Work in many industries such as chemical, oil, mining, metallurgy, requires using special equipment to provide extra protection from explosion and fires. Nowadays, the explosion and fire hazard location exists at all industrial enterprises, from the confectionery factory to the paint and varnish shop, without exception.
The term explosion-proof equipment means special equipment made in such a way that its operation minimizes the risk of ignition of the environment. Thus, the equipment itself cannot be a source of fire or explosion. Its design features include a special Ex (explosion-proof) component that prevents ignition. Thus, explosion-proof and flame-proof equipment is also called Ex-equipment.
An explosive zone is a limited space, where this equipment is used, divided into several explosion hazard classes:
- 0 — with the frequent appearance of explosive gases, vapors, and mixtures;
- 1 — similar to 0, but the appearance of explosive gases, mixtures of vapors appear from time to time (for example, accident);
- 2 — similar to 1, but in rare cases the occurrence of similar situations;
Depending on the zone, explosion protection equipment is selected.
Types of Ex Equipment
Explosion-proof equipment includes:
- Lighting Equipment;
- Control and Signaling cabinets;
- Connecting and Branching Boxes and Terminal Boxes;
- Rotary Switches and Control Stations;
- Light and Sound Signaling Station, Traffic Lights;
- Starters and Control Devices;
- Circuit Breaker;
- Electrical Connectors;
- Enclosures;
- Cable Glands;
- Fittings and Reducing Couplings;
Various types of explosion protection are used for these devices. The main principle is to isolate and seal the element of equipment to prevent the explosion from spreading beyond the envelope of the device.
Explosion-proof lighting
For lighting production, storage and fire-safe premises, gas stations, oil platforms, etc. use only lighting for explosive environments. Distinctive features of flame-proof lamps from general-purpose lighting devices are:
- a tight connection of parts;
- shell strength, ability to withstand a sharp increase in internal pressure;
- design providing a lower flashpoint of gases;
- thermal conditions in which the temperature of the external parts of the luminaires does not exceed the permissible value.
Explosion-proof Lighting Application area
Explosion-proof fixtures are mandatory for use in areas with increased explosion hazard:
- Industrial facilities.
- Oil-producing / refining enterprises.
- Coal mines and mines.
- Power plants (including nuclear).
- Chemical enterprises.
- Factories for the production of combustible substances.
- Warehouses for storage of paints and varnishes.
- Engineering enterprises.
- Boiler rooms.
- Gas station and other dangerous objects.
Explosion-proof luminaires are required for areas with increased explosion hazards. For example, as places of chemical, oil refining, and other industries, and gas stations, landfills, factories for the production of paints and varnishes or any combustible substances particularly stringent safety requirements are imposed, because of which, these companies are required to purchase specific equipment.
Explosion-proof Lighting Requirements
GOST R obliges the production of explosion-proof luminaires by the explosion protection standard Ex. All characteristics of the devices must be indicated on the marking:
Explosion Protection Group:
I – underground application for indoor and outdoor lighting of mines;
II – ground application, lighting devices for explosive objects, except for mines.
Classification types of protection:
m – filling compound;
d – flameproof enclosure;
e – increased protection;
Temperature class (from T1 to T6):
The temperature depends on the power of the lamp. The largest heating temperature of the surface of class T1 luminaires is 450 ° C, of class T6 - 100 ° C. That is, you need to choose such devices that do not heat up to the autoignition temperature of explosive mixtures.
T1 > 450℃;
T2 = 300-350℃;
T3 = 200-300℃;
T4 = 135-200℃;
T5 = 100-135℃;
T6 = 85-100℃;
Degree of protection against dust and moisture (IP):
Explosion-proof luminaires comply with IP65 and above. This means that the devices have reliable dust and moisture protection.
Benefits of using LED explosion-proof light fixtures
Today, hazardous objects are illuminated using LED, gas-discharge, and fluorescent lighting equipment. In recent years, most enterprises have used explosion-proof LED-lamps more actively, since they have many advantages. This is:
- Low power consumption. Explosion-proof LED lamps consume 70% less energy than traditional lamps.
- High energy efficiency. LED lighting devices are characterized by low energy consumption, reduce the load on transformers and power networks, are connected using cables of small cross-section.
- Durability. The guaranteed service life of LED explosion-proof lighting fixtures is 50,000 hours, the nominal - up to two times longer.
- Lack of operating costs. LEDs and drivers do not need to be replaced or repaired during their entire service life. Besides, the fixtures do not require special expensive disposal, as they do not have mercury and other harmful substances.
- Temperature range +/- 60 ° C. Devices can be used both in workshops of metallurgical plants and in the Far North, where there are many objects of the oil industry.
- High class of dust and moisture protection (IP65 / 66/67). Due to the complete tightness, the devices can be operated on the street and in rooms with high humidity and dust.
