Design Requirements for Explosion Proof Tablet compute

Design Requirements for Explosion-Proof Tablet compute

The complexity of the explosion-proof environment, it is difficult to analyze and judge its explosive hazard factors. To ensure the safety of the use of electrical appliances, it is necessary to strengthen the design of explosion-proof tablet PCs, and do a good job in the design selection and design and production of explosion-proof tablet PCs. Fundamentally optimize the explosion-proof tablet PC to make it more competitive in the market.

As the use of explosion-proof tablet PC environment has a certain explosive hazard, therefore, must use certain safety measures, so that explosion-proof tablet PC in addition to completing the electrical function of the ordinary electrical appliances, but also to detect and control the safety of the explosion hazardous area of electricity, communication and so on. In said common life in the type of explosion-proof tablet computer: intrinsically safe, explosion-proof, increased safety, etc., explosion-proof tablet computer is mainly divided into coal mine explosion-proof tablet computer and factory explosion-proof tablet computer two categories.

First, the general idea of explosion-proof electrical product design

(A) explosion-proof electrical equipment for the application of environmental requirements

① explosive hazardous operating environment with flammable and explosive vapors / gases. Explosive hazardous work environment with flammable dust.

② Hazardous working environment where combustible dust and flammable and explosive vapors/gases exist at the same time, such as solid coal product workshop and its weighing, coating, packaging, transportation and other devices. Moreover, with the continuous development of coal enterprises, hazardous operating environments will become more and more common, which requires coal enterprises to attach great importance to the use of explosion-proof tablet PC equipment in the production process. At the same time, the design part should also be further 1 research on explosion-proof tablet PC.

③ in the first three cases on the basis of other special conditions (such as corrosive media, low temperature, high temperature and high humidity, vibration, sand, dust, rain, etc.) must also be used in the environment of explosion-proof tablet PC products.

(B) explosion-proof tablet computer equipment selection

According to the different explosive hazards of the working environment in the enterprise, the steam / gas hazardous areas are divided into: 0 area, 1 area, 2 areas. The division is based on the degree of release of explosive hazards. Generally, Zone 0 is limited to areas with small vents or within coal installations. Explosion-proof tablet PCs are generally used in zones 1 and 2, especially in zone 2 with sand, dust, rain and corrosion, it is necessary to use explosion-proof tablet PC equipment with strong explosion-proof features.

In the workplace with explosive hazards, there are often salt spray, chemical corrosion and other factors, which not only make the mechanical function and electrical performance of the equipment and appliances are seriously damaged, but also the explosion-proof function of the equipment is seriously damaged. Therefore, in the selection of explosion-proof tablet PCs, it is necessary to determine its resistance and safety. In the flammable dust hazardous environment should be used to limit the surface temperature protection and shell protection structure, to avoid dust into the equipment shell, adsorption on the insulator, resulting in production accidents due to circuit short circuit.

For dust and flammable and explosive gases exist at the same time the dangerous workplace, the choice of equipment, be sure to choose double explosion-proof electrical equipment, its explosion-proof level in order to meet the characteristics of flammable and explosive gases, but also must meet the characteristics of flammable gases.

Second, explosion-proof electrical design and production requirements

(A) power supply design

Independent power supply batteries and dry batteries are intrinsically safe and easy to carry. Battery and dry cell are resistive circuit, the power supply of its power safety parameters can be determined according to the resistive minimum ignition current curve to achieve. Using the maximum voltage of the battery, find out the minimum ignition current, and then divided by the value of the safety factor, you can get the maximum safety current value allowed by the battery. The direct short circuit of the battery is the most serious discharge state of the battery, therefore, when carrying out the power supply design, the intrinsic safety performance of the power supply must be considered, and the maximum short circuit current is used as a measurement standard.

(B) Circuit design

When carrying out circuit design, the electrical function of the appliance must be fully considered so that the correctness of the electrical principle is guaranteed. Secondly, the insulation parameters, creepage distance and electrical gap of explosion-proof tablet PC must be consistent with the relevant requirements of GB3836.

(C) shell design

Shell design must have a strong anti-collision function, impact resistance and good internal quality, while the anti-static function and thermal conductivity must also have a certain degree of strength, but also must design a delicate and durable appearance of the shape.

① explosion-proof tablet PC shell on the basic requirements of the material: in the design of the shell, the shell of the explosion-proof tablet PC must have strong corrosion resistance, oxidation resistance, impact strength, shell surface without static electricity, high thermal conductivity, good processing performance. At present, some countries in the small explosion-proof tablet PC shell production are selected brass as the main material. Due to the serious lack of brass resources in our country, therefore, most of the engineering plastics, cast steel, cast iron, aluminum alloy and other materials used in our country to produce explosion-proof tablet PC shell. As our country on the chemical composition of industrial plastics, fire flower function, anti-static function puts forward higher requirements, so in the explosion-proof tablet PC shell production generally do not advocate the use of this kind of material. At the same time, cast steel, cast iron, there are easy to corrode characteristics, so the shell production is rarely used, China is now in favor of magnesium-free aluminum alloy and low magnesium aluminum alloy as a shell production material development direction.

② explosion-proof pad shell precision requirements: explosion-proof tablet PC shell with wiring nozzle, lead agencies, mounting devices, hanging devices, explosion-proof bonding surface and iconic characters, etc., the shape of its form is generally more complex. Therefore, the shell of the production process has a strong precision, so that the characters and other content can be clearly shown.

③ castings of the inherent requirements: according to relevant regulations, in the shell processing is completed, must be carried out hydraulic testing, hydraulic test pressure should be measured for the explosion pressure of 1.5 times, but at least 0.35MPa. Pressure to maintain 10 + 2s, “to discontinuous dripping (every interval of more than 10s dripping 1 drop for discontinuous dripping) for qualified” provisions for Judgment. And in the test pressure and the specified time, the shell under test without structural damage or permanent deformation that may affect the performance of explosion-proof. In addition, explosion-proof shell processing is completed, its surface can not appear pinhole, air holes, etc., the casting must be organized uniformly, with good densification, surface finish.

④ practicality and economic requirements: in the design of the shell, but also must take into account its practicality and economy, in the production of explosion-proof tablet PC shell must have low energy consumption, less consumables, light weight, small size and so on, and thus reduce production costs and improve economic efficiency.

In short, explosion-proof tablet computer is an important factor in the production of coal enterprises to be carried out smoothly, therefore, we must strengthen the design of     explosion-proof tablet computer, and further improve the design theory of explosion-proof tablet computer, so that the explosion-proof performance of explosion-proof tablet computer has been further improved, the safety performance and reliability of the operation has been improved, and then promote the development of China’s coal enterprises.