Block

BLOCK (EN: block; DE: Block, Vollstein; FR: block; ES: bloque; RU: блок) -

1) In case of the underground development of the coal deposits is the part of the mine field, which is unsealed from the surface and is ventilated independently. They use the division into the blocks in case of the high gas content of the mine fields, with the size along the strike of more than 6-8 kilometres, for the improvement of their ventilation, in case of the necessity for ensuring the economic effectiveness of construction and operation of the large mines. For the transportation of the coal to the main shafts at each horizon, they connect the blocks with the shafts by the trunk drifts. The sizes of the blocks along the strike are 2.5-5 kilometres, while along the dip and across the strike are equal to the sizes of the mine field. They also understand as block the fields of several mines, which are connected by the underground mine workings, are independently ventilated, and are united into the single mining enterprise.

2) In case of the underground development of the ore deposits is the excavation place within the limits of the level with the usage of the single system of development; the height of the block is equal to the height of the level, the width is equal to the thickness of the ore deposition or of the part of it (during the development of the especially thick depositions).

3) In case of the open pit development of the deposits is the part of the bench, which is being developed by the independent means of breaking or excavation.

They distinguish the blocks for excavator, namely, the part of the bench (along the length), which is purposed for the excavation by the single excavator; the minimal length in case of the railway transport is 250-300 metres, in case of the automotive transport is 50-150 metres. The quantity of the blocks on the single working horizon in case of the railway transport is at most 3, in case of the automotive transport is at most 5-6. In case of the development of the deposits, which are containing different grades of the ores, and of the deposits with the complicated embedment, they perform the division into the blocks with taking into account the ensuring of the homogeneity of the rock mass, which is being obtained; the length of the blocks in this case may be unequal. In case of the development of the hard rocks, they divide each block into three parts, within one of which they perform the loading of the rock mass, within the second one they perform the preparation of the massif to blasting (the so called "Blasting block"), and within the third one they perform the drilling of the blasting boreholes. The volume of the rock mass within the block must ensure the uninterrupted work of the loading equipment during at least 2-3 days.