The high-speed paperboard production line has always been valued by the personnel in the industry, and the slitting part of the thin knife is particularly important, and the application of the thin knife greatly improves the quality of paperboard. Therefore, it is particularly important to select enough thin knife and its supporting consumables, which directly affects the quality and output of paperboard. At present, there are only two categories of slitting thin knives among many manufacturers in China:

Class I: tool steel

It is also divided into:

1.: w6mn5cr4v2 --- tungsten 6 manganese 5 chromium 4 vanadium 2 high speed tool steel (commonly known as Feng)

2.: Cr12 --- chromium steel (commonly known as die steel)

3.: 9SiCr --- 9 silicon chromium alloy tool steel (commonly known as tool steel, 9 chromium silicon)

After quenching treatment, although the Rockwell hardness of the above tool steel slitting thin knives is less than a few degrees, the raw material price and manufacturing cost vary greatly due to different chemical elements of the steel. However, in the market, many manufacturers choose edge steel knife, because edge steel thin knife has high temperature resistance, good toughness and unique red hardness, and the knife edge remains sharp and lasting. It has superior performance compared with other tool steel thin knives, but the price is also higher.

Class II: cemented carbide thin knife (commonly known as tungsten steel knife)

Cemented carbide is divided into tungsten cobalt and tungsten cobalt titanium. Generally, the blade produced in China is tungsten cobalt (YG), which has large raw materials and manufacturing costs. It has high hardness, good wear resistance and longer service life, but it is expensive because it has no toughness and low bending strength. How to reasonably purchase slitting thin knives depends on their own equipment conditions. For some old equipment, we suggest to use steel thin knives, because these equipment usually can not meet the accuracy required by cemented carbide blades. Low speed wire machine (less than 60m / min) does not need to choose high-speed steel thin knife. Chromium steel thin knife also has good cost performance, which is more suitable for single machines with small workload. For manufacturers with good equipment, of course, using cemented carbide thin knife is the best choice. It has a long service life and short grinding time, which greatly reduces the times of shutdown and tool change in the production process, leaving time and things, and greatly reduces the production cost.

When purchasing blade steel thin knife, we should pay attention to the material of its steel and the thickness of the blade. The thickness of the blade should generally be between 1.2mm-1.3mm. When purchasing, don't think imported blades are good. In fact, due to the different sand content of corrugated board at home and abroad, the service life of imported thin knives is greatly reduced. Moreover, due to the low accuracy and stability of domestic equipment, the service performance of imported thin knives is further discounted. Moreover, due to tariff and other factors, the price is also very high. The thickness of imported thin knives is usually 1.1mm. Domestic thin knives with a thickness of 1.25mm-1.3mm are selected. Their slitting quality and blade service life are almost the same as those of similar foreign products. For the carbide slitting thin blade, its service life should ensure that the slitting paperboard is about 5-6.5 million meters. Although the input cost of this blade is large, compared with the cutting thin knife of Fenggang, the output of paperboard is greatly increased and the linear speed is greatly improved, but the requirements for equipment are very high.

Due to the different production processes of various manufacturers, the quality and alloy composition of cemented carbide slitting thin knife are also different. Cemented carbide slitting thin knife, which is mainly composed of three elements of "tungsten, carbon and cobalt", is made by pressing and sintering powder. Therefore, at present, some domestic manufacturers call it "tungsten steel" slitting thin knife. Due to the unique performance of cemented carbide slitting thin knife, the following points should be paid attention to in the process of purchase and use:

The selection of carbide slitting thin knife shows that the finish must meet the mirror standard. When the paperboard passes through the slitter, the adhesive is often not fully cured, so it is inevitable to adhere to the blade. The blade with high surface finish is easy to remove the dirt. Otherwise, over time, the residual adhesive on the blade surface will form hard adhesive scale after curing, which will affect the paper cutting quality of the blade. The selection of carbide slitting thin knife should match the accuracy level of the equipment. For thin knife slitting machines with low precision and slow speed, it is recommended not to use cemented carbide slitting thin knife, because on such equipment, the service life of the blade is often shortened due to the interference of mechanical and other factors. If the end face runout of the thin knife mounting base on the equipment is within 0.1mm (if the end face runout of the thin knife mounting base exceeds 0.1mm or improper operation, the blade will be brittle and cause loss), the linear speed of the production line is high, and the carbide slitting thin knife will be a good choice.