Laser welding technology on a large diameter diamond saw blade
Natural granite rugged, beautiful, rich in resources, has been widely used in various types of construction, it has become one of the most basic civil interior and exterior decoration materials. Early 21st century, China's stone production, domestic consumption of stone, granite blocks and finished products for export are ranked first in the world for eight consecutive years and become the building materials industry export volume of individual products. However, the development of China's stone industry has been affected by related equipment, diamond tool manufacturing constraints, particularly for large format granite blocks cut diamond saw. With blade diameter increases, the cutting speed of conventional welding processes, whether in production or efficiency, are many deficiencies in the weld quality. This study reveals the practical application of laser welding technology in the welding of large diameter diamond saw, for enterprises to further improve the cost-effective tool provided.
Second, large-format granite cutting technology and tools and trends
Granite sheet production process mainly large-format frame strip (including sand) saws, diamond saw blades and diamond wire saw three ways. At present the quality and efficiency of domestic processing of high-quality large granite blocks are present more prominent issue.
Frame saws include diamond saws and sand saw two series, saw the traditional sand due to low processing efficiency in the hard granite plate cutting applications is limited, at home and abroad are investing heavily in developing the framework of large-scale diamond saw to expected to replace sand frame saws, but there is no more satisfactory results; domestic application surface of diamond wire saw very narrow, only for marble mining, segmentation plastic blocks, shaped stone processing, etc. As for granite cutting sintered diamond wire, are currently in exploratory research and experimental stage; various size diamond saw sawing granite sawing is today the most widely used mode of production, due to the circular saw blade cutting a continuous motion, high relative velocity , a combination of multi-blade, cutting efficiency is high. However, blade diameter limits the stone format width, and the centrifugal force of the blade (diamond-caking) and the base weld mechanical properties requires highly expensive large-diameter circular saw blades, low cost. Stone Material Industry Association statistics show that, at present the various types of stone companies own and use specifications in diameter Ф1600 ~ diamond circular saw equipment Ф2200mm have between 3.5 million units, the annual consumption of saw blade up to 3.5 million more than .
Third, the large-diameter diamond saw blade laser welding process
(A) machining of hard granite weld requirements
Stone saw cutting force depends on the depth of cut, head size, density diamond blade, diamond size and degree of wear and other factors, due to the high natural granite hardness, uniformity differences, so there is a big head sawing process load and irregular variable loads require weld has good mechanical properties. Through the hard granite blocks domestic processing surveys show that more than 2000mm diameter disc cutting machine maximum spindle speed is 250 ~ 300r / min, the actual speed 200r / min, the average feed rate of about 500mm / h. Since the cutting speed has little effect on the normal cutting force of the blade weld large diameter core issue is to improve the impact toughness.
Proposed (b) laser welding process
When the diamond saw blades manufactured stone products, format width smaller than the radius of the blade, the effective cutting width is generally only 30% to 35% of the diameter of the circular saw blade, the traditional method is to increase the diameter of the diamond saw blade to increase cutting depth, so as to achieve the purpose of processing large format stone products. However, the current domestic production of laser-welded blade diameter not greater than 600mm, large diameter diamond saw blade laser welding technology and equipment to be further developed.
When the conventional brazing process for welding a large diameter saw blade sawing a hard granite, since the line head relative speed 20m / s or so, poor cooling conditions, severe local heating, so the strength of the weld is limited, sawing process and reduce the need to improve the cooling conditions cutting speed and feed rate; in addition, high-frequency brazing blade life is short, and debugging tool change time consuming, resulting in low processing efficiency.
Laser welded diamond saw higher frequency brazing has obvious advantages in this field has broad prospects for development. In order to achieve the same cutting depth marble cutting and efficiency, Germany, Britain, Italy and other European powers in the hard stone processing stone cutting co-organized a feasibility study at the large granite cutting depth of cut conditions for welding the strength of the seam is one of the key issues. China is facing great development of stone industry, high-quality large-diameter diamond saw blades has a huge market potential and accelerate the application of laser welding technology in this field is the current urgent problem.