Today, explosive industries are not only enterprises and objects of the chemical, mining, oil and gas, and nuclear industries. Explosive and fire-hazardous enterprises include, for example, food production enterprises: flour mills, confectionery, wine and vodka; as well as woodworking and pulp and paper mills, cement and iron-concrete plants, etc. d. In addition, a modern enterprise of any industry has explosive zones in its structure, t. to. at any modern production there are warehouses of fuels and lubricants and paint products, areas of electroplating and high-temperature processing, paint shops or chambers, etc. p. Explosion protection - measures that ensure the explosion safety of equipment for operation in explosive environments, the processes of its production, operation, storage, transportation, sale and disposal.
Technical solutions include the use of equipment (primarily electrical equipment) that is not capable of causing an explosion. This is achieved, for example, by using equipment in . com/catalog/cat/00-00006583_%D0%92%D0%B7%D1%80%D1%8B%D0%B2%D0%BE%D0%B7%D0%B0%D1%89%D0%B8%D1%89%D0%B5%D0%BD%D0%BD%D1%8B%D0%B5_%D0%BA%D0%BE%D1%80%D0%BF%D1%83%D1%81%D0%B0">housing that can withstand the pressure of the explosion , in conjunction with normalized size of the gaps between the connecting flanges or filled with environments in which the occurrence of the explosion is impossible (oil sand), under a high internal pressure, which cannot penetrate the external explosive atmosphere. Also, the main measures of explosion protection include the use of . se-import. com/catalog/cat/00-00006585_%D0%9A%D0%BE%D1%80%D0%BF%D1%83%D1%81%D0%B0%20%D1%81%D0%BE%20%D0%B2%D0%B7%D1%80%D1%8B%D0%B2%D0%BE%D0%BD%D0%B5%D0%BF%D1%80%D0%BE%D0%BD%D0%B8%D1%86%D0%B0%D0%B5%D0%BC%D0%BE%D0%B9%20%D0%BE%D0%B1%D0%BE%D0%BB%D0%BE%D1%87%D0%BA%D0%BE%D0%B9" target="_blank">взрывонепроницаемых оболочек. In this case, the electrical equipment is placed in a strong shell that can withstand an internal explosion without deforming the housing. Protection is provided by the gaps of the housing elements, which ensure the release of gases formed during the flash into the external atmosphere without undermining the surrounding explosive environment. All electrical inputs are carefully sealed at the points of insertion into the shell. The main application of explosion-proof shells - . se-import. com/catalog/cat/00-00006585_%D0%9A%D0%BE%D1%80%D0%BF%D1%83%D1%81%D0%B0%20%D1%81%D0%BE%20%D0%B2%D0%B7%D1%80%D1%8B%D0%B2%D0%BE%D0%BD%D0%B5%D0%BF%D1%80%D0%BE%D0%BD%D0%B8%D1%86%D0%B0%D0%B5%D0%BC%D0%BE%D0%B9%20%D0%BE%D0%B1%D0%BE%D0%BB%D0%BE%D1%87%D0%BA%D0%BE%D0%B9" target="_blank">клеммные и соединительные коробки, коммутирующие приборы, светильники, . se-import. com/catalog/cat/00-00006585_%D0%9A%D0%BE%D1%80%D0%BF%D1%83%D1%81%D0%B0%20%D1%81%D0%BE%20%D0%B2%D0%B7%D1%80%D1%8B%D0%B2%D0%BE%D0%BD%D0%B5%D0%BF%D1%80%D0%BE%D0%BD%D0%B8%D1%86%D0%B0%D0%B5%D0%BC%D0%BE%D0%B9%20%D0%BE%D0%B1%D0%BE%D0%BB%D0%BE%D1%87%D0%BA%D0%BE%D0%B9" target="_blank">control stations, switchgear, starters, electric motors, heating elements, . se-import. com/catalog/cat/00-00006585_%D0%9A%D0%BE%D1%80%D0%BF%D1%83%D1%81%D0%B0%20%D1%81%D0%BE%20%D0%B2%D0%B7%D1%80%D1%8B%D0%B2%D0%BE%D0%BD%D0%B5%D0%BF%D1%80%D0%BE%D0%BD%D0%B8%D1%86%D0%B0%D0%B5%D0%BC%D0%BE%D0%B9%20%D0%BE%D0%B1%D0%BE%D0%BB%D0%BE%D1%87%D0%BA%D0%BE%D0%B9" target="_blank">шкафы управления и др.
Classification of explosive zones
The risk of explosion occurs when the following sources are simultaneously present:
1. of air
2. combustible dust / combustible gases
3. active ignition sources
An explosive atmosphere can occur when combustible dust, flammable gases or vapors combine with air. There must also be an active ignition source capable of igniting this atmosphere. In the kachesva of such sources are:
. se-import. com/documents/tinyimages/27a24dde02ee4589a15917dcaece1387. jpg" rel="lightbox">The class of the explosive zone, according to which the choice of electrical equipment is made, is determined by technologists together with specialists of the design or operating organization. Regulatory documents contain a definition of the geometric dimensions of each class of zones.
Classification by gas:
| Zone 0 | Zone 1 | Zone 2 |
|
An area in which an explosive gas mixture is present constantly or for long periods of time A space in which an explosive environment is present for more than 1000 hours / year. |
An area in which there is a possibility of the presence of an explosive gas mixture under normal operating conditions A space in which an explosive environment is present from 10 to 1000 hours / year. |
An area in which the presence of an explosive gas mixture is unlikely under normal operating conditions, and if it occurs, it is rare, and exists for a very short time A space in which an explosive environment is present up to 10 hours / year. |
Classification by dust:
The modern classification of zones for gases and vapors includes zones of three classes: 0, 1 and 2, but practice has shown that the general classification of zones for gas and dust at the same time is unacceptable. Unlike areas for gas or steam, areas that are dangerous for the ignition of combustible dust cannot be classified depending on normal or emergency conditions and on the time. Increased ventilation can lead to the appearance of dust clouds and therefore increase, rather than reduce, the danger.
| Zone 20 | Zone 21 | Zone 22 |
|
An area in which combustible dust in the form of a cloud is constantly or partially present during normal operation of the equipment in an amount capable of producing a concentration sufficient for the explosion of combustible or flammable dust in mixtures with air, and/or where dust layers of arbitrary or excessive thickness can form. |
A zone not classified as a Class 20 zone in which combustible dust in the form of a cloud cannot be present during the normal operation of the equipment in an amount capable of producing a concentration sufficient for the explosion of combustible dust in mixtures with air. |
A zone not classified as zone 21, in which clouds of combustible dust can occur rarely and persist only for a short period, or in which the accumulation of layers of combustible dust can occur during abnormal operation, which can lead to the appearance of flammable dust mixtures in the air. If, based on abnormal conditions, the elimination of accumulations or dust layers cannot be guaranteed, then the zone is classified as a Class 21 zone. |
Equipment intended for operation within a zone of a particular class must have an appropriate level of explosion protection.
Example of GOST R marking:
1ExdIIAT3, where
| 1 | Ex | d | IIA | T3 |
| Explosion protection level sign | A sign of compliance with the standards | Sign of the type of explosion protection | Subgroup sign (mixture category) |
The sign of the temperature class (mixture group) |
Types and principle of explosion protection
| Type and principle of explosion protection | Schematic representation | Main application | Standard | |||
|
Explosion-proof shell The spread of the explosion to the external environment is excluded |
Ex d | . se-import. com/documents/tinyimages/fcac5de230cb490b30dd32adb88855ea. gif" alt="66" width="100" height="53" /> | Terminal and connection boxes, switching devices, lamps, control posts, switchgear, starters, electric motors, heating elements, control cabinets, IT equipment Zone 1, Zone 2 |
GOST R 51330. 1-99 (IEC 60079-1-98) |
||
| The equipment is designed for the explosion hazard category of the mixture I for work in mines and mines where there is a risk of explosion of mine methane and mixture II for work in conditions of possible formation of industrial explosive mixtures of gases and dust (according to the latest classification, category III is for dust) Equipment for the explosion hazard category of mixture II is divided into three subcategories of category II: IIA, IIB, IIC |
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Protection of the type e Exclusion of sparks or elevated temperature |
Ex e | . se-import. com/documents/tinyimages/8cb35f1335f82934bdd90c3f016c1a1f. gif" alt="67" width="100" height="53" /> | Terminal and connection boxes, lamps, control posts, switchgear, heating elements Zone 1 (partially), Zone 2 |
GOST R 51330. 8-99 | ||
|
Intrinsically safe electrical circuit Limiting the energy of a spark or an elevated temperature |
Ex i | . se-import. com/documents/tinyimages/39abbaa0a430240149574637da857809. gif" alt="68" width="100" height="53" /> | Measuring and regulating equipment, communication equipment, sensors, drives, battery lights | GOST R 51330. 10-99 (IEC 60079-11-99) |
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| Explosion protection levels of Exi -- electrical equipment | ||||||
| Explosive zone | 0 | 1 | 2 | |||
| ia | ia,ib | ia,ib,ic | ||||
| The equipment is designed for the explosion hazard category of the mixture I for work in mines and mines where there is a risk of explosion of mine methane and mixture II for work in conditions of possible formation of industrial explosive mixtures of gases and dust (according to the latest classification, category III is for dust) Equipment labeled ia, ib, ic for the explosion hazard category II mixtures are divided into three subcategories of category II: IIA, IIB, IIC |
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|
Filling or purging Ex-atmosphere is isolated from the source of ignition |
Ex p | . se-import. com/documents/tinyimages/8917a398a7c2f713e262ffbace83869e. gif" alt="69" width="100" height="53" /> | High-current switchboards, highly integrated IT equipment, analyzer devices, heavy-duty electric motors Zone 1, Zone 2 |
GOST R 51330. 3-99 | ||
|
Sealing with a compound Ex-atmosphere is isolated from the source of ignition |
Ex m | . se-import. com/documents/tinyimages/afd0e98bf0ecf31ab512c1d1ca155489. gif" alt="70" width="100" height="53" /> | Low-power switching devices, indicators, sensors Zone 1, Zone 2 |
GOST R 51330. 17-99 (IEC 60079-18-92) |
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|
Oil filling of the shell Ex-atmosphere is isolated from the source of ignition |
Ex o | . se-import. com/documents/tinyimages/f1fe1c2c699f4d55ff1a565dccdb5c2b. gif" alt="71" width="100" height="53" /> | Transformers, starting resistances Zone 2 |
GOST R 51330. 7-99 (IEC 60079-6-95) |
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|
Filling the shell with powder The spread of the explosion to the external environment is excluded |
Ex q | . se-import. com/documents/tinyimages/fef4ef30863e8e1474b6aee1f65338c0. gif" alt="72" width="100" height="53" /> | Transformers, capacitors, indicators Zone 1, Zone 2 |
GOST R 51330. 6-99 (IEC 60079-5-97) |
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|
Type of protection n They do not have an incendiary ability |
Ex n | . se-import. com/documents/tinyimages/a4a261d963cd297bb6fb2d9e6e4cb450. gif" alt="73" width="100" height="53" /> | All devices for Zone 2 | GOST R 51330. 14-99 | ||
|
Exn equipment is divided into five types:
|
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| The equipment is designed for the explosion hazard category of the mixture II for operation in conditions of possible formation of industrial explosive mixtures of gases and dust (according to the latest classification, category III is for dust) Equipment marked with pS or nL is divided into three subcategories of category II: IIA, IIB, IIC |
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Special protection reducing the probability of an electric spark |
Ex s | This type of explosion protection can be provided by the following means: the conclusion of electrical circuits in a sealed shell with a degree of protection IP67; sealing of electrical equipment with a material having insulating properties (compounds, sealants); exposure to an explosive mixture with devices and substances to absorb or reduce the concentration of the latter; and other methods. | All devices for Zone 1 and Zone 2 | GOST R 51330. 0-99 (IEC 60079-0-98) |
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The company "Sibelektronimport" is engaged in the supply of various. se-import. com/catalog/cat/00-00005715_%D0%92%D0%B7%D1%80%D1%8B%D0%B2%D0%BE%D0%B7%D0%B0%D1%89%D0%B8%D1%89%D1%91%D0%BD%D0%BD%D0%BE%D0%B5%20%D0%BE%D0%B1%D0%BE%D1%80%D1%83%D0%B4%D0%BE%D0%B2%D0%B0%D0%BD%D0%B8%D0%B5" target="_blank">explosion-proof equipment. We can also supply any necessary equipment that is not included in our catalog to order.
Source: http://www. rose-rf. ru