What are the causes of cracks on the circular slitter blades?

Cracks on circular slitter blades can be caused by a variety of factors, with the most common ones being:
1. Material Defects: Poor quality materials or the presence of impurities in the steel used to manufacture the blades can lead to cracks forming during the manufacturing process or while in use.
2. Improper Heat Treatment: Incorrect heat treatment processes, such as overheating or rapid cooling, can result in the formation of internal stresses within the blade material, making it more susceptible to cracking.
3. Overloading: Subjecting the blades to excessive loads or cutting materials that are too hard or thick for the blades to handle can cause them to crack due to the high levels of stress and strain.
4. Wear and Tear: Continuous use of the blades without proper maintenance or sharpening can lead to wear and tear, weakening the blade structure and making it more prone to cracking.
5. Impact Damage: Accidental impacts or collisions with hard objects during operation can cause localized stress concentrations on the blade surface, leading to the formation of cracks.
6. Improper Handling: Mishandling of the blades during installation, removal, or storage can result in mechanical damage or deformation, which may ultimately lead to cracking.

circular slitter blades are widely used in ceramics, printing machinery, paper industry and other industries. They are often used for slitting articles such as paper, film and gold foil. These products have one feature: thin and soft. Therefore, to cut these products, the blade must have the minimum cutting resistance and maximum wear resistance. The cutting blade is popular because of its flexible radian and excellent material. However, in the process of use, the circular slitter blades often produce cracks, which has a great impact on the execution of slitting work. This article will introduce the causes of cracks on the circular slitter blades so that users can prevent the effects of cracks on the circular slitter blades in advance.

The following is a list of contents

1. Cracks caused by secondary heating of blade

2. Defects on the bottom surface of the cutter groove cause or aggravate cracks

3. The shape of the cutter slot can also cause cracks in the blade

Cracks caused by secondary heating of blade

The circular slitter blades are easy to crack when heated, especially after the secondary heating of the circular slitter blades, the binder of the blade is burned out, which is more likely to crack. After brazing the circular slitter blades, the red copper solder did not completely fill the gap, and individual false soldering appeared. During the discharging process of some cutters, the circular slitter blades fall off the cutter bar, so it needs to be heated by the secondary system. However, in this way, the binder Co of the blade is seriously burned and the WC grain grows gradually, which may directly lead to cracks in the slitter blade. The circular slitter blades have a circular shape and is generally used in mechanical equipment, mainly for cutting, trimming and other processing functions. The circular slitter blades usually have an intermediate hole to fix it on the mechanical equipment, so as to achieve the cutting function. There are also many types of circular slitter blades with toothed edges, such as flat teeth, sharp teeth or irregular teeth. There are three kinds of cutting edges: double-sided, single-sided and non-cutting. Therefore, we require the solder to have good dehydration, which requires the welding working temperature to be generally controlled at about 30 ~ 50 ℃ greater than the solder melting point.

Defects on the bottom surface of the cutter groove cause or aggravate cracks

Defects on the bottom surface of the cutter groove will affect the development of cracks. The contact surface between the circular slitter blades and the knife groove is uneven, such as black leather and hemp pits, local differences, etc., which makes the welding technology unable to form a plane design combination, resulting in uneven distribution of solder. This problem can not only affect the structural strength of the weld, but also affect different stress concentrations, resulting in the segment crack of the circular slitter blades. Therefore, the circular slitter blades should grind the contact surface. The welding surface of the slot of the circular slitter blades shall be cleaned. During the cooperation between the milling slot of the slitting machine and the slitting machine blade, it is required that the extension of the circular slitter blades from the support department of the cutter rod shall not be greater than 0.5mm. If the extension of the circular slitter blades from the support department of the cutter rod is too large or the capacity of the support department of the cutter rod is weak, It will make the cutting tool unable to bear the tensile force in the process of welding production and produce the phenomenon of fracture. After slow cooling, it is best to keep the temperature at about 300 ℃ for more than 6 hours and cool with the furnace. Under the basic requirements of weld strength required by enterprises, the management area of brazing surface shall be effectively reduced as far as possible.

The shape of the cutter slot can also cause cracks in the blade

The shape of the cutter groove is inconsistent with or quite different from the welding surface of the cutter bar, which will form an economic closed or semi-closed groove shape, which is easy to cause too much welding surface and too large welding layer, because the shrinkage rate after different thermal expansion is also inconsistent, which is also easy to cause the cracking of the welding part of the circular slitter blades due to the excessive change of environmental stress. After welding, we can't put the blade in raised water for rapid cooling, but put it in Chinese lime, asbestos powder, sand and other items for slow cooling.

After the above introduction, I think the readers have understood what causes the blade to crack, and also considered how to prevent the occurrence of crack. The company provides various types of blade products. If you are interested in our products, you can contact us for detailed product introduction and quotation!

By identifying and addressing these potential causes, manufacturers and users of circular slitter blades can take preventive measures to minimize the risk of cracks and ensure the longevity and effectiveness of the blades. Regular inspection, maintenance, and proper handling practices are essential to prolonging the lifespan of the blades and maintaining their cutting performance.