CC BY
26
Fig. 2. Changing the temperature of the concrete - t, °C and temperature voltage - ct the cross section of the structure (on teffect = 40 °C and time 16 00 hours)
References:
1. Ashrabov A. A., Zaytzev Yu. V. Elements of fracture mechanics of concrete. Tashkent: O'qituvchi, 1981. - 238 p.
2. Khodjaeva Z. Sh., Khodjaev A. A. Thermo-stressed condition of flexural reinforced concrete elements under complex thermal-climatic impactions allowing for nonlinear deformation of concrete. - Tashkent, 2015. - P. 205.
Xudoyberdiyev Tolibjon, professor of the Department
Muradov Rahimjon, PhD in Technique, the Faculty of Agro-engineering, Agricultural Institute of Andijan, the Republic of Uzbekistan
E-mail: [email protected]
Providing with uniform soil covering of the scattered seeds of wheat
Abstract: In article the theoretical analysis of possibility of maintenance seal the scattered seeds of wheat is resulted by uniform thickness of the soil received as a result of formation of furrows.
Keywords: the open space, the special installation, the new technology, an irrigated flute, crest soils, hiller with wings, a surface, a return proportion.
The essence of offered new technology consists in providing uniform covering with the soil received at formation irrigating fur-rower, wheat seeds.
It is known, that reception of uniform shoots of seeds depends not only on quality irrigating furrower [1, 181-184], but also on uniformity covering seeds soil. This question is still insufficiently studied [2, 361-390].
For realization of the given problem it is offered to establish working bodies on beam parallelogram the mechanism. In fig. 1 - drawing the scheme parallelogram the mechanism, the working bodies established on it and forces operating on them is presented.
These forces are the following: 1 - parallelogram the mechanism; 2 - basic wheel; 3 - furrower; 4 - adaptation for leveling soil;
Fig. 1. The scheme for studying of uniform
♦ Pj N^ — reaction of resistance of soil to rotation of a basic wheel and normal reaction, N;
♦ Pp — initial effort of a spring parallelogram the mechanism, N;
♦ m — weight parallelogram mechanisms with working bodies, kg;
♦ g — acceleration of free falling, m/s 2;
♦ Rz, Rx — horizontal and vertical forces operating on fur-rower, N;
♦ Fz, Fx — the horizontal and vertical forces operating on spreader of soil, N.
Condition of a static balance, we will write down in a following kind:
( r;+F; ) tgan -(R:+F: ) - mg+hm CB (1+ma) - p;=o ,(1)
where R;,F;, R;,F; -Rx (t),Fx (t) and Rz (t), Fz (t) . Average values of forces;
A — deformation of soil from action of a basic wheel at static
cm
balance of working bodies, m;
Cn — specific elasticity of soil, N/m 2; In — width of a basic wheel, m; ^ — resistance factor rolling a basic wheel; an — a corner of a longitudinal inclination parallelogram the mechanism.
Fluctuation parallelogram the mechanism at movement is influenced by physic mechanical properties of soil, quality of preparation of a field to crops and other factors. For definition of degree of influence of various factors on depth of occurrence of working bodies in soil and uniformity covering on a thickness it is necessary to work out the movement equation on a longitudinal surface. With the account of that at unit work the certain layer of earth of a furrow
movement furrower and spreader soils
on which seeds are scattered is leveled [1, 181-184], we accept following conditions:
1. The sowing unit moves with invariable speed.
2. We neglect forces of a friction in hinges parallelogram the mechanism in view of their insignificance.
3. Force from weights ofworking bodies and parallelogram the mechanism are enclosed to the centre of an axis of a basic wheel.
4. Influence of rectilinear and angular fluctuations of a tractor on depth of occurrence of working bodies in soil and a thickness of scattered soil on a furrow surface is not considered.
5. Basic wheels move without a separation from a soil surface, i. e. the condition: mg + Rz + Fz >(RX + Fx) tgan [3, 114-116] is constantly satisfied.
At performance of these conditions depth of occurrence of working bodies changes depending on change of depth of occurrence of a basic wheel in soil.
Considering the above-stated, oscillatory process of a basic wheel (fig. 1) it is possible to express as follows:
mZ = N - mg-(Rz + Fz) + (Rx + Fx + Px) tgan -Pp. (2)
If to accept Px = [iN z, in that case
mZ = N - mg-(Rz + Fz ) + (Rx + Fx) tgan + -tgan - Pnp; (3)
or:
mZ = N (1 + vtgan) - mg+ Fz) + (Rx + Fx) tgan -Pp, (4)
where Pp — effort of a spring parallelogram the mechanism, N. At static balance the mechanism:
Pp = P°pt. (5)
If to take into consideration that force Nz is proportional to change of deformation of soil it is possible to write down [1]:
N = N + N. (6)
z y c K /
At static balance of working body:
N = A C B;
y cm n '
N = 0.
At lifting of working body (a basic wheel) on height Z: N = 4 CB - Z CB = C • B (A - Z);
y cm n n n cm
N = Z-e ■ B ;
(7)
(8)
(9) (10)
or:
Ny = Nc = At-C • B - ZCB + Z -en ■ B. (11)
And at movement:
P = P° + ZC , (12)
np np h ' v /
where C — elasticity of a spring, N/m.
Considering expressions (6)... (12) we will receive the equation of fluctuation of a basic wheel depending on forces R , F and R , F:
-T O xf x z z
mZ =
(At- Z )C - Z en B (1 + ^tgan )-mg-( + F )-
(13)
+(( + F) tgan+ ZCn). Considering, change of forces R , F and R , F under the har-
cv O xf x zf z
monious law, we will receive:
(Rx + Fx )(t) tgan -(Rz + Fz )(t) = ( + F) tgan -
x x „ " * * x x n (14)
+ F") + £[(AR" + Fnx) tgan - (AR* + AFz )] • cosnat,
where R", F", R",F" - Rx (t),F (t) and Rz (t),Fz (t) average values of forces;
AR;, AF; and A Rl, AFnz - Rx (t), Fx (t) and Rz (t), Fz (t) Amplitude of variable making forces;
n =1, 2, 3 .... ni — numbers of harmonics; co = AR;, AF ; and A Rl, F* - frequency of change of forces, s1; Substituting corresponding values of sizes in expression (13), we will receive:
mZ= (At-Z)Cn -Zen B(1 + ^tgan)-
-mg - ( + F" ) tgan - (Rz + F" ) + (15)
+È[('ARnx + AFnx) tgan -(AR" + AFnz)] • cosnat -( + ZCH).
Considering, that the sum (15) sizes entering into the equation from the equation ofstatic balance (1) is equal to zero, we will receive:
m'Z+ BenZ(l + /utgan) + (CnB + Ch )Z -(1 + ^tgan) = = £ [(ARnx + AFnx ) tgan - (AR* + AFnz )] - cos not;
(16)
Z +-
'BU Z+&Z+ÇÀ SZ =
m
m
= — Y 17AR " + AF") tga -ÍARZ +AFz)!•cosimt,
m n-iLV n n n n n / J
(17)
where e = 1 + y tga .
It is considered, that expression (17) is the non-uniform differential quation of the second order. It expresses fluctuations in a vertical plane of a basic wheel, furrower and spreader soils. Its decision is possible in a following kind [4, 648].
Zx = Z1 + Z11, (18)
where Z 1 — the common decision of the left part of the equation, expressing free fluctuation ofworking body; Z 11 — the private decision of the equation expressing compelled fluctuations under the influence of forces A Rl, A F* and A Rzn, A Fz.
In the presence of force en ■ BZ (l + ¡J.tgan) in the equation, free fluctuations of considered system quickly fade, and then pass in a phase of the compelled fluctuations.
The decision of the right part of the equation characterizing compelled fluctuations ofworking bodies has the following appearance (19):
1 ni [(ARnl + AFnl) tga - (AR; + AFnz)] • cos (neat - 5 )
Z (t) =
m n-i
Here:
(CB + C )e m
8 =-
-( na) ■ B-s(n-a)
e-t
m
-( n-a)
(C - B + C ) e- m(na)2
(20)
^e condition for uniform depth and a thickness seal the scattered seeds have the following appearance:
Amai< 0.5 -Ah, (21)
where A — the maximum amplitude of the compelled fluctua-
max £ £
tions of working bodies; Ah — extremely possible deviation of depth and a thickness seal seeds.
Considering a condition (21) we will receive following expression (22):
^ Ê
m n-i
[(AR* + AF; ) tga - ( A Rl + AFz )]
-< 0.5 •Ah.
(C B + CH )
m
-( na)2
m
•( n-®)2
This inequality depends basically on elasticity of a spring parallelogram the mechanism.
Accepting Ah = 1 the sm. [2, 361-390] and solving an inequality (22) at following values of components is comparable the received result with 0.5 Ah:
C = 1700 N/m2; Bn = 0.12 m; Bn = 51200 Ns/m2; CH = 2000, 3000, 4000, 5000, 6000 N/m; ARxn = 300 N; AFnx = 120 N; ARzn = 50 N; AFz = 30 N; m = 81 kg; ca = 2 s-1; an"= 200; n= 0.3; n = 1; s = 1 + tga n = 1.11.
Values A depending on elasticity of a spring are presented
max r o 1 r o r
on fig. 2.
Fig. 2. Dependence of amplitude of compelled fluctuations Amax on elasticity of spring CH
Apparently, at CH = 5 kN/m it is had Amx = 4.8 mm. Thus, accepting Ah = 1 sm. we will receive Ah > Amax, (t. c. 5 > 4.8 mm), that correspond to condition Amax < 0.5 • Ah.
On the basis of the above-stated possible to draw following conclusions: at Cn < 5 kN/m the amplitude of fluctuations exceeds admissible value Ah, and at Cn > 5 kN/m the increases elasticity of a spring and lost its springing properties.
References:
1. To'xtaqo'ziev A., Meyliev A. X. Ekish egati chuqurligini bir tekisligini ta'minlash "Mashinalar texnikasining hozirgi zamon muammo-lari". - Toshkent, 2004.
2
s
+
or:
2. Xlopkovodstvo Uzbekistana za 50 let. Spravochnik/Pod. red. T. T. Zinina. - Tashkent: Uzbekistan, 1967.
3. Osnovi planirovaniya eksperimenta v selskoxozyaystvennoy mashinax RTM 23,2.36-73. - M.: VISXOM, 1974.
4. Augambayev M. I., Trekov Yu. I. Planirovaniye eksperimenta v nauchnix issledovaniyax po mexanizatsii selskoxozyaystvennogo proiz-vodstva/Pod. red. G. M. Rudakova, V. T. Yangiyo'l. - 1984.
Erkinov Zokirjon, research associate - the competitor, Tashkent institute of textile and light industry, Republic of Uzbekistan
Jumaniyazov Kadam, doctor of technical sciences, professor, Tashkent institute of textile and light industry
Parpiyev Habibulla, candidate for technical sciences, Namangan engineering texnological institute, Uzbekistan
Fayzullayev Shavkat, candidate for technical sciences, Tashkent institute of textile and light industry E-mail: [email protected]
The influence technological parameters on the physical and mechanical properties twisted yarn
Abstract: The article contains results analyzes and experimental study on the techniques and technology of production and torsional mechanical properties developed on different yarn twisting machines. And also, presented a new design of the twisting equipment, which allows you to increase productivity, improve the quality of a multi-twisted yarn with a uniform distribution of twist.
Keywords: twist, twisted thread, ring twisting machines, experiment, spinning and twisting machine, spindle, double torsion, range, physical properties, equipment for twists.
Manufacture of textile products based on many years of experience in processing natural fibrous materials. Extensive scientific generalization of the experience to identify the physical nature of the phenomena occurring with fibers, yarns and half-made goods in certain passages of the process, have been producing since 1930.
Therefore, the development of a new range of products, new processes and machines before the optimal solution will be found, we have to spend a large amount of experimental work1 [1].
The properties of the yarn, thread, fabrics depends on the interaction of many factors and in particular on the geometrical forms of the product and methods of its formation. Studies of the interaction between factors, such as, determining strength parameters thread, it is necessary to examine its structure is limited, mainly the establishment of formulas depending on the strength of the twisted yarn made of natural fibers on the degree of twist and the properties of a single yarn.
Production of twisted yarn — consuming and expensive process, so reducing labor costs and increasing production efficiency — one of the minor problems in the textile industry.
Basically, the experimental work was carried out for chemical staple fibers and natural in Russia and foreign countries to study the structures of yarn and twisted yarn with the influence of the properties of the fibers.
The scientists of the Tashkent Institute of Textile and Light Industry and Namangan Engineering — Institute of Technology are working on research projects for the study and improvement of techniques and technologies textile materials, which leads to an increase in the range and production of fabrics made from twisted yarn.
To study the inherent properties of twisted yarn on separate transitions and comparing process twisted art authors experimental work on a large volume.
Single yarn, usually has an unstable structure and different structure in their physical properties, which negatively affects the quality of her performance. The utilization of fiber in a single yarn strength, determined by the ratio of the relative breaking force relative to the yarn power properties of fiber's, no more than 45-50 %. There are various reasons: the presence of weak points in the yarn where the number of fibers in cross section is 1.3-1.4 times smaller than the ratio number of them derived from the linear density yarn and fibers relationship, the fibers have finite length and etc. [2].
For developing, the twisted yarn on ring twisting machines dry method K-83, spinning and twisting machine PK-100-M4 and Two-For-One-Twister machines on firm «Volkmann» VTS-08 was used single-stranded cotton yarn of different assortments — 20, 25 and 29 tex.
Firstly was developed twists on structure 20 x 2, tex 20 x 3 a ring twister machine dry method K-83 from the single-stranded cotton yarn 20 tex and 25 prepared in the spinning «Truetzschler» company equipments. Also, twists of the same structure were produced on Two-For-One-Twister machine VTS-08. For the doubling of threads 2 and 3 in mixing can frame used TV-150. On spinning and twisting machine PK-100-M4 worked out the structure of twisted thread 20 x 2 tex.
Physical and mechanical properties of single yarns and twisted yarns are shown in tables 1 and 2.
