During the welding process of the circular saw blade, the bottom of the diamond segment and the teeth of the substrate are firmly connected together to form an integral diamond saw blade. Saw blades with a diameter less than or equal to 230mm are fixed by cold pressing and sintering. For circular saw blades over 230mm, the diamond segment and the saw blade are combined by welding technology. This article introduces the three popular welding processes at present. Let everyone get better understanding of the formation of diamond circular saw blades.
Fire welding, also known as flame welding, is currently more common in some developing countries. The specific method is to put the welding lug on the substrate tooth, place the diamond segment on the welding lug, and spray a high-temperature flame through a flame spray gun to melt The welding piece and the diamond segment also show the fiery red color of the metal at high temperature, and then the diamond segment is fixed on the steel substrate by the rapid cooling of the welding plate at room temperature. This fire welding method only requires flame spray gun and fuel, and does not require other machinery, and the welding cost is extremely low, so it is widely used and is suitable for welding saw blades with a diameter of more than 900mm. Of course, fire welding also has great disadvantages. For example, the lower part of the diamond segment needs to face extremely high temperature, and the slow heating speed causes the welding time to become longer; and high temperature has a great influence on the diamond segment, such as the high temperature will carbonize the diamond, and the metal bond in the diamond segment will become unstable due to the high temperature, which will eventually cause the quality of the diamond segment to deteriorate. Moreover, this method is less safe and requires higher welders' technology, and is gradually replaced by high-frequency welding.
High-frequency welding: This welding method uses a high-frequency welding machine, which can increase the temperature in a short time. The welding part of the diamond segment will have slightly influence, but will not form the situation of excessive carbonization, so this welding method is currently the most popular. High-frequency welding requires the help of machines, and there are some conditions for welding, especially for larger diamond saw blades, which is very difficult to carry, so there are some limitations compared to fire welding. However, in saw blades for medium-sized circular saw blades (300-850mm in size), with the development and use of fully automatic welding machines, a larger scale of use has been formed.
Vacuum welding: The vacuum welding method is very different from the previous two welding methods, because this method uses infrared laser welding technology, the whole process does not need to use soldering lug , and the part of the diamond segment and the substrate is heated by infrared rays. The diamond segment is directly connected to the base body. This method will greatly reduce the area of the welding seam because the thickness of the welding lug is reduced. In strength, since there is no welding lug, this welding method is also greatly improved of the welding strength, and this welding process does not carry out high-temperature treatment on the diamond segment, which guarantees the stability of the diamond segment to the greatest extent, and will have better cutting effect and life when used, and can even be used for dry cutting. This welding process has such great advantages as well as some disadvantages. For example, it needs to be carried out in a vacuum environment, and the achievement of this environment requires higher conditions. It is difficult to weld the large-size circular saw blades; for example, it is very hard to disassemble when the diamond segments already welded on the blade; for example, the multiple utilization rate of the substrate has decreased and so on.
