At present, many foreign stone mines, especially granite mines, have fully used diamond bead wire saws to mine block materials, and have also promoted multi-line diamond bead wire saws in sawing and processing granite block materials. However, many stone companies in China still use old-style frame saws. One of its significant advantages is the low cost of sawing, but there are many shortcomings ...
At present, there are still many stone mines in China that use the backward method of drilling and blasting to produce stone blocks. Not only is the production efficiency low and the operation is unsafe, especially because the rock mass is broken due to the explosion, the stone resources are seriously damaged and produced. The block size is irregular, and even scrapped due to cracks, the yield rate is very low.
Stone mining technology and equipment
At present, there are still many stone mines in China that use the backward method of drilling and blasting to produce stone blocks. Not only is the production efficiency low and the operation is unsafe, especially because the rock mass is broken due to the explosion, the stone resources are seriously damaged and produced. The block size is irregular, and even scrapped due to cracks, the yield rate is very low. It is estimated that only 5% to 8% of the mining volume can be processed into timber by drilling and blasting. In the early 1980s, some developed countries in the stone industry had explicitly banned the use of explosive blasting to mine stones, and replaced them with diamond bead wire saws and other advanced technologies. It can be said that this is a sign of the modernization of stone mining technology. An important indicator for measuring the modernization of mining technology in stone mines is: the number of cubic meters of mining waste per capita per day. Industry insiders of the International Department believe that China's stone mines have low productivity. The reason is the lack of mechanized equipment, backward mining technology, and poor production management. Some stone mines have an average annual mining volume of only a few hundred to several thousand cubic meters, and a few stone mines have an annual mining volume of more than 10,000 cubic meters, with an average annual output of 6m3. . The monthly per capita output is only 0.5m3, which is lower than that of India. As we all know, India is also a major stone producer. However, its granite mine is small in scale and has no modern equipment, so the productivity of stone blocks is very low. The daily average is only 1m3. Finland is the largest stone exporter among Scandinavian countries. Its granite mine production system is world-class. The annual export of granite is at least 250,000 tons. The mine production efficiency is as high as 40m3 per capita per day. The productivity of stone mines in South Africa is of a medium level, with a daily per capita of 8-10m3.
2. Stone processing machinery and equipment
In the past ten years, the development of China's stone machinery equipment has made great progress, and some of the stand-alone performance automation has reached the international advanced level. However, China has not yet produced high-end technical equipment. In terms of the automation level of the overall production line of stone enterprises, there is still a gap compared with foreign countries. Some production links still rely on human operations, which not only affects the production efficiency, but also has unstable factors for the quality of the finished products due to the low quality of employees. Even though most of the stone companies in Italy, the world's leading stone manufacturer, use highly automated production lines, they still need a certain amount of stone knowledge and experienced personnel to master the technological parameters of the processing process to produce top-level finished stone products.
At present, many foreign stone mines, especially granite mines, have fully used diamond bead wire saws to mine block materials, and have also promoted multi-line diamond bead wire saws in sawing and processing granite block materials. However, many stone companies in China still use old-style frame saws. One of its significant advantages is the low cost of sawing, but there are many disadvantages:
① The assembly cost is high, about four times of the diamond bead wire saw;
② There are many operators, and at least two people are required to operate. More people need to work together when changing the saw blade;
③Saw cutting speed is slow, the cutting speed of the old frame saw is only 2cm / h. The cutting speed of the new frame is only 3.5-3.8cm / h. And the cutting speed of the diamond bead wire saw is as high as 20cm / h, which may be increased to 30cm / h;
Influence of diamond saw blade on stone
④The surface of the plate cut by the frame saw is rough, and the flatness is also poor, so the polishing speed is low, 100cm / min, and the surface of the plate cut by the diamond bead rope saw is smooth, and the polishing speed can be as high as 160cm / min. Thus reducing grinding and polishing processing time;
⑤ Energy consumption and material consumption are relatively high;
⑥ Disposal of scrap steel mortar and dust at the work site cause serious environmental pollution.
3. The quality of the finished stone
People in the international stone industry believe that the quality of Chinese stone products is not high because the stone processing equipment and process used are lagging behind other countries. Take the production of granite facing bricks as an example. Granite blocks mined from mines are mostly irregular in shape and vary in size; sawing into granite plates generally uses diamond circular saw blades with a diameter of 1m and 1.6m. The quality of the saw blades is not high and is cut down. The plate is usually polished and polished by a rocker arm, and the processing is mostly a manual process operation, that is, a highly automated grinding and polishing machine is used, and the quality of the abrasive used in the matching grinding head is poor; the polished plate is sawn into a common cross-cutting machine A certain size, the degree of automation of the production process is low. In the 1990s, many European countries have adopted advanced sawing machines and high-quality saw blades. The production of granite facing bricks is almost fully automated. The latest generation of sawing machines are equipped with up to 80 diamond circular saw blades with a diameter of 1m. Due to the use of high-quality diamonds, the linear speed of the saw blade can be up to 35m / s, the feed speed is 17m / min, each blade The sawing rate is 1m2 / h. In contrast, sawing machines used in China are generally only equipped with 5 saw blades with a diameter of 1m or 1.6m, and the saw blade base and diamond are of poor quality, so the saw blade line The speed is limited to 17m / s or 27m / s, the feed rate is slow, the sawing rate of each saw blade is about /0.3m2/h at 5m / min.
This article is excerpted from: marble cutting machine Manufacturer Wanlong Group