With the gradual emergence of the advantages of mechanized construction, more and more industries pursue higher efficiency and safer operation, which puts forward higher requirements for the industrial equipment production industry. Underground operation is also gradually developing towards mechanization, and the types of mechanical equipment matching it are gradually increasing, which plays a very important role in improving underground work efficiency.

井下装载机的应用环境特殊，不仅对其机械结构组件有大大的挑战性，在电缆敷设上更有着多重考量。为使卷筒与电动机间的电缆在卷筒转动过程中不出现相对运动，在卷筒内设计了电刷和滑环，这一装置在一定情况下可能产生火花，当空气中含有一定浓度的瓦斯时，就会燃烧或爆炸，所以卷筒要具有耐爆性和不传爆性。

The application environment of underground loader is special, which not only challenges its mechanical structure components, but also has multiple considerations in cable laying. In order to prevent the cable between the drum and the motor from relative movement during the rotation of the drum, brushes and slip rings are designed in the drum. This device may produce sparks under certain circumstances. When the air contains a certain concentration of gas, it will burn or explode. Therefore, the drum must have explosion resistance and non explosion transmission.

耐爆性是指卷筒外壳的强度，当卷筒内部发生爆炸时，应使其不发生变形和损坏，不致使爆炸火焰直接点燃矿井中的瓦斯混合物，从而达到耐爆要求，它是由外壳的材质和机械结构强度来保证的。

Explosion resistance refers to the strength of the drum shell. In case of explosion inside the drum, it shall not be deformed and damaged, so as not to cause the explosion flame to directly ignite the gas mixture in the mine, so as to meet the explosion resistance requirements. It is guaranteed by the material and mechanical structure strength of the shell.

根据材料力学及实验结果，对于钢板外壳，理论上厚度为3～4mm，铸铁为6mm。不传爆性是指甲烷与空气混合物在内部爆炸时，火花不会传到壳体外部，因而也就不会引起壳外可燃气体的爆炸，这一点可通过外壳装配接合面的宽度L、临界间隙dkp和加工表面精度来保证。

According to the material mechanics and experimental results, the theoretical thickness of steel plate shell is 3 ~ 4mm and cast iron is 6mm. Non explosive property means that when the mixture of methane and air explodes inside, the spark will not be transmitted to the outside of the shell, so it will not cause the explosion of combustible gas outside the shell. This can be ensured by the width l of the shell assembly joint surface, the critical gap DKP and the machining surface accuracy.