Work of any mountain mining enterprise is inevitably shown to passages of mountain developments. Thus process of digging is characterized by difficulty of ventilation of deadlock development. For maintenance of parameters of a miner atmosphere in a deadlock face fans of local airing, centrifugal and axial are established [1].
Mine fan installations of the main airing are intended for systems of mine ventilation of the main airing developments of mines and mines and equipments of an operating mode (submission and pressure), the control of temperature of bearings, the equipment remote and automated management, protection and the signal system, the complete set of means for reversion an air jet and transition from the working fan on reserve, the main thing bringing and ventilating channels, building constructions (buildings, the bases, diffusion, mufflers of noise consist of working and reserve fans with the electric drive, starting controller).
2 CONDITION OF A QUESTION FOR TODAY
The mine ventilating network has continuous indignations of the charge of air which have the complex structure caused by presence of different sources of indignation. Research shows, that mining consumption the charge of air basically has indignations of high-frequency stationary indignations of the charge (pulsation of a current), caused by turbulent current of air on mountain developments. Frequency of a pulsation of a turbulent stream is within the limits of 0,25-4 Hz, the amplitude of a pulsation of a high-speed stream does not exceed ±25Pа [2].
On the basis of it it is possible to draw a conclusion, that at system engineering regulation it is necessary to carry out management on revolting influence of the third type, thus for improvement of quality of management to consider presence of indignations of the first and second type.
Thus, it is possible to draw a conclusion, that the most comprehensible are systems of regulation by turn blades ON and under scheme АVК. Considering, that at installation of system AVK much greater expenses are expected, for the further consideration we accept a way of regulation by change of a corner of installation of blades.
3 REVIEW OF AVAILABLE AND PLANNED RESULTS
3.1 The general data on radial (centrifugal) fans
Radial fans represent a spiral casing with the driving wheel located inside at which rotation, air getting in the channel between it blades, moves in a radial direction to periphery of a wheel, is compressed and under action of centrifugal force is rejected in a spiral casing and further goes to an exhaust outlet. They are capable to move air on air lines on significant distances and develop pressure up to 12кPа [3].
Depending on purpose of the fan, blades the driving wheel make bent or back. The quantity blades happens various. Application of radial fans with blades, recurved allows to save the electric power on 20%, and fans with blades bent forward reach demanded result under the charge and a pressure of air, borrowing there is less than place and creating less noise. Radial fans are issued with cignt by positions of a casing. Apply fans low (up to 1кPА), an average (up to 3кPА) and high (up to 12кPА) pressure.
Variants of position of the case of radial fans are presented in figure 1.
Figure 1 – Variants of position of the case of radial fans
3.2 Analysis of technological process of airing as object of automation
The system of airing is intended for maintenance of mine with air in quantity which is necessary for maintenance of an operating condition of miners in developments at existing parameters at existing parameters of a miner atmosphere [4]:
gas evolution;
a dust content;
allocation of heat;
humidity.
The system of airing of modern mine includes main ventilator installations, fans of local airing, callorifer installations, ventilator a network, devices of distribution of air streams, devices of the control of parameters of a miner atmosphere and ways of communication.
The problem of automation of airing of mines is reduced to submission and distribution on developments of such quantity of air at which the set duration of faces is provided, adhering to safety rules and sanitary – hygienic norms and optimum operating modes ventilator installations are supported. Features of underground technology of dredging of minerals put forward this problem up to of some the most important problems of mining [5].
It is necessary to note, that, according to operating, 60% of reversive productivity should be provided in each of underground developments; hence, in view of specificity air distribution in mines – fans, for performance of the specified requirements in a reversive mode, should give 100 and more percent from a direct mode that axial fans can provide only, reversion turn blades the driving wheel on a corner 120 from minimal.
Reversion axial fans, as is known, it is possible in two basic ways: 1 – without change of a direction of rotation; 2 – with change of a direction of rotation. At reversion with change of a direction of rotation (without turn blades the driving wheel) diffusion a lattice" the fan becomes "convergent", blades the driving wheel (РК) "works" as a back edge forward, curvature of a structure лопатки becomes return ("unnatural") – therefore the efficiency of lattice РК and the fan in a reversive mode sharply falls can provide no more than 75% of a direct mode.
At reversioned axial fans without change of a direction of rotation by turn blades РК up to a corner 1350 (т. е. On 1200 from minimal, that is realized in our development on fans of a series IN), 100% and more from productivity of a direct mode can provide the fan.
At reversion one of trial fans VO-21K (first of working machines new of some a series IN) is received by us productivity of a reversive mode within the limits of 94–96 % from a direct mode for 40 with. Without a stop of the fan [6].
It is necessary to consider not only depth, but also reliability reversion productivity which ways of increase are certain by experts as: 1 – a possibility of inclusion of devices reversion jets on the move the fan; 2 – an opportunity of approbation of devices reversion repeated inclusion at check; 3 – reduction of number of consistently connected elements in the device реверсирования etc.
Lower parameters of reliability reversion in comparison with machines of WATERS will have installations with fans VDK etc. Each of them has on two electric drives, accordingly and on four high-voltage distrebuting device and Item which are switched (reversing) at reversion the fan.
1. Ушаков К.З. Аэрология горных предприятий. Недра, 1987г.
2. Автоматизированные системы и средства управления производственными процессами в угольной промышленности. Труды института, выпуск XIII. М., 1973.
3. Гейер В. Г. Шахтные вентиляторные и водоотливные установки. Недра, 1987г.
4. Батицкий В. А., Куроедов В. И., Рыжков А. А. – Автоматизация производственных процессов и АСУ ТП в горной промышленности. – М.: Недра, 1991. – 303 с.
5. Технические средства автоматизации в горной промышленности./ В. И. Груба, Э. К. Никулин, А. С. Оголобченко. – Киев: ИСМО, 1998. – 373 с.
6. Н. Н. Петров Об экономичности, стоимости и металлоемкости вентиляторных агрегатов // ФТПРПИ – 1988. – №4. – с. 66–72.