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to the feeder-distributor, a uniform distribution of raw cotton along the length of the screw conveyor and the uniform distribution of raw cotton during loading and unloading in the volume of the chute. These factors relate to the capacity of the installation.
Taking into consideration the above mentioned conditions, we proposed a feeder-distributor with new structure, which conveyor
screw is tapered with variable pitch, decreasing the length of the feeder-distributor.
Tapering and changing of the step of the screw conveyor is selected so that a decrease of cotton intensity along the length of the screw conveyor decreases proportionally to the diameter and pitch that provides uniform distribution of cotton to the sections of the device to keep natural properties of raw cotton.
References:
1. Milohov N., and others. Primary cotton treatment. - M: - 1959, P. 373-377.
2. A utility model patent. FAP № 00520 «Storage for fibrous material" - 29.01.2010, M. T. Hojiyev, A.J. Jurayev, H. K. Rakhmonov, M. E. Ruzmetov.
3. A utility model patent. FAP № 00514 «Devices for supply and distribution of the fibrous material" - 21.12.2009, M. T. Hodjiyev, A. J. Jurayev, H. K. Rakhmonov, M. E. Ruzmetov.
DOI: http://dx.doi.org/10.20534/ESR-16-9.10-208-210
Ruzmetov Mansurbek, Senior scientific employee-researcher, Tashkent institute of textile and light industry (Republic of Uzbekistan).
E-mail: [email protected] Xodjiyev Muksin,
doctor of technical sciences, professor, Tashkent institute of textile and light industry (Republic of Uzbekistan).
E-mail: [email protected]
Development of the device for loading and distribution of raw cotton into the closed storage
Abstract: Based on the results of the study of the loading and distribution of raw cotton into the closed storage an improved cotton feeder-distributor for closed type storages is introduced in this article. The proposed feeder-distributor is based on a conical screw with variable pitch to ensure uniform supply and distribution of feed raw cotton over the entire length of the screw and the volume of the closed stores. The results of its testing at production conditions showed that using of this setting can increase the duty cycle of raw cotton closed storage, to ensure the complete mechanization of the loading process and a uniform distribution of raw cotton into the closed store, as well as the automation of these processes.
Keywords: loading process, screw, conical shape, uniform supply, load factor, uniform distribution, efficiency, natural properties.
In order to develop the structure ofraw cotton distribution device into the closed storage the following mandatory conditions are necessary to provide:
— High performance of cotton loading to 25-30 m/h, which must match the capability of combined devices (XPP and the CLP-650);
— Uniform supply of raw cotton for the entire length of the closed storage.
Considering the above conditions, we have developed a screw feeder-distributor with periodically opening groove [1; 2].
This device provides a uniform raw cotton distribution by conveyer length and raw cotton natural features keeping.
Conveyer's screw is performed by conic variable step, reduced with screw's length. The conicity and changing of screw is selected in such way when raw cotton weight is minimized proportional diameter and step which provides uniform allocation to the sections of the device.
The device is clarified by drawing: picture 1 demonstrates general type of the device, picture 2 shows type "A" and profile of "B-B" cam.
The device 1 comprises a shute formed in the lower part of the movable sections 2, 3, and mounted in the upper part of the shute
4 taper screw with decreasing pitch, the difference of diameters of the screw 4 is selected equal to the bases of the cone is not more than 100 mm.
The value between the maximum and minimum diameters of the screw and the steps is selected from the condition of the size of the average value of the diameter of a lump of cotton (not more than 100 mm) in the device.
The screw 4 is connected with the shute 1 by brackets 5. On both sides of the chute 1 driving shafts 6 are mounted by brackets 7, 8 on the top of the chute 1, and the driving shafts 6 are forced on with component cams made of bases 9, 10 and worn they rubber rings 11 and 12 and fixed on the profile bases 9, 10 with a special glue, all of which interacts with the cantilever arm 13, 14 of one section of section 2, 3 of shute 1, mounted on hinges 15, 16.
The device operates as following. Raw cotton located in the chute 1 is moved around along the shute 1 with revolute transitional moving of the shute 4. The lower part of the shute 1 is designed as a movable sections 2 and 3. Each section consists of two hinged parts having overhanging arms 13, 14, which cooperate with the rubber rings 11 and 12, the cams 9 and 10 and in accordance of the condition of the profile rubber rings 11 and 12 change relative positions
Development of the device for loading and distribution of raw cotton into the closed storage
concerning to the screw 4, for example, are opened or closed. Profiles of rubber rings 11, 12 and cams 9,10 are chosen so that while opening of one section of the shute 1others are closed. It supplies raw cotton in a given place at a given time.
During the opening of the corresponding pair of sections 2,
3 is unloaded from cotton device. Thus, in all sections of the screw conveyor according to a certain law occurs alternately opening and closing sections, and thus the discharge of the device. To ensure the uniformity along the length of raw cotton of the screw 4, the latter is conical with decreasing lead.
In the beginning of the movement of raw cotton by screw 4 seed cotton fallout from the first section, and further, raw cotton is compacted both vertically due to reducing of the diameter of the screw
4 and the screw along the length of the reduction step. In the following sections of cotton fallout will be the same (by volume and weight) as in the previous sections.
The proposed design is achieved by multiple repetition of the distribution process, which significantly increases the uniformity of the paved layer. This ensures uniform distribution of the raw cotton within the repository throughout its volume.
The proposed plant has a working length of 6 meters with the possibility of adjusting the geometric parameters of links and gaps.
The chute consists of a two-arm arcuate funnel. The first arm length is L1= 25 mm, the second arm — L2 = 45 mm, the
width is 70 cm/To ensure a smooth and timely raw cotton fallout from the chute the inside parts of the crater made of smooth metal steel. The number of chutes in the construction consists of 6 pieces. Screw conveyor chute to the carriage 15 attached via mm steel wire. From the top of the chute it contacts with the cam. Upon contact with the cam portion cut tipping occurs that leads to opening of the chute and unloading cotton located inside. For a simultaneous opening of chutes contacting cams are located in opposite directions in the same positions. The diameter of the cam is 250 mm. Right side is trimmed with metal, resistant to abrasion. There is a cut with an angle of 60° opening. Cams are headed on separate shafts. The shaft supporting a cam mechanism is made from steel with diameter of 45 mm and the length of 6,2 m.
To secure the cam gear while cornering, and unwanted shift in the shaft the key way is provided.
The selected design features of the developed device for loading and distribution of raw cotton provide optimal conditions for the supply and distribution of cotton across the length and volume of the closed store, which in turn provide the download complete, uniform layer.
Testing of the new device performance for downloading and distribution of raw cotton in the closed storage was carried out in Kagan JSC "Oltin tola", Bukhara region.
Figure 1. General view of the feeder-distributor
1 - the chute; 2.3 - section of the device; 4 - the screw; 5, 7, 8 - arms; 6 - driven shaft of cam; 9, 10 - cams; 11, 12 - rubber rings; 13, 14 - cantilevered arms; 15, 16 - hinges
Figure 2. View on the "A" feeder-distributor and the cut of "B-B" cam
When the device was placed into the closed storage their basic dimensions were accounted. So, taking into account the size of a typical warehouse of 54 to 24 meters 2 sets of devices were placed there. Developed storage scheme with new devices for loading of raw cotton in comparison with existing analogues has a positive effect on the following parameters:
1. Factor of storage loading is 0,90-0,96.
2. The high level of mechanization of the processes associated with the downloading and distribution of raw cotton for the entire volume of the closed stores.
3. Ability to automate processes and manage the download and delivery of raw cotton in the distribution area.
This scheme of loading into the storage and the device for its implementation is recommended for widespread use in the cotton industry to ensure the preservation of the natural properties of raw cotton.
References:
1. A useful model patent. FAP № 00520 «Storage for fibrous material" - 29.01.2010, M. T. Hodjiev, A. J. Jurayev, H. K. Rakhmonov, M. E. Ruzmetov.
2. A useful model patent. FAP № 00514 «Devices for supply and distribution of the fibrous material" - 21.12.2009, M. T. Hodjiyev, A. J. Jurayev, H. K. Rakhmonov, M. E. Ruzmetov.
DOI: http://dx.doi.org/10.20534/ESR-16-9.10-210-212
Saatova Nodira Ziyayevna, Tashkent institute of design, construction and maintenance of automotive roads E-mail: [email protected]
Dependencies to determine the measure of damage and calculation of residual life of reinforced concrete superstructure, exposed to salt corrosion
Abstract: In this paper we consider the current method of determining the measure of damage of concrete and reinforcement. The proposed dependence measures of damage, convenient for use in predicting the life of structures superstructures. The practical method of calculation determination of residual resource of the exploited superstructures developed. The main source of data for calculating the residual life are the parameters defined by the technical diagnosis.
Keywords: measures the damage, resource forecasting, exhaustion bearing capacity of the structure, corrosion of concrete and reinforcement, the remaining service life, load-bearing capacity.
Forecasting resource of intense machine elements and structures [1; 2], reinforced concrete and steel bridge spans [3; 4; 5; 6] are now used the main provisions of the theory of linear damage accumulation [7; 8].
In [10-12] considered a practical way of determining the degree of salt corrosion in the concrete, the use of which will be possible to establish the actual thickness of the concrete, exposed to salt corrosion; It developed a method of estimation of influence of salt corrosion of the concrete work and valves; calculation method for determining the measure of damage of concrete and reinforcement. The proposed permit depending on the results of the survey to determine reliably the load span structures, suitable for use in predicting the resource superstructure.
Thus damage caused by external impact during the considered time independent of the load history, and they can be summed with previous injuries. The value of the degree of damage is estimated as 0 < Y < 1, at the beginning of loading Y=0; at the moment of exhaustion bearing capacity of the structure Y=1.
The accumulation of damage over time is described by T t
Zt, =1 (1)
For structures operating under cyclic downloaded
t— = 1 (2) tf Nt
where n. - number of cycles at a uniform loading; N. - number of cycles to failure.
Y - measure damage to any point in time
t t V =T ^ ' t=0 T
In the case of non-linear voltage uploading a
T dt
= Í-
' 0 T (a)
(3)
(4)
On the basis of (3) in [5; 6] proposed to determine the dependence of the resource elements of metal bridges.
V. P. Chirkov [9] proposed a mathematical model for resource prediction of reinforced concrete bridge spans on the basis of these provisions.As a measure of concrete damaged by exposure to multiple repeated loads accepted the change of the transverse deformation coefficient Vand with this in mind, the dependences for determining resource superstructures.
In the work of R. Mamajanov is described the degradation process and development of cracking in the concrete of the compression zone spans used basic parameter fracture mechanics - stress intensity factor "K". The dependences for the description of the "K" in time, when repeatedly re-loading.
In the works of the above story loading is taken into account, the characteristics of loads and their statistical dispersion.
However, it should be noted that the use of measures to assess the damage for practical calculations are complex and require the presence of large statistical data.
