When using a band saw to cut H steel, I-beam, angle steel and channel steel, make sure not to cut obliquely. Once the material is cut obliquely or cored, it will affect the subsequent material welding process and cause the welder to polish the excess material. Or adding filler materials, or worse, may lead to re-cutting or material waste, which is time-consuming and costly. Therefore, when we saw the profile, we should pay attention to the following matters:
- Sawing machine maintenance
Pay attention to the daily maintenance of the sawing machine. If there is a problem with the feed system and the main drive system, the use time of the band saw will be significantly shortened, and the saw blade will also be easy to cut.
- Pay attention to setting the sawing parameters
Set the sawing parameters according to the parameter guide table of the band saw blade manufacturer or sawing machine manufacturer. Generally, the cutting efficiency of thin-walled profiles less than 10mm is only about 20% of that of the solid wood of the same height, and the feed speed is mainly It is necessary to consider the average cutting load per tooth. H steel and channel steel are generally extruded from low-carbon steel or structural steel. The following are the sawing parameters of these two typical materials:
H-steel I-beam sawing parameter table:
|200* 150||600* 200|
|Carbon steel||Line speed||48~72||41~61|
For other materials, the speed is generally set high when the material is soft, and the linear speed is set lower when the material is hard.
In addition, pay attention to the correct clamping of the material and ensure that the material is delivered by the feeding roller.
- Correctly set the band saw tension
When the general sawing machine cuts section steel, the tension is set between 170KN/cm2 ~220KN/cm2. Too small tension will cause insufficient beam strength, band saw fatigue and cutting; and excessive tension may cause early fracture of the band saw , The butt weld is broken, the tooth groove is cracked, and may cause the main bearing of the saw wheel to wear out too quickly.
- Pay attention to cutting in from the bottom weld of the weld
If there are welds in some section steels, be careful not to cut in from the upper welds. Otherwise, the weld height protruding from the upper welds will easily cause the load of the band saw in operation to increase suddenly and may cause tooth pull failure.
- Pay attention to the clamping method
When clamping, it is necessary to control the workpiece to be cut not to slide or rotate. If a single workpiece moves back and forth during the sawing process, it may also cause the band saw to pull the teeth. The general clamping method of section steel is as follows:
- Use cutting fluid correctly
The cutting fluid can not only cool down, but also prevent the formation of chips at the tip of the tooth. The cutting fluid should be covered on the entire sawing path of the workpiece. The cutting fluid will volatilize during use. The concentration of the cutting fluid should be kept at about 5% as much as possible. The concentration of the new fluid should be properly proportioned before being added to the cutting fluid pool.
- Band saw running-in
New band saws need to be run-in at the beginning of sawing section steel, and the run-in of section steel sawing is especially important, because cutting this material will vibrate and easily cause the tooth tip of the new saw blade to chip away. The author’s suggestion is to first adjust the feed speed of the band saw to 10% of the normal value during initial sawing, instead of the 50% set in the conventional running-in mode (because the feed speed of the section steel is much faster), the line speed does not need to be adjusted , Gradually increase the feed speed to 100% during the sawing process. The life of a saw blade that is properly run-in may be about twice the life of a saw blade that is not properly run-in.
- Choose a suitable saw blade
At present, there are anti-tension teeth and sharp tooth saw blades on the market. For thin-walled steel with a thickness of less than 10mm, the main choice is to choose anti-tension teeth. For those with a thickness of 10mm or more, it can be determined according to efficiency requirements and sawing conditions. In the case of pulling teeth, the anti-pull tooth and the tortoise tooth are used, and the tines can also be used in the case of no pulling tooth failure.
If the material is stainless steel or alloy steel, you can choose a sharp tooth with a smaller pitch, because the feed speed is significantly reduced, such as sawing a stainless steel tube with a wall thickness of 2mm, using a 6/10 sharp tooth can also be used for good sawing results. . For section steel made of medium and low carbon steel, it is not recommended to use a tooth profile with a large rake angle.
If you are pursuing high-efficiency sawing, low-end saw blades often cannot meet the requirements of back strength and machining accuracy. It is recommended to choose LB-AA and above product series.
In the selection of tooth pitch, choosing a larger tooth pitch can improve the sawing efficiency, and choosing a smaller tooth pitch will make the machining surface of the workpiece smoother.
If there is a serious clamping or jamming phenomenon, you need to order a product with an increased amount of divided teeth. Generally, this kind of jamming phenomenon is easy to appear in the sawing of large and medium-sized I-beams.
- Selection of sawing machine
ANTS MACHINE’s sawing machine has a special sawing machine for cutting section steel. If you are processing more units of H steel, I-beam, and channel steel, it is recommended to choose a sawing machine with a certain inclination of the head. This kind of sawing machine can make the saw blade in the entire sawing stroke. The medium load is more uniform, preventing chip removal when the tooth groove is cut to the position of the web, and the saw gap can be kept smaller.