Carbide saw blades are the most commonly used cutting tools for wood product processing. The quality of carbide saw blades is closely related to the quality of processed products. Correct and reasonable selection of carbide saw blades can improve product quality, shorten processing cycles, and reduce processing costs. Carbide saw blades include multiple parameters such as the type of alloy cutter head, material of the matrix, diameter, number of teeth, thickness, tooth shape, angle, aperture, etc. These parameters determine the processing capability and cutting performance of the saw blade. When choosing a saw blade, you must choose the correct saw blade according to the type, thickness, sawing speed, sawing direction, feeding speed, and sawing path width of the material being cut. So how should it choose?
(1) Selection of cemented carbide types
Commonly used types of cemented carbide include tungsten-cobalt and tungsten-titanium. Tungsten-cobalt carbide has good impact resistance and is widely used in the wood processing industry. As the cobalt content increases, the impact toughness and flexural strength of the alloy increase, but the hardness and wear resistance decrease. The selection should be based on the actual situation. (2) Selection of matrix
1. 65Mn spring steel has good elasticity and plasticity, economical material, good heat treatment hardenability, low heating temperature and easy deformation, so it can be used for saw blades with low cutting requirements.2. Carbon tool steel contains high carbon and has high thermal conductivity, but its hardness and wear resistance drop sharply when exposed to temperatures of 200°C-250°C. It suffers from large heat treatment deformation, poor hardenability, and long tempering time and is prone to cracking. Make economical materials for cutting tools such as T8A, T10A, T12A, etc.3. Compared with carbon tool steel, alloy tool steel has good heat resistance, wear resistance and better processing performance. The heat-resistant deformation temperature is 300℃-400℃, which is suitable for manufacturing high-grade alloy circular saw blades.
(3) Selection of diameter
The diameter of the saw blade is related to the sawing equipment used and the thickness of the workpiece being cut. The diameter of the saw blade is small, and the cutting speed is relatively low; the diameter of the saw blade is high, and the requirements for the saw blade and sawing equipment are high, and the sawing efficiency is also high. The outer diameter of the saw blade should be selected according to different circular saw machine models. Use a saw blade with a consistent diameter. (4) Selection of number of teeth
The number of teeth of the saw teeth. Generally speaking, the more teeth there are, the more cutting edges can be cut per unit time and the better the cutting performance. However, more cutting teeth require more cemented carbide, and the price of the saw blade will be higher, but the saw teeth are too dense. , the chip capacity between the teeth becomes smaller, which can easily cause the saw blade to heat up; in addition, there are too many saw teeth, and when the feed rate is not matched properly, the amount of cutting per tooth will be very small, which will intensify the friction between the cutting edge and the workpiece, affecting the service life of the blade. . Usually the tooth spacing is 15-25mm, and a reasonable number of teeth should be selected according to the material being sawed. (5) Choice of thickness
The thickness of the saw blade: In theory, we hope that the saw blade should be as thin as possible. The saw kerf is actually a consumption. The material of the alloy saw blade base and the process of manufacturing the saw blade determine the thickness of the saw blade. If the thickness is too thin, the saw blade will easily shake during operation, affecting the cutting effect. When choosing the thickness of the saw blade, you should consider the stability of the saw blade and the material being cut. Some materials for special purposes also require specific thicknesses and should be used according to equipment requirements, such as grooving saw blades, scribing saw blades, etc.
(6) Selection of tooth shape
Commonly used tooth shapes include left and right teeth (alternating teeth), flat teeth, trapezoidal teeth (high and low teeth), inverted trapezoidal teeth (inverted conical teeth), dovetail teeth (hump teeth), and the rare industrial-grade triangular teeth. Left and right, left and right, left and right flat teeth, etc.
1. The left and right teeth are the most widely used, with fast cutting speed and relatively simple grinding. It is suitable for cutting and cross sawing various soft and hard solid wood profiles and density boards, multi-layer boards, particle boards, etc. The left and right teeth equipped with anti-rebound protection teeth are dovetail teeth, which are suitable for longitudinal cutting of various boards with tree knots.The left and right tooth saw blades with negative rake angles are usually used for sawing veneer panels due to their sharp teeth and good sawing quality.
2. The flat-tooth saw edge is rough and the cutting speed is slow, so it is the easiest to grind. It is mainly used for sawing ordinary wood with low cost. It is mostly used for aluminum saw blades with smaller diameters to reduce adhesion during cutting, or for grooving saw blades to keep the groove bottom flat.
3. The trapezoidal teeth are a combination of trapezoidal teeth and flat teeth. The grinding is more complicated. It can reduce the cracking of the veneer during sawing. It is suitable for sawing various single and double veneer artificial boards and fireproof boards. Aluminum saw blades often use trapezoidal saw blades with a larger number of teeth to prevent adhesion.
4. Inverted ladder teeth are often used in the bottom groove saw blade of panel saws. When sawing double-veneered artificial boards, the groove saw adjusts the thickness to complete the groove processing of the bottom surface, and then the main saw completes the sawing process of the board. Prevent edge chipping at the saw edge.To sum up, when sawing solid wood, particleboard, or medium-density board, you should choose left and right teeth, which can sharply cut off the wood fiber tissue and make the cut smooth; in order to keep the groove bottom flat, use flat teeth or left and right teeth. Combination teeth; when cutting veneer panels and fireproof boards, trapezoidal teeth are generally used. Due to the high cutting rate, the computer cutting saw uses an alloy saw blade with a relatively large diameter and thickness, with a diameter of about 350-450mm and a thickness of 4.0-4.8 mm, most use stepped flat teeth to reduce edge chipping and saw marks.
(7) Selection of sawtooth angle
The angle parameters of the sawtooth part are relatively complex and the most professional, and the correct selection of the angle parameters of the saw blade is the key to determining the quality of sawing. The most important angle parameters are rake angle, back angle and wedge angle.The rake angle mainly affects the force consumed in sawing wood chips. The larger the rake angle, the better the cutting sharpness of the saw teeth, the lighter the sawing, and the easier it is to push the material. Generally, when the material to be processed is soft, choose a larger rake angle, otherwise choose a smaller rake angle.
(8) Selection of aperture
The aperture is a relatively simple parameter, which is mainly selected according to the requirements of the equipment. However, in order to maintain the stability of the saw blade, it is best to use equipment with a larger aperture for saw blades above 250MM. At present, the apertures of standard parts designed in China are mostly 20MM holes with diameters of 120MM and below, 25.4MM holes with diameters of 120-230MM, and 30mm holes with diameters above 250. Some imported equipment also has 15.875MM holes. The mechanical aperture of multi-blade saws is relatively complex. , many are equipped with keyways to ensure stability. Regardless of the size of the hole, it can be modified through a lathe or wire cutting machine. The lathe can turn washers into the large hole, and the wire cutting machine can expand the hole to meet the requirements of the equipment.
A series of parameters such as the type of alloy cutter head, the material of the base body, diameter, number of teeth, thickness, tooth shape, angle, aperture, etc. are combined to form the entire carbide saw blade. It must be reasonably selected and matched to better utilize its advantages.
