A carbide band saw blade

Abstract

The present invention discloses a carbide band saw blade, comprising 18 saw teeth arranged adjacently and sequentially to form a tooth arrangement cycle, wherein within a tooth arrangement cycle, the first, fourth, seventh, tenth, thirteenth and sixteenth saw teeth are straight teeth, and each straight tooth is followed by two left and right divided teeth; wherein the heights of the first, tenth, fourth, thirteenth, seventh and sixteenth saw teeth decrease in sequence, and by controlling the different heights of the teeth and the amount of divided teeth, the tooth profile of the present invention divides the chips into 23 pieces of chips during cutting. The present invention makes the coarse and thick chips thinner and reduces the cutting force during cutting by designing the tooth profile, and by combining the anti-wear tooth profile design, the sawing life is extended, and the problems of cutting bevel and rough section caused by excessive wear and micro-collapse of the tooth tip are avoided.

Description

Technical Field

[0001] The invention relates to a carbide band saw blade, belongs to the field of sawing metal tools, and in particular to a carbide band saw for sawing large-section mold steel. Background Art

[0002] In the mold steel industry, as the quality of mold steel in my country improves, the consumption of mold steel related products needs to be updated and upgraded, which has driven the demand for high-end mold steel products. Molds are the main processing tools for manufacturing parts in industrial sectors such as machinery manufacturing, radio instruments, motors, and electrical appliances. Mold steel is widely used in manufacturing fields such as machinery, electronics, automobiles, aerospace, and energy. Now, the level of the mold industry has become an important indicator of the level of a country's manufacturing industry, and it is also one of the important guarantees for a country's industrial products to maintain international competitiveness.

[0003] As rough machining of die steel, especially high carbon and high chromium cold working die steel, it is very difficult to process. For carbide sawing, when high cutting efficiency is required, especially for ultra-large cross-section die steel, the main problem is excessive wear of the tooth tip, poor cutting resistance, inability to cut, oblique cutting, and digging, which leads to the failure of the saw blade.

[0004] From the perspective of cemented carbide product development, there are currently two main types of cemented carbide band saw blades: divided-tooth and non-divided-tooth. For horizontal sawing of ultra-large cross-section workpieces, divided-tooth cemented carbide saw blades are mainly used.

[0005] From the perspective of tooth shape design, there are mainly three-chip standard type and multi-chip type for divided-tooth carbide saw blades, among which the multi-chip type has 7-chip type and 11-chip type. From the perspective of cutting force, the cutting force of multi-chip carbide during sawing is significantly lower than that of three-chip standard type, and the more divided chips there are, the smaller the cutting force.

[0006] In a large domestic mold steel processing company, some products are processed using bimetallic band saw blades, but the processing efficiency of bimetallic band saw blades is very low. Taking the sawing of 1500mm (width) * 1200mm (height) cold-working mold steel as an example, it takes 12 hours to saw one cut, which seriously affects the delivery speed and the progress of downstream processing. Usually, the sawing efficiency of the split-tooth carbide band saw blade is 2-5 times that of bimetal. The processing time of the split-tooth carbide band saw blade is about 4-5 hours, which greatly improves the processing efficiency. At present, the sawing life of the split-tooth series of carbide band saw blades when sawing large-section mold steel is 3-4㎡. Its failure mode is mainly due to excessive wear of the tooth tip, micro-chipping of the tooth tip, etc., which causes the cutting bevel (verticality), wavy cut surface, and roughness.

[0007] At present, the three-chip standard type and multi-chip type (7-chip, 11-chip) carbide band saw blades with different teeth cannot withstand high sawing efficiency due to the excessive cutting force of single tooth, and at the same time cannot solve the problem of excessive wear of tooth tip and excessive wavy lines on the cut surface. When using three-chip standard carbide, the chips are relatively coarse and thick. When sawing mold steel, the cutting resistance of single tooth is large and cannot withstand excessive sawing efficiency, which is most likely to cause accelerated wear of tooth tip; when using 7-chip and 11-chip, although the chips are small and thin, they can significantly reduce the cutting force compared with three-chip, but overall, the wear resistance of tooth tip is not strong, the micro-chipping of tooth tip edge increases, resulting in excessive wear, causing saw teeth to be unable to cut, and then there will be cutting bevel, cross-section wavy lines and other phenomena.

[0008] The inventor's prior invention patent (publication number: CN111054977B) discloses a multi-chip carbide band saw blade for sawing large-section stainless steel. When it is used to saw large-section mold steel, there is a risk of beveling. Summary of the invention

[0009] In order to solve the technical problem of easy beveling when sawing super large sections (especially sawing large section mold steel), the present invention provides a carbide band saw blade, which, through the design of the tooth shape, makes the coarse and thick chips in the prior art thinner, reduces the cutting force during cutting, and prolongs the sawing life. The specific technical solution is as follows.

[0010] A carbide band saw blade, comprising a saw blade body and saw teeth on the saw blade body, characterized in that 18 saw teeth arranged adjacently in sequence form a tooth arrangement period, within a tooth arrangement period, the first, fourth, seventh, tenth, thirteenth and sixteenth saw teeth are straight teeth, the second, fifth, eighth, eleventh, fourteenth and seventeenth saw teeth are left-split teeth, and the third, sixth, ninth, twelfth, fifteenth and eighteenth saw teeth are right-split teeth;

[0011] The heights of the first, tenth, fourth, thirteenth, seventh and sixteenth saw teeth decrease in sequence, the heights of the fifth, second and eleventh saw teeth also decrease in sequence, and the heights of the fifth and sixth saw teeth are the same, the heights of the second, third, eighth, ninth, fourteenth and fifteenth saw teeth are the same, and the heights of the eleventh, twelfth, seventeenth and eighteenth saw teeth are the same;

[0012] Both sides of the first, fourth, tenth and thirteenth saw teeth are provided with chamfers, and the outer sides of the fifth and sixth saw teeth are provided with chamfers.

[0013] Furthermore, the inclination angles of the chamfers on both sides of the first, fourth, tenth and thirteenth saw teeth are the same, the top widths of the first saw tooth and the tenth saw tooth are the same, the top widths of the fourth saw tooth and the thirteenth saw tooth are the same, and the top width of the first saw tooth is smaller than the top width of the fourth saw tooth.

[0014] Furthermore, the second, third, seventh, eighth, ninth, eleventh, twelfth, fourteenth, fifteenth, sixteenth, seventeenth and eighteenth saw teeth are not chamfered.

[0015] Furthermore, the saw teeth include cutting edges formed of cemented carbide.

[0016] Furthermore, the heights of the first, tenth, fourth, thirteenth, seventh and sixteenth saw teeth decrease in an arithmetic progression, and the arithmetic progression gradient is 0.05 mm.

[0017] Furthermore, the sawtooth front angle of the band saw blade is 10°-20°, preferably 15°; the sawtooth back angle is 10°-30°, preferably 25°.

[0018] Furthermore, some of the tooth tips are passivated. The passivation treatment is to grind the edge of the tooth tip so that a small platform is formed at the edge, which can reduce the vibration of the saw blade during sawing and form a good sawing surface quality.

[0019] Compared with the prior art, the present invention has the following beneficial effects.

[0020] 1. The 18-tooth / group tooth design and 23 chip counts further reduce the cutting force during sawing compared to the existing multi-chip band saw blades. Compared to the existing technology, the number of teeth is increased from 15 to 18. On the one hand, because the mold steel has a certain internal stress, it is necessary to increase the number of teeth to form a saw path to avoid the band saw blade from getting stuck during operation. On the other hand, because it is very easy to cause wear and chipping of the tooth tip when sawing mold steel, the corresponding number of teeth is increased to reduce the cutting resistance of a single saw tooth.

[0021] 2. Increasing the number of middle teeth (straight teeth) compensates for the wear of the middle teeth when subjected to large cutting forces, reduces longitudinal vibration during sawing, and reduces the risks of cutting failure, poor cutting resistance, and bevel cutting;

[0022] 3. The design of increasing the number of eccentric teeth (split teeth) compensates for the wear of the side edges of the tooth tips, reduces the lateral vibration during sawing, and reduces the risk of oblique cutting and core digging;

[0023] 4. Adding passivation treatment to the tooth tip edge can effectively reduce vibration, ensure smooth sawing cut surface, and enhance the anti-micro-collapse performance of the tooth tip edge. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The tooth profile design diagram of the band saw blade of the present invention;

[0025] Figure 2 A tooth height diagram of the band saw blade of the present invention;

[0026] Figure 3 It is a cutting schematic diagram of the band saw blade of the present invention;

[0027] Figure 4 It is a schematic diagram of the tooth distribution of the band saw blade of the present invention;

[0028] Figure 5 Schematic diagram of the relationship between chip thickness and cutting force. DETAILED DESCRIPTION

[0029] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0030] See also Figure 1-5 A carbide band saw blade comprises a saw blade body (back material) and saw teeth on the saw blade body, wherein 18 adjacent saw teeth are arranged in sequence to form a tooth arrangement cycle (main tooth group), within which the first, fourth, seventh, tenth, thirteenth and sixteenth saw teeth are straight teeth, the second, fifth, eighth, eleventh, fourteenth and seventeenth saw teeth are left-split teeth, and the third, sixth, ninth, twelfth, fifteenth and eighteenth saw teeth are right-split teeth.

[0031] Tooth tip shape Figure 1 As shown, the tooth shape design consists of 18 teeth / group, and each group of teeth contains 6 straight teeth. Among them, the teeth of 1#, 4#, 10#, and 13# are chamfered on both sides, and the inclination angle of the chamfer is the same. The teeth of 7# and 16# are not chamfered, and the top widths of the 1# and 10# teeth are the same, the top widths of the 4# and 3# teeth are the same, and the top width of the 1# tooth is smaller than the top width of the 4# tooth; each group of teeth contains 12 split teeth (biased teeth), and the split teeth are caused by the split tooth mold hitting the belt body to the left / right. Among the split teeth, one side of the 5# and 6# teeth is chamfered, and the 5# and 6# teeth are designed with a small split tooth amount; the 2#, 3#, 8#, 9#, 11#, 12#, 14#, 15#, 17#, and 18# teeth are not chamfered, and a large split tooth amount design is adopted.

[0032] like Figure 1 and Figure 2 As shown, in the tooth shape design, among the straight teeth, the 1# tooth is the highest tooth, and the heights of the 1#, 10#, 4#, 13#, 7#, and 16# teeth decrease in sequence, and decrease in an arithmetic gradient of 0.05mm; for the split teeth, the 5# tooth and the 6# tooth have the same height, the 11#, 12#, 17#, and 18# teeth have the same height, the 2#, 3#, 8#, 9#, 14#, and 15# teeth have the same height, and the heights of the 5#, 2#, and 11# teeth decrease in sequence; the lateral inclination angles of all the split teeth are the same, and the heights of the parts of the split teeth involved in cutting are all lower than the height of the 16# tooth. The present invention enhances the cutting ability of the middle teeth and reduces the risk of cutting obliquely by setting multiple levels of height difference.

[0033] In the 18-tooth / group design, the saw path width is Kerf (see Figure 4 ), 2#, 3#, 8#, 9#, 14#, 15# teeth are all designed with the same and maximum number of teeth (see Figure 4 In W1), although the 5# and 6# teeth are designed with the same tooth spacing as the 2#, 3#, 8#, 9#, 14#, and 15# teeth, the tooth spacing (see Figure 4 In the end, W2) must be smaller than the tooth spacing of 2#, 3#, 8#, 9#, 14#, and 15# teeth.

[0034] The chips produced by teeth 1# to 18# are shown in Figure 3 As shown. During the sawing process, 1# to 18# teeth produce a total of 23 chips, chip1-chip23, among which 1# and 10# teeth produce the thickest chips, and 2#, 3#, 8#, 9#, 11#, 12#, 14#, 15#, 17# and 18# teeth produce the thinnest chips. From the distribution of chips, the thick and short chips are mainly distributed on the straight teeth, while the thin and long chips are mainly distributed on the eccentric teeth.

[0035] In order to enhance the wear resistance and bevel resistance of the tooth tip, ensure a smooth cut surface and extend the service life of the saw blade, during the sawing process, straight teeth can enhance the saw blade's ability to resist bevel cutting during operation, while offset teeth ensure a smooth cut surface. Therefore, in this case, the number of middle teeth is increased to 6, mainly to enhance its bevel resistance performance, and the number of offset teeth is increased to 12, so that it can share less sawing resistance during the sawing process, making the chips thinner and more slender, and the cut surface smoother.

[0036] In order to enhance the performance of the tooth tip in resisting micro-collapse, some tooth tips are passivated. On the one hand, this can reduce the vibration of the saw blade during the sawing process, reduce the lateral and longitudinal jump of the saw blade during the sawing process, and ensure a smooth sawing section; on the other hand, there is no stress concentration on the cutting edge after passivation, which can prevent micro-collapse of the tooth tip.

[0037] like Figure 2 As shown in the figure, the sawtooth rake angle α is mainly used for the penetration of the workpiece during the cutting process. Generally, the larger the rake angle, the better the penetration. The size of the rake angle can improve the cutting force. The larger the rake angle, the smaller the cutting force on the sawtooth during the cutting process. The range of the rake angle α is generally -5° to 20°. In this embodiment, the rake angle α is 10° to 20°, preferably 15°.

[0038] The sawtooth back angle β during the cutting process mainly affects the anti-vibration ability and the cutting force in the feed direction. Generally, the larger the back angle, the worse the anti-vibration ability and the smaller the cutting force in the feed direction; in addition, the larger the back angle, the smaller the friction between the back tool face and the workpiece, and the cutting fluid can better enter between the tooth tip and the workpiece during sawing, which has a better heat dissipation effect, can better reduce the temperature of the tooth tip, and reduce the wear of the tooth tip edge. The range of the back angle β is generally 1° to 30°. In this embodiment, since the cutting force in the feed direction is not large, the back angle β is 10° to 30°, preferably 25°.

[0039] According to the paper "Simulation of the Intermittent Cutting Action of a Bandsaw Blade" published by M.Sarwar, H.Hellbergh, AR Doraisingam, M.Persson et al., we can establish the relationship between chip thickness and cutting force in the corresponding sawing process, such as Figure 5 As shown, the square dots represent the theoretical values ​​of cutting force, and the round dots represent the actual and corrected values.

[0040] According to the relationship between cutting force and chip thickness, the cutting force of common carbide tooth shapes is calculated, and the cutting force of each tooth shape is obtained, as shown in Table 1 below:

[0041] Table 1 Comparison of chip force and cutting number of different tooth rows

[0042]

[0043] It can be seen from the above table that the cutting force borne by the tooth design of the present application is the lowest. From the perspective of the overall tooth design, not only is the cutting force borne by the tooth portion the lowest, but the wear resistance is also improved by increasing the center teeth and offset teeth.

[0044] The present invention makes the original coarse and thick chips thinner by designing the tooth shape, reduces the cutting force during cutting, and with the anti-wear tooth shape design, the sawing life is extended, avoiding problems such as cutting bevel and rough section caused by excessive wear and micro-collapse of the tooth tip. It is very suitable for sawing of super-large cross-section workpieces, with high sawing efficiency and long saw blade service life.

[0045] The embodiments of the present invention are described above in conjunction with the accompanying drawings. In the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention is not limited to the above-mentioned specific implementations, which are merely illustrative and not restrictive. Under the enlightenment of the present invention, those skilled in the art can also make many forms without departing from the scope of protection of the present invention and the claims, all of which belong to the protection scope of the present invention.

Claims

1. A carbide band saw blade, comprising a saw blade body and saw teeth on the saw blade body, characterized in that: The 18 saw teeth arranged adjacently in sequence form a tooth arrangement cycle. In a tooth arrangement cycle, the first, fourth, seventh, tenth, thirteenth and sixteenth saw teeth are straight teeth, the second, fifth, eighth, eleventh, fourteenth and seventeenth saw teeth are left-split teeth, and the third, sixth, ninth, twelfth, fifteenth and eighteenth saw teeth are right-split teeth. The heights of the first, tenth, fourth, thirteenth, seventh and sixteenth saw teeth decrease in sequence, the heights of the fifth, second and eleventh saw teeth also decrease in sequence, and the heights of the fifth and sixth saw teeth are the same, the heights of the second, third, eighth, ninth, fourteenth and fifteenth saw teeth are the same, and the heights of the eleventh, twelfth, seventeenth and eighteenth saw teeth are the same; Both sides of the first, fourth, tenth and thirteenth saw teeth are provided with chamfers, and the outer sides of the fifth and sixth saw teeth are provided with chamfers.

2. A carbide band saw blade according to claim 1, characterized in that: The chamfers on both sides of the first, fourth, tenth and thirteenth saw teeth have the same inclination angles, the first saw tooth and the tenth saw tooth have the same top width, the fourth saw tooth and the thirteenth saw tooth have the same top width, and the top width of the first saw tooth is smaller than the top width of the fourth saw tooth.

3. A carbide band saw blade according to claim 1, characterized in that: The second, third, seventh, eighth, ninth, eleventh, twelfth, fourteenth, fifteenth, sixteenth, seventeenth and eighteenth saw teeth are not chamfered.

4. A carbide band saw blade according to claim 1, characterized in that: The saw teeth include cutting edges formed of cemented carbide.

5. The carbide band saw blade according to claim 1, characterized in that: The heights of the first, tenth, fourth, thirteenth, seventh and sixteenth saw teeth decrease in an arithmetic progression, and the arithmetic progression gradient is 0.05 mm.

6. The carbide band saw blade according to claim 1, characterized in that: The saw tooth rake angle of the band saw blade is 10°-20°.

7. A carbide band saw blade according to claim 6, characterized in that: The saw tooth clearance angle of the band saw blade is 10°-30°.

8. The carbide band saw blade according to claim 1, characterized in that: Some of the tooth tips have been blunted.

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