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1. Based on the characteristics, structure, and usage location of explosion-proof electrical products, combined with basic knowledge of explosion-proof and the provisions of explosion-proof standards, comprehensively analyze the explosion-proof type of product design. What kind of explosion-proof type is more suitable and economical. For example, explosion-proof flashlights belong to mobile electrical equipment. According to the location of Zone 0, they can only be made into intrinsic safety type IA, and the product needs to limit its energy, resulting in lower illumination. If used in Zone 1 locations, it can be made into explosion-proof type D or intrinsic safety type IA or IB. When high illumination is required, it is easy to achieve the goal by making it explosion-proof.

2. After determining the explosion-proof type, design the product structure according to the corresponding explosion-proof standards. If it is a flameproof type, it must comply with the relevant provisions of GB3836.1 and GB3836.2. Taking explosion-proof flashlights as an example: for those designed as explosion-proof, the material of the casing should be determined first. Plastic casings should comply with the provisions of Chapter 7 of GB3836.1, and casings containing light metals should comply with the provisions of Chapter 8 of GB3836.1. Should its structure be determined according to the provisions of GB3836.2 to choose a planar joint surface? Stop joint surface? Threaded joint surface or other joint surface? The lamp head and tail of explosion-proof flashlights are prone to use threaded joint surfaces, and the glass should be made of tempered glass that can withstand impacts of 4J energy.

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