The cutting patio blasting uses 2# rock emulsion explosive (Table 2) and a plastic detonating tube detonation network. The detonating tube shall be connected reliably, the detonating tube detonator shall be initiating the detonating tube, and the emulsion excavation shall be used for the tunnel excavation. The specification is 32mm×200m, the mass is (200±10)g; the detonator adopts the detonating tube detonator, and the non-electric tube detonates. The way, the detonator model is MFB-200. The type of plastic detonating tube is 8# detonator, which is a non-conducting squib, which is divided into instant detonating tube detonator and deferred detonating tube detonator. The length of detonating tube is 30m, and the detonation speed is 1950±50m/s. 3 cutting patio tunneling construction technology Article source: "Modern Mining", 2017.3 Other Machines And Spare Parts Paper Core Machine,Paper Core Cutting Machine,Paper Tube Cutting Machine,Automatic Paper Core Cutting Machine JIALONG PACKAGING MACHINERY CO.,LTD , https://www.jlcartonmachine.com
1 mining structure parameters and main cutting projects
The section of the Huibaoling iron ore mine is filled along the strike, with a length of 60m and a height of 70m (middle height). The width of the mine is the thickness of the ore body (Fig. 1) [2]. The ore body is divided into 3 sections with a section height of 23.3m. The mining and cutting engineering includes segmented roadway, sectioned rock drilling roadway, mining road, cutting patio, cutting lane, and returning wind well. The section roadway is arranged outside the vein, and the section rock drilling roadway is drilled from the section roadway to the mine body through the auxiliary slope road. The cutting patio is arranged on the side of the cutting lane, and the section size is 2m×2m (length×width), and the specific position is determined according to the actual inclination of the ore body (Fig. 2).
2.1 Rock drilling equipment
The rock drilling equipment used in the section of the Huibaoling Iron Mine is filled with the mining method. The rock drilling equipment used for the cutting of the pit is the YT28 rock drilling machine . The rock drilling machine is suitable for drilling horizontally on hard or hard rock with a hardness of 8-18. , inclined and vertical blastholes, the diameter of the blasthole is generally 34 ~ 42mm, the effective economic drilling depth can reach 5m, the working wind pressure is 0.63MPa, the wind consumption is 3.3 ~ 4.9m3 / min, the rock drilling efficiency is 0. 2 ~ 0.25m / min. The main technical parameters of YT28 rock drill are shown in Table 1.
3.1 blasthole position determination
The Huibaoling iron ore construction team determined the peripheral hole and the auxiliary hole according to the center of the cutting patio placed on the site, and cut the center of the patio, that is, the position of the slotted hole. The six auxiliary air eyes were evenly arranged in a hexagonal shape at a distance of 7 cm from the slot hole. The adjacent auxiliary holes are evenly arranged in a square at a distance of 15 cm from the slot, and the four far auxiliary holes are evenly arranged in a square at a distance of 40 cm from the slot, and the eight peripheral holes are evenly arranged around the periphery of the patio, which can be blasted according to the previous shot. Appropriately increase or decrease the auxiliary holes. In principle, no less than 23 blastholes shall be constructed. The blasthole arrangement is shown in Figure 3.
3.2 Excavation and Charge Blasting
First, use 1m drill rod to dig, use a new drill bit, and dig into the tail of the shank, pull out the 1m drill rod, replace the 2m drill rod and continue to dig. The drill bit is the drill bit replaced by the previous 1m drill rod, and the same order is replaced by 2.5. 3m drill rod and drill bit are used for excavation. When the 3m drill rod is excavated, the single hole excavation work is basically completed. The single hole operation takes 12min, the effective excavation distance is about 2.8m, and the overall blasthole construction takes no less than 4. 8h. After all the drilling is completed, the charging blasting is carried out, and 14 to 15 2# rock emulsion explosives are installed in the boring hole and the auxiliary hole, and the entire blast hole is basically filled, and 11 to 14 2# rock emulsion explosives are installed in the peripheral hole, and the specific loading is carried out. The condition of the drug is determined based on the last blasting effect.
4 discussion
The 3B drill rod was used for the cutting of the Huibaoling iron ore cutting patio. The practice shows that the efficiency of the cutting patio is closely related to the geological structure within the construction area of ​​the mining area, and the mine with simple geological conditions within the construction scope The Platts hardness is large, the blasting effect and molding are good, and the blasting distance can reach 2.7~2.8m. However, for areas with complex geological structures and large faults and intercalated rocks, the efficiency of tunnel excavation is greatly affected. Firstly, the blasting effect in soft rock areas is extremely poor, and the adjacent blastholes are damaged by extrusion blasting. The minimum blasting distance Only about 1.8m; the complexity of the second geological conditions affects the normal excavation construction. The occurrence of faults and porphyries leads to obvious phenomenon of clamping and brazing, which reduces the efficiency of excavation. In addition, the timely follow-up of underground auxiliary facilities and the normality of wind pressure and water pressure used in construction are also related to the efficiency of cutting the cutting patio.
references
[1] Rao Yunzhang, Zhang Zhongya, Shu Taijing, et al. Settlement test of the full-tailed sand waste rock composite filling body in Huibaoling Iron Mine [J]. Metal mines, 2015 (11): 37-41.
[2] Song Baishu, Chen Renmin, Peng Jiabin, et al. Sa hot g of copper ore sublevel open stope filling subsequent structure parameter optimization [J]. Modern Mining, 2016(1): 8-12.
Author: Xu Wenbo; gold credit Mining Management Ltd. All Rights Reserved:
Digging Construction Technology of Huibaoling Iron Mine Cutting Patio to Improve Progressive Ruler
Bao Ling iron ore will be a great resource reserves, a large low-grade iron ore, the current control and inferred resources amounted to 1.7833 one hundred million t [1]. The average density of ore is 3.49t/m3, the average rock density is 2.7t/m3, the hardness of ore is 16~18, the Rockwell hardness coefficient is 12~16, the rock loosening coefficient is 1.6, and the rock resistion The strength is 68.1~122.1MPa. The distance between the two main ore belts at the top of the ore body is 200-280 m. The ore body is layered and layered, and the occurrence is consistent with the formation. The average total thickness of the ore body is 40.45m, the average grade of the deposit is TFe31.48%, and the MFe is 18.77%. According to the steep dip angle of the ore body, the thin to medium thickness of the ore body, the stability of the ore rock and the low grade of the ore, the design is based on the segmentation of the empty field, the filling method and the shallow hole retention ore filling method. For the segmented empty field and post-filling mining method, improving the driving efficiency of the cutting patio becomes the key to safe and efficient returning to the ore. Therefore, this study analyzes the excavation construction technology of the mine cutting patio to improve the cycle footage. 2 cutting patio construction rock drilling equipment and materials 2.2 Construction fire materials