Division of Main Explosion-Proof Electrical Appliances in Explosion-Proof Certification

With the rapid development of China's economic construction and the increasing scale of industrial production, the issue of explosion protection is even more important. In the petroleum, chemical, coal, and other industries, explosion-proof electrical products with various functions and various varieties are widely used. Explosion-proof electrical appliances can be stably and safely operated in various dangerous explosion environments during use, and relevant strict explosion-proof tests must be carried out before leaving the factory. The market demand for explosion-proof products is relatively large, so there are many manufacturers, mainly including small explosion-proof products such as lighting switches, transfer switches (combination switches), travel switches, and pull switches. These products mainly include explosion-proof ceiling fans, explosion-proof exhaust fans and explosion-proof axial fans. Their structure consists of explosion-proof motors, explosion-proof junction boxes and explosion-proof speed controllers and blades. Zhongnuo Testing has extensive product design and testing experience in the field of explosion protection. The following is an analysis of the twelve major categories of explosion-proof electrical products in the explosion-proof certification.

1．Explosion-Proof Control Box

It mainly includes a lighting distribution box for controlling the lighting system and a power box for controlling the power system. Most of these products are modular in construction and can control up to 12 circuits. The outer casing is mostly made of cast aluminum alloy, some of which are welded by steel plates, and a small part is made of insulating material. The interior is mainly composed of circuit breakers, contactors, thermal relays, transfer switches, signal lights, buttons and other components. The manufacturer can also choose according to the needs of users. The explosion-proof grade can reach up to IICT6. By the way, explosion-proof automatic switches, explosion-proof knife switches, and fuses are often used in some control applications to control the splitting of power or lighting distribution systems, but only become a single piece.

2. Explosion-Proof Starter Class

Such products include manual starters, electromagnetic starters, reversible electromagnetic starters, auto-decompression starters, Y-transform buck starters and feed switches. Explosion-proof starter products are used as terminal control equipment. Generally, a starter controls one motor, which belongs to a wide range of products. Its outer casing is usually made of cast aluminum alloy or steel. The interior is generally composed of contactors (air or vacuum), motor protection systems, signal lights, push buttons and autotransformers, and generally has local control, remote control and automatic control functions. Some products have circuit breakers as main switches to make the products more perfect.

3. Explosion-Proof Control Switch

The market demand for such products is relatively large, so there are many manufacturers, mainly including small explosion-proof products such as lighting switches, transfer switches (combination switches), travel switches, and pull switches. These products are available in explosion-proof grades up to IICT6. The explosion-proof housings are usually made of cast aluminum alloy die-cast composite structures, and a few manufacturers use other materials. These products are characterized by small size, internal components, low technical content, simple structure and easy fabrication.

4. Explosion-Proof Main Electrical Appliances

The main electric appliance is a switching electric appliance that is used to close or open the control circuit to issue commands or programs. This type of explosion-proof electrical appliances mainly includes control buttons and operating columns. The explosion-proof control button housing is usually made of polycarbonate, glass fiber reinforced unsaturated polyester resin or ABS plastic injection molding, and a small amount is die-casted from cast aluminum. The general structure is an increased safety type housing with built-in flameproof components, and can achieve anti-corrosion function, and the explosion-proof grade can reach IIC level. The operating column is mainly composed of a main box, a junction box and a pillar. The main box and the junction box are made in one piece, and some are made into separate bodies, each having its own characteristics. The material is basically made of cast aluminum alloy material. The interior consists of various instruments, switches, buttons and signal lights. Can be combined according to different needs. Example applications include Mine bracket lamp, mine flood light, mine LED roadway lamp, mine sound light signal device, mine floodlight, emergency light, metal halide lamp.

5. Explosion-Proof Junction Box

Electrical equipment must be connected to the power supply network via wires or cables to form a system to perform its functions. However, the connecting wires or cables cannot be infinitely long, and there are many places in the connection process that need to be connected in series and in parallel for wire tapping. This will inevitably cause the joint part to be exposed, which is likely to cause an accident. Explosion-proof junction box products are products that are produced to solve such problems, in order to further ensure safe production. These products include junction boxes, junction boxes, threading boxes, hanging boxes, junction boxes, etc. The outer casing is mainly made of cast aluminum alloy. A number of incoming and outgoing lead-in devices are provided as needed, and terminals are provided for connection or tapping. Most of these products are made of flameproof or increased safety type, the volume is large and small, the difference is large, and the explosion-proof grade can reach IIC level. Example applications include Mine bracket lamp, mine flood light, mine LED roadway lamp, mine sound light signal device, mine floodlight, emergency light, metal halide lamp.

6. Explosion-Proof Lamps

Lighting must be taken in any workplace and environment, and places containing a variety of explosive gases are no exception. Due to its many places of use, it is spread all over the production corners, which makes the explosion-proof lamps and lanterns products mass-produced. These products are available in many varieties and specifications, but can be roughly divided into lighting, signage, signal, and portable. From the light source types, they can be divided into incandescent lamps, mercury lamps, nano lamps, halogen lamps, and xenon lamps. And fluorescent lamps; from the structure is more numerous, generally hanging, hanging, wall-mounted, ceiling-mounted, portable, cantilever and so on. From the perspective of installation, explosion-proof lamps can be realized from 30 ° to 90 °. From power, it can range from tens of watts to hundreds of watts. The installation height starts from the ground to a few meters high. It can be said that explosion-proof lamps are the most productive and used products of all explosion-proof electrical products. Moreover, due to its specific function, it causes a large loss and a large replacement. The structure and shape of these products vary widely, but from the perspective of explosion-proof performance, it is basically explosion-proof type, and the shell material is mostly cast aluminum alloy, which can basically satisfy the users in the places below IIC. A need for lighting and display functions. Example applications include Mine bracket lamp, mine flood light, mine LED roadway lamp, mine sound and light signal device.

7. Explosion-Proof Connection

The main function of the explosion-proof connection is for cable connection and cable branching. Its main products are explosion-proof plugs and explosion-proof power outlet boxes. The rated voltage is 220V~380V, the rated working current is up to 100A. The variety has two poles, three poles plus neutral wire and grounding wire structure. The outer shell of the product is made of metal and plastic material, and the explosion-proof grade can reach IIC level. The inside is mainly composed of connectors, and some products are equipped with switches with breakpoints. This switch and the connector have a chain function, that is, the switch is first opened and then plugged, and the plug is inserted first. Products without switches also have to disconnect the ground wire after disconnecting the main circuit.

The function of inserting the main circuit after inserting the ground wire first. This is all done to ensure safe operation. Most of these products are used for direct operation, so their insulation performance requirements are generally high, and must not be ignored.

8. Explosion-Proof Fans

These products mainly include explosion-proof ceiling fans, explosion-proof exhaust fans and explosion-proof axial fans. Their structure consists of explosion-proof motors, explosion-proof junction boxes and explosion-proof speed controllers and blades. Its rated working voltage is generally up to 380V, and the explosion-proof grade can reach IIBT4.

9.Explosion-Proof Electrical Appliances with Heating Function

Petrochemical companies often need some heating equipment and electrical heating equipment in the production process, so the explosion-proof problem of such products is also very important. The main products are explosion-proof electric heaters and explosion-proof heaters. Since the main functions of explosion-proof control transformers and explosion-proof ballasts are not to obtain thermal energy, they also generate heat during operation and should be given great attention, so they are all included in such products. Of course, in today's rapid development of technology, there will also be many electric heating equipment made of high-tech materials, but the explosion-proof problem can not be ignored. The main components of explosion-proof heating equipment are components such as windings, controllers and junction boxes, and often have protection functions for temperature control or monitoring. These products are basically explosion-proof type, and the explosion-proof grade is IIBT4.

10. Explosion-Proof Alarm Electrical Appliances

In some production situations, some lights and sounds are often needed to remind people of the actions that are more important in environments with explosive hazardous gases. Its main products are explosion-proof indicator lights, explosion-proof electric bells, explosion-proof electric flutes, explosion-proof buzzers and other products. The structure is usually explosion-proof, made of cast aluminum alloy, and the explosion-proof grade can reach IICT6. Its working voltage can be divided into straight 36~220V and AC can reach 380V. Explosion-proof junction boxes and explosion-proof housings are the main structural components.

11. Explosion-Proof Electromagnets

These products mainly include explosion-proof electromagnets, explosion-proof solenoid valves, and explosion-proof electromagnetic drives. The working principle is that under the action of electromagnetic field, the electromagnetic force generated by the electromagnetic force is used to push the mechanical equipment to work, and is generally used for braking. Most of the structure is explosion-proof, made of cast steel or cast iron, and the explosion-proof grade is IIBT6. The main technical parameters are generally thrust or suction (calculated in kg) and current rate. It is not allowed to be energized for a long time, otherwise it is easy to overheat and cause danger.

12. Other Explosion-Proof

In the complex production process, many special requirements are often encountered, and special explosion-proof electrical products must be manufactured. Due to the low output of these products and the special requirements, they are non-standard products, so they are classified into other categories. There are mainly electrical instruments, temperature transmitters, pressure transmitters, speed transmitters, level gauges, quantitative controllers, ignition devices, cameras and other products. These products are basically manufactured according to the production needs. Although their performance requirements are different, most of them are made of metal, the type is explosion-proof or increased-safety structure, and a small number of products are intrinsically safe. Type products, their working voltage and working current are generally low, and the explosion-proof grade is IICT6. Mine bracket lamp, mine flood light, mine LED roadway lamp, mine sound light signal device, mine floodlight, emergency light, metal halide lamp.

The above-mentioned factory explosion-proof electrical products are roughly divided into twelve categories, in order to obtain a clearer rational understanding of these products. The above classification may be missing or incomplete. But basically it includes most of the products that are currently on the market. It should be pointed out that there are also some products, such as reducer joints, sealing joints, pipe joints, unions, flexible joints and other products. Many manufacturers also list them as explosion-proof products, which is a misconception. These products can only be called auxiliary parts of explosion-proof electrical products. Therefore, the product classification here does not include these products.