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CNC automatic circular cold saw for steel bar cutting
When purchasing a new sawing machine for material cutting, users of band saw blades should understand in detail the various performances of the band saw machine and the difference between the maximum cutting width and the optimal cutting width. "Okay. The instruction manual of this sawing machine shows that the device has the ability to cut 250mm large materials. Let's drag 250mm solid stainless steel here to see if it can be sawed?" This is the same as "Look at the new Volvo car. Is it possible to continue driving at 160 kilometers per hour? "Same. In this article, let us analyze the actual meaning of the two terms "maximum cutting amount" and "optimal cutting amount" of the band saw machine.
For each band saw blade, there is the best material specification that can be cut: this size allows the band saw to cut quickly and provides the longest band saw life. The size is determined by the guide block spacing and band saw blade rigidity. Anyone interested in sawing machine machinery will find that they will be discussed in the topic "Strength of Beam". In engineering, use formulas to calculate. These parameters include the deflection, elastic modulus, moment of inertia of the band saw blade, the load on the band saw blade, and the distance between the guide blocks. Simply put, the 27mm band saw blade is suitable for cutting materials from 100mm to 125mm wide, which is the "optimal sawing width." The optimal size range will provide you with the maximum band saw blade life for a specific size band saw blade. In fact, when sawing within the optimal size range, without a skilled operator, a band saw blade with poor quality can still cut smoothly. Sawing in the "best" size range means that the requirements of many factors may be reduced, but high-quality machined parts and effective cutting efficiency can still be obtained.
Beam strength: To calculate any "beam strength" difference, it is only necessary to consider the change in the thickness ratio of the band saw blade, and the width of the band saw blade can be cubically calculated and the difference calculated. In addition, the additional downforce required to cut wider cuts due to the increased thickness of the band saw blade must also be considered.
Compare 34mm * 1.06mm band saw blade with 27mm * 0.9mm band saw blade (with 27mm as standard unit):
27mm: 1 x 1 x 1 = 100%
34mm: (34/27) x (34/27) x (34/27) = 200%
Adding a thickness of 0.16 increases the strength: 18%
The intensity of the 34mm beam is the intensity of the 27mm beam: 218%
and many more:
41mm * 1.25 beam intensity is 193% of 34mm * 1.06
The strength of 54mm * 1.6 beam is 256% of 41mm * 1.25;
The strength of 54mm * 1.6 beam is 123% of 54mm * 1.3;
The strength of 67mm * 1.6 beam is 191% of 54mm * 1.6;
The strength of 80mm * 1.6 beam is 170% of 67mm * 1.6
All the above percentages are approximate, without considering the additional downforce required to increase chip widening.
So let's go back to our 250 sawing machine and plan to cut 250mm solid stainless steel. A 27mm band saw blade is used on the sawing machine. According to the principle of tooth pitch selection, it is best to use a 2/3 TPI pitch, use an appropriate ratio of coolant, and let the operator know the difference between grinding and sawing. By the way, the sawing machine must be in perfect working condition. Experimenters should also bring lunch, because this material is limited by the physical characteristics of the material itself, making it more difficult to cut, and it takes some time to shred it. Of course, the performance of the sawing machine determines the quality of the sawing machine. The band saw blade is limited by the sawing machine. How much tension can be applied and how to adjust the optimal position during sawing depends on the sawing machine. In addition to performance limitations, the design and manufacture of sawing machines are also very important. The high-quality 250 sawing machine can easily surpass other common sawing machines of the same specifications.
However, even with the highest quality sawing machines, the strength of the band saw blade itself is limited. Do not cut larger materials that exceed the strength of the band saw blade. If you want to cut larger materials, you should use a stronger blade. This is also the reason for manufacturing saws of different specifications. Choosing the best cutting size can process precise workpieces, thereby maximizing the service life and productivity of the band saw blade. When cutting material, the size of the material is equal to or close to the maximum sawable size of the sawing machine. Band saw blade life and cutting efficiency may be reduced by up to 50%. If you only use it occasionally, it is still acceptable, but if you must run for a long time at the maximum cutting capacity of the sawing machine, even Using high-performance band saw blades and operating under the best conditions of the sawing machine, and with high operator skill levels, the following results can be expected: long sawing time and short band saw blade life. This is like driving a Volvo at a speed of 160 kilometers per hour for a long time. The driver will also get the following results: long prison time and short life.
The feed speed of the feed system also needs to select the optimal feed speed, rather than the maximum feed speed. There are many factors that affect the operation of the band saw. For example, even if a skilled operator controls the sawing machine, even under ideal conditions, he may change from "best ability" to "maximum ability". Generally speaking, you will need to choose the sawing machine and feed system that best suits your application. The capacity of the feed system is matched with the phase sawing machine, which is designed to support the maximum size of the material that the sawing machine can cut. The maximum design cutting size is the maximum size of the material that can be cut by the sawing machine. However, because large bars often have poor straightness and the weight is concentrated in a certain part, this is not the actual sawable size for frequent use. . The maximum economic value is defined as the limit of the sawing capacity that the sawing machine can easily cut. The best sawing ability is to easily cut into the material, regardless of surface conditions or material straightness. For example, if a half-ton truck reaches its "design maximum", it can carry 2.5 tons or more; under its economic ceiling, it can carry 1.2 tons; under optimal load, it can carry 0.5 tons, if it exceeds With a half-ton limit, it is difficult for vehicles to start and parking is also difficult.
For a long time, in short, you should never choose a sawing machine, especially for difficult-to-cut materials such as stainless steel, die steel, titanium alloy, high-temperature alloys, etc., it is recommended to choose a larger one and a large specification A little band saw blade, otherwise, although the purchase cost of the sawing machine is saved, the subsequent operating costs will rise a lot, and the accumulation over a long period of time will far exceed the cost savings of the original equipment purchase.