This method generally does not divide the mine room and the pillars, and one step is to recover. Its characteristics are: stratified mining from bottom to top, each layer of mining is to divide the roadway into the stratified full height (or vertical direction) after the stratified contact road, and carry out the road mining at intervals. After the first batch of roads is completed, the roof is filled immediately, and then another batch of roads is taken back and filled. After the recovery and filling work of the entire layer is completed, the road is used to pick up the upper layer.
In order to reduce the exposed area of ​​the roof and improve the safety of the mining work, the ore is not stable or the ore is not stable, and the ore is not stable. The main advantages of the upward approach filling mining method are safe recovery, high ore recovery rate and low depletion rate. However, the mining method has lower mining intensity and labor productivity, and has higher requirements for filling and topping.
•Metal
Floor Fan 220V~50Hz, 60 W
•3
Speeds Push Button
•DC Copper Motor or AC Aluminum
Motor
•Metal
Body, Grill Cover and Grill
•3 Aluminum
Blades
•Power
cord:
3 x
0.75mm2 x 1.5m (Useful Length),
•VDE
Cable and VDE Two Round Pin Plug,
•Chrome
/ Spray Color
DC Air Circulation Stand Fan
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