The raw material of those Roll Forming Machine are cold rolled steel (low carbon steel plate) coil or plate, Roll forming machine just uses different roll forming processions and technical(according to actual panel profile), then make the flat sheet plate to be changed different corrugation plate. This name is a general name of cold rolled metal sheet machining machines, it has a widely contents. It covers all construction equipment and sheet metal machines, which the material are in cold rolled steel sheet range.
It includes these roll forming machines:
Roofing Machine
1. Tile Machine
2. Corrugated Sheet Machine
3.Floor Deck Roll Forming Machine
4.Wall Panel Roll Forming Machine
5.Purline roll forming machine
6.Guardrail Roll Forming Machine
7. Cable Tray Machine
8. Door and Window Frame Machine
9. Ridge Cap Roll Forming Machine
10. Metal Stud Machine
11.Double Layer Roll Forming Machine
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Figure 1 Gravity mining
1-Transportation roadway; 2-minening chute; 3-branch chute; 4-grid roadway;
5-funnel; 6-pull roadway; 7-pull hole; 8-way
6-Lotto hole; 7-mining chute; 8-transport roadway; 9-return airway roadway; 10-return roadway
Phase-down method for natural caving mining
The bottoming method has two methods: shallow hole bottoming and deep hole bottoming (see Figures 1, 2). The bottoming roadway is generally arranged at a level of 4 to 15 m above the level of the mined mine, and the parallel parallel bottoming roadway with the same spacing between the tunneling and the funnel. The distance between the level of the mined and the level of the bottom is mainly determined by the stability of the rock and the method of pulling the bottom.
Figure 2 Scraper tapping system
1-Scraper road; 2-loading approach; 3-flat bottom V-groove; 4-draw roadway; 5--mining trench blasthole;
The lowest height of the bottom is that after the bottom is pulled, the spine between the funnels does not hinder the natural collapse of the upper ore. That is, there is no support point at the bottom level. The height of the shallow hole bottom is 2.5 to 5.0 m. When using a deep hole (or a medium-deep hole) to pull the bottom, it is required to form a bottoming space with a height of more than 3.0 m above the funnel spine after pulling down.
The bottoming speed is adapted to the speed of the caving and the output. In the initial stage, the bottom should not be too fast, so that the secondary stress can be fully developed and it is favorable to collapse, but it should not be too slow or paused. This is unfavorable for the mining roadway and should be maintained evenly. With the accumulation of production experience, the speed of pulling the bottom can be appropriately accelerated.
The blasting holes are blasted in sequence with the advancing line, and each row is blasted 2 to 3 rows (about 5 m). After each blasting, it is necessary to carefully check whether the residual column is left. Once the residual column is found, it must be treated in time. Otherwise, the ore will be prevented from collapsing naturally and stress concentration will occur on the mining roadway.
The bottom is generally pushed from the side close to the collapsed ore block, or from the upper plate of the ore body, and is stepped along the diagonal direction. It is necessary to strictly control the advance distance of the adjacent pull-up, generally within 15m. When the uneven distribution of ore grade in order to recover funds early, typically the initial undercut of high grade ore selected segment. From the point of view of rock mechanics, it is necessary to start the bottoming from the weak ore section, which is conducive to the ore caving, and is also beneficial to the maintenance of the mining roadway. When a large structural fault passes through the mining section, the bottom line must be pushed vertically. It should be noted that the direction of the bottom pusher line is as close as possible to the horizontal principal stress direction of the original rock. The shape of the horizontal area of ​​the bottom is preferably rectangular, and the long side of the rectangle is perpendicular to the horizontal principal stress direction of the original rock, which is beneficial to the collapse of the ore body. . The bottom push line cannot be parallel with the lower mine roadway, so that the arch stress can be applied to a certain roadway in the same period.