We started making this kind of manual lathe machine since 1955 as one of a leading state-owned companies, which is used for metal cutting or processing as traditional ways, and of great quality upon on more than 66 years experience.
It is with precision ground and hardened bed ways,and removable gap is provided for bigger diameter of workpiece.
Different specification or requirements could be customized based on demands.
Center Lathe, Centre Lathe, Machine Tool, Lathe Machine, lathe machining Yuxi JianFu Group Machine Tool Co., Ltd. , https://www.yucymachine.com
1) Basically similar to the bottom-column caving method. But there are also differences. For the no-column caving method, the caving mine is not released from the end of the mining roadway, thus the development of the ellipsoid, loose ellipsoid and waste rock funnel is incomplete (it is affected by the vertical mining face) The ellipsoid is slightly more than half of the six. Moreover, the axis is skewed and forms a small angle with the mine wall. On the section perpendicular to the mining roadway, there is no change in the shape of the ellipsoid. (Axis deflection angle can be 4 °)
1 On the ore wall, (90°), in addition to cutting the ellipsoid outside the body, the long axis of the ellipsoid is slightly inclined forward and obliquely intersects the ore wall to form a small angle.
2 The ore wall is inclined forward, and the ellipsoid is cut by the ore wall and is inclined forward.
3 The mine wall is inclined backwards. The ellipsoid is reduced by the cut portion. Loosening the ellipsoid and releasing the waste rock funnel also change accordingly.
4 On the section of the vertical mining roadway, the shape of the ellipsoid is released, and there is no change.
[Reference] The reason why the axis is skewed is that the inner friction angle of the ore is smaller than the outer friction angle, and the place where the resistance is large, the ore movement speed is slow.
2) There is a ridge loss between two adjacent mining roadways.
Between the two recovery routes, the loss of ore present is called ridge loss. The ore lost in the ridge can be recovered when the next section is harvested.
However, if the recovery approach (upper and lower sections) is not in a diamond arrangement, the ridge loss is difficult to recover.
3) About positive loss
On the front side of the mining roadway, because the thickness of the collapsed ore layer is greater than the depth of the excavation equipment, and the ore that has left a diagonal strip after the mine is discharged, we call these losses a positive loss.
The ore that is lost in the front is difficult to recycle because the ore lost in the front is mixed together in the next section. If you can recycle a part, it is also a depleted ore.
[Note]: The ore lost in the front and the ore lost in the ridge are actually integrated.
November 13, 2021