柵原鉱山における下部鉱体の急速開発およびそれにともなう合理化

抄録

At the Yanahara Mine, systematic prospecting for the deeper district was started in 1951. In 1954 huge are deposit was discovered, It's are reserve is as much as seventeen million tons at present.
Those days, other are bodies were of ten suffered from spontaneous combustion and rock falls etc., and the mining condition was growing worse gradually. Under such a situation rapid developement of the new are body came to be the only way to prevent the decrease of production and rise of mining cost.
The developing construction contains many works such as Kabu-shaft sinking, Kabu-skip-shaft sinking, Central shaft sinking, application of new mining method, establishment of new ventilation system, reinforcement of drainage, modification of transportation system for filling materials, reinforcement of man and material shaft etc. They were devided into two periods as follows, that were performed steadily and positively.
1. Prospecting and developing period
2. Mining preparation and the construction to isolate the new deposit from others.
Among them, sinking of Central shaft.was started on 29 th April 1959, and was accomplished on 3rd March next year. During this period, 483m of sinking and 147m of level-driving were performed, and so 63m of average driving speed per month was obtained as the result, and that, no accident happened through all the time.
As regards mining method, combination of overhand stoping and sub-level stoping was arranged into new type in order to obtain perfect safety, high mechanization, and intensive mining.
As the collective effect, the attitude of monthly production of 40, 000 tons from new are body wasestablished within three yeors after the discovery. Further more, in 1960 monthly production of 100, 000 tons came to be possible from whole mine.
During those days, production from new deposit increased ten times as much, and at the same time whole mine production and its' mining cost could be maintained in normal situatior.
At present, considerable amount of production-increase is possible, and we have further got the clear indication of the newer are deposit by dint of those successful constructions.