden elements of the building frame and update their bearing capacity.
Keywords: wood element, a skeleton wooden "Sinch", normal stress, axial force, bending moment, bending stiffness, stability, strength, dynamic impact.
When dynamic effects in the elements of column and "Sinch" wooden frame occurs repeatedly opening and closing knots. At the same time applied to the compressed elements of stretching and tension member to compressive forces. Furthermore the tensile and compressive forces from the walls in the frame having transverse loads. That is, the frame members are in position eccentric compression and stretching.
When calculating the compressed-bent wooden rods to apply the theory of boundary stresses, proposed by prof. K. S. Zavriev. In line with this theory, the bearing capacity of the wooden rod is considered to be exhausted at the time when the edge compression stress becomes equal to the calculated resistance. This theory gives a simple explanation. Since the rigidity of the wood element is not infinite, it is under the influence of bending moment flex. This centrally applied force now will have an eccentricity equal to the deformation of the wooden rod from the moment, and thus creates an additional point of the longitudinal forces, which increases the deformation of the rod, which leads to an even greater increase in additional torque during compression. Such a build-up of additional torque and deflections will continue for some time [1].
Normal stress (oc) in compressed-bent elements is determined by the formula
a= N / A + M /W (1 - N / Nk) = N / A + M / WL (1)
c ras q ras^- kr' ras ras~ 1 V /
Coefficient , taking into account the additional torque from the longitudinal force in the rod deformation applied at values from 1 to 0 and it is determined by the formula
$ = 1 - , hereNkr = ^RAbr
Nkr
And with the impact of vertically directed longitudinal forces, in addition to the bending moment acts centrally applied force, tensile compressed-bent wood element. Therefore, after the deflection element "Sinch" induced bending moment, the normal force will create additional torque of opposite sign and thus will reduce the total bending moment. At this time, stretched-bending elements are calculated without taking into account the additional longitudinal forces at the time of the wooden rod deformation by the formula (2) [2; 3; 4].
N MR a = — + < R
c A WR '
(2)
here Ant — sectional area of the net; Rr, Rt — calculated tensile strength and bending.
This formula can be applied to the wood of the 2nd and 3rd class, and the wood is 1st class, it does not match.
Based on the foregoing, it has been tasked to determine the normal stress with the additional point in the stretched-bent wooden elements. (see Figure 1) [2].
The applied tensile force forms a opposite moment to the bending moment on the lateral loads, ie, decreases the value of the total angular momentum and the formula takes the form of stress (3):
N M - N ■ f
a =±1L. +_q_r •/m" (3)
" A, W
nt nt
here Mq — moment, produced by shear forces q, fmx — maximum deformation of the rod; Wnt — net cross sectional moment of resistance; Nr — tensile longitudinal force; Ant — net cross-sectional area; <Jrj — normal tensile stress-bending.
As a result of the bending load q transverse bending moment is formed, as a result of longitudinal stretching force N additional bending moment is formed with a negative sign.
We form the expression for the total bending moment at the point x of the rod (4):
Mx = Mq - Nr • y (4)
In two (3) and (4) the above equations, there are three unknowns Ur i, y, Mx, it is necessary to find another additional equation. Any curve can be theoretically expressed as a number, which in this case must be quickly convergent and satisfy the boundary values. That is a trigonometric series in the following form:
y = fl ■ sinnx/l + f2 ■ sin2nx/l + f ■ sin3nx// +... Figure 2 shows the interpretation of this series. When balanced load enables the first term ofprecision equal to 95 to 97% [1]. Then, limited only by the first term of (5), we obtain:
y = f ■ sin(n x/l) (5)
However, the above equation has brought one more unknown f1.
