Iokhelson Z. Explosion protection of mine electrical equipment with heating elements (scientific elaboration and development)

The thesis shows the pioneer solution of a scientific and technological problem in the field of explosion protection of mine electrical equipment and work safety in mines, which is important in the coal industry of Ukraine and consisting in providing work safety in coal mines when using mine electrical equipment with heating elements without explosionproof enclosures, sophistication and size/weight increase, with a possibility to produce this equipment with a special level of explosion protection. It is proposed to divide the variety of heating elements, which are used in mine electrical equipment and have different oxidation characteristics, into three groups: a) not oxidable (including practically not oxidable), b) slowly oxidable and blown, and c) fast oxidable and blown. On the basis of logic-mathematical and experimental methods taking into account the thermal the-ory of combustion and explosion, dependences are determined between safe temperatures of the elements in consideration and their dimensions, oxidation characteristic, mass transfer conditions, and also between intrinsic safety parameters of various electric circuits and temperatures of sparking electrodes. Influence of operational conditions of heating elements in mines on safe characteristics of these elements was analyzed and taken into account. Explosion protection of mine electrical equipment with heating elements is achieved without using explosionproof enclosures, by special means for any level of explosion protection of this equipment. Introducing the thesis results in the coal industry of Ukraine has led to social achievements in national economy. Key words: heating elements, mine electrical equipment, explosion protection, surface temperature, electric sparks, operational conditions, special kind of protection, social achievements in national economy.