Factors affecting the efficiency and life of diamond saw blades

Factors affecting the efficiency and life of diamond saw blades include sawing process parameters, diamond particle size, concentration, and bond hardness. According to the cutting energy, there are saw blade line speed, sawing density and feed speed.

1. Sawing parameters

(1) Linear speed of the saw blade: In actual work, the linear speed of the diamond circular saw blade is limited by the equipment conditions, the quality of the saw blade and the nature of the stone being sawed. From the perspective of optimal saw blade service life and sawing efficiency, the linear speed of the saw blade should be selected according to the properties of different stone materials. When sawing granite, the linear speed of the saw blade can be selected within the range of 25m to 35m/s. For granite with quartz content that is difficult to saw, the lower limit of the linear speed of the saw blade is appropriate. When producing granite tiles, the diameter of the diamond circular saw blade used is small, and the linear speed can reach 35m/s.

(2) Sawing depth: Sawing depth is an important parameter involving diamond wear, effective sawing, force of the saw blade and the properties of the stone being sawed. Generally speaking, when the linear speed of the diamond circular saw blade is relatively high, a small cutting depth should be selected. From the current technology, the depth of sawing diamond can be selected between 1mm and 10mm. Generally, when cutting granite blocks with large-diameter saw blades, the cutting depth can be controlled between 1mm and 2mm, and at the same time, the feed speed should be reduced. When the linear speed of the diamond circular saw blade is large, a large depth of cut should be selected. However, within the allowable range of saw machine performance and tool strength, a larger cutting concentration should be used for cutting to improve cutting efficiency. When there is a requirement for the machined surface, a small depth cut should be used.

(3) Feed speed: The feed speed is the feed speed of the stone being sawed. Its size affects the cutting rate, the force on the saw blade, and the heat dissipation in the sawing area. Its value should be selected according to the nature of the stone being sawn. Generally speaking, when sawing soft stone, such as marble, the feed speed can be appropriately increased. If the feed speed is too low, it is more conducive to increase the sawing rate. When sawing fine-grained, relatively homogeneous granite, the feeding speed can be appropriately increased. If the feeding speed is too low, the diamond blade will be easily ground. However, when sawing granite with a coarse-grained structure and uneven hardness, the feed speed should be reduced, otherwise it will cause the saw blade to vibrate and cause the diamond to break and reduce the sawing rate. The feed speed for sawing granite is generally selected within the range of 9m to 12m/min.

2. Other influencing factors

(1) Diamond particle size: The commonly used diamond particle size is in the range of 30/35 to 60/80. The harder the rock, the finer grain size should be selected. Because under the same pressure conditions, the finer and sharper the diamond is, which is conducive to cutting into hard rocks. In addition, generally large-diameter saw blades require sawing efficiency, and a coarser particle size should be selected, such as 30/40, 40/50; small-diameter saw blades have low sawing efficiency and require smooth rock sawing sections. Finer granularity like 50/60, 60/80.

(2) Concentration of cutter head: The so-called diamond concentration refers to the density of diamonds distributed in the working layer matrix (that is, the weight of diamonds contained in a unit area). The "Specification" states that the concentration of 4.4 carats of diamond per cubic centimeter of working matrix is 100% and that of 3.3 carats of diamond is 75%. The volume concentration indicates the volume of diamond in the agglomerate, and it is stipulated that when the volume of diamond accounts for 1/4 of the total volume, the concentration is 100%. Increasing the diamond concentration is expected to prolong the life of the saw blade because increasing the concentration reduces the average cutting force per diamond. However, increasing the depth will inevitably increase the cost of the saw blade, so there is an economical concentration, and the concentration increases with the increase of the cut rate.

(3) Hardness of the cutter head bond: Generally speaking, the harder the bond, the stronger its wear resistance. Therefore, when sawing abrasive rocks, the binder hardness should be appropriate; when sawing soft rocks, the binder hardness should be low; when sawing abrasive and hard rocks, the binder hardness should be moderate.

(4) Force effect, temperature effect and grinding damage: During the process of cutting stone, the diamond circular saw blade will be subjected to alternating loads such as centrifugal force, sawing force, and sawing heat.

The wear and tear of the diamond circular saw blade is caused by the force effect and the temperature effect. Force effect: During the sawing process, the saw blade is subjected to the action of axial force and tangential force. Due to the force in the circumferential and radial directions, the saw blade is wavy in the axial direction and dish-shaped in the radial direction. These two kinds of deformation will cause uneven rock section, waste of stone material, loud noise and intensified vibration during sawing, resulting in early damage of diamond agglomeration and shortening of saw blade life.