SU1752697A1 - Suction method in extended shelters of grain conveyer lines - Google Patents

Abstract

The invention relates to the grain processing industry and can be used in other branches of the national economy to reduce explosive hazards. The method consists in the fact that before the product starts to flow, stable aerodynamic connections in the line measure the total inlet and outlet pressure of each piece of equipment and the pressure loss due to the leakage of each piece of equipment, as well as the total pressure at the inlet and outlet as a result of measurements, the value of the quantities characterizing the aerodynamic state of each piece of equipment and technological connections is determined, and then, by summing these values, the working th point transport-technological line and its parameters, and after the product is determined by the largest area and pressurizing them at excess pressure value at the operating point is reduced by chopping the first il minutes ustayoNky line additional aerodynamic bonds. 4 il. (Ls

Description

The invention relates to the field of the grain processing industry and can be used in other branches of the national economy to prevent explosions in the mining, metallurgical, chemical and other industries.

There is a known aspiration method, which means that the connection to the aspiration of individual equipment is carried out according to the standards specified in these recommendations and the connection of all equipment to the individual aspiration networks.

There is a known aspiration method, which means that the air is taken from the equipment connected by the technological connection by one point according to the standards established earlier.

The disadvantages of this method are as follows;

1) does not exclude dust emissions due to the fact that it does not take into account the connection of the equipment in terms of aerodynamic qualities, its connection and location in the TTL;

2) there are no reasonable standards for the aspiration of equipment, there is no record of the operation of equipment with a different product, its connection with TTL,

3) there is no possibility to take into account the specific place where the equipment is connected to aspiration, which makes it impossible to control the parameters of the air environment in the equipment.

The aim of the invention is to increase the efficiency of aspiration.

The method consists in the fact that prior to the beginning of the product delivery in the presence of stable

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Aerodynamic connections in the line measure the total pressure at the inlet and outlet of each piece of equipment and process connections, and then by summing the aforementioned values, determine the operating point of the transport and processing line and its parameters, and after supplying the product, determine the zone of the greatest excess pressure and, at if it exceeds the pressure at the operating point, the first is reduced by interrupting or establishing additional aerodynamic links in the line.

FIG. 1 shows an analogous diagram of the operation of the transport and processing line and its method of aspiration; FIG. 2 - analogue circuit, divided into two nodes; in fig. 3 - simplified analog model; in fig. 4-characteristics of the equipment.

The method of aspiration of shelters is carried out as follows.

1. The steady-state aerodynamic coupling is determined by the static pressure method.

2. The aerodynamic characteristics of the equipment and its connections are measured by the full pressure method before the product is introduced into and out of the product.

3. Determine the tightness of the equipment.

4. According to the measurement results, the aerodynamic state of the system and each individual equipment is determined by the operating point of the system.

5. At the places of the highest overpressure, aerodynamic connections are established.

6. It is due to the suction extraction of vacuum air in the system so that the air velocity through the leaks is greater than or equal to the soaring speed of the dust.

To control the parameters of the dust-air environment in this system, it is necessary to know its state. For this purpose, an analog aerodynamic coupling scheme (Fig. 5a) is created in the form of equipment operation, as sources of energy transfer to air or resistance to air movement, and to cover them as air ducts. In the analog circuit, chain conveyor 1 is represented as resistance 1, drift 2 as fan 2, machine 3 shelter as resistance 3, and its tightness through resistance 4, gravity 5 through fan 5, capacity 6 through resistance 6. To solve this the schemes simplify it by breaking into two nodes A and B and constitute a simplified analog model (Fig. 56) of the aerodynamic connection of the air flow, on which node A is represented as a fan 1, node B by a fan 2, and the tightness of the machine 3

through resistance 3. To coordinate the operation of nodes A and B, they determine the state of the systems separately, and then find their overall state. For this, the operating points and characteristics of each of the systems are determined, after which they are combined and a common operating point of the system is obtained, which makes it possible to determine the aerodynamic parameters at any point of the system. The construction begins with a characteristic

5 resistance of the chain conveyor 1 - characteristic 1 and self-flow 2, the summation of these characteristics (sequential operation) receive the total characteristic of node A (curve 3). The next stage, the characteristics of node B, begin with the characteristic of the resistance of the container (curve 4) and its tightness (curve 5), compose them, obtain the general characteristic of their work (curve 6), apply self-leakage characteristic 5 (curve 7), fold it with general characteristic of capacitance (curve 6) and get the characteristic of the node B (curve 8). After that, the characteristic of node A (curve 3) is summarized with the machine leakage characteristic (curve 9), obtaining curve 10, since fan 1 is resistance to fan 2. At the intersection of curve 10 and curve 8, the working point of system A is obtained. Point A, using the method described above, makes it possible to determine the direction and speed of air, the tightness of the shelters, the pressure and flow rates of air at any point of the system. This makes it possible to purposefully change the parameters of the dusty environment in the transport and processing line, by means of air flow, changing the tightness of the equipment, changing the ejection of air in self-flows, by

5 changes in product speed, inclination angle, etc., aspiration connections to create a vacuum in the transport and processing line, at which the speed of air through the leakages is equal to or greater

0 speed of helix of a product that provides reliable elimination of dust emissions from equipment.

Claims (1)

Claims of Invention A method of aspiration of extensive shelters of a transport and processing line, including product flow, air suction from equipment and a change in the shelter of static pressure equipment by changing the pressure in the suction network, differing in that. what with In order to increase the efficiency, before the product starts to flow in the presence of stable aerodynamic connections in the line, the total pressure at the inlet and outlet of each equipment unit and the pressure loss due to the leakage of each equipment unit, as well as the total pressure at the inlet and outlet of technological connections are measured , the measurement results determine the value of the values characterizing the aerodynamic state of each one / H 0 The equipment and technological connections, and then, by summing the above values, determine the operating point of the transport and processing line and its parameters, and after supplying the product, determine the zone of the greatest overpressure and, if it exceeds the pressure value at the operating point, the first is reduced by interrupting or setting in the line of additional aerodynamic connections. ILG7 (b)