The shaft is arranged outside the moving belt of the ore body (the section has a specified safety distance), and the stone door is made to communicate with the ore body. The applicable conditions for this development plan are: (1) From a technical point of view, it is impossible to dig a shaft in the lower part of the ore body (the following rock layer is watery or broken, and there are other permanent buildings on the surface). (2) The development of the upper plate is more economically reasonable than the development of the lower plate (the lower part of the deposit is a mountain, there is no industrial site, the ground transportation is difficult and the cost is high), as shown in the terrain conditions shown in Figure 7-6. It is more suitable.
Compared with the development of the lower shaft, the upper shaft has obvious disadvantages: the upper middle section has a long stone gate, the initial base amount is large, the infrastructure construction time is long, and the initial infrastructure investment must also increase. In view of the shortcomings of the on-board shaft scheme itself, this development scheme is generally not adopted.