The slitting round knife is a key cutting tool used in the paper industry for paper slitting and cutting. Its high precision, wear resistance, and stability directly affect the processing quality and production efficiency of paper. The following are the main application scenarios and characteristics of slitting circular knives in the paper industry:
1、 Raw paper cutting and processing
1. Cut large paper rolls into small size paper rolls
Application scenarios:
     The raw paper produced by paper mills is usually produced in the form of large paper rolls with a width of several meters and a weight of several tons. It needs to be longitudinally cut into several narrow paper rolls (such as photocopy paper, packaging paper, printing paper, etc.) using a slitting machine and a slitting circular knife.
     Example: Cut the raw paper with a width of 3 meters into thermal printing paper rolls with a width of 80mm, corrugated paper rolls for cardboard boxes with a width of 500mm, etc.
Tool features:
     Multi blade combination: Multiple sets of circular blades are installed on the slitting machine, and multiple target widths of paper rolls can be cut at once by adjusting the blade spacing.
     High hardness and wear resistance: The blade is made of high-speed steel (HSS) or hard alloy (such as tungsten steel) material, with a surface treated with a coating (such as titanium nitride TiN), which can withstand continuous cutting of tens of thousands of meters of paper, reducing the risk of wear and breakage.
2. Horizontal cutting to a fixed length
Application scenarios:
     At the end or slitting stage of the paper production line, a continuous paper web is horizontally cut into fixed length flat paper (such as A4 paper, news paper, industrial paper, etc.).
     Example: Printing paper needs to be cut according to the standard size (such as 787mm × 1092mm), and the cutting round knife and the bottom knife are used to complete the cutting.
Tool features:
     High requirement for blade flatness: The gap between the round blade and the bottom blade should be controlled at 0.01-0.03mm to ensure that the incision is free of burrs and does not tear the paper.
     Dynamic balance performance: When rotating at high speeds (up to 2000-5000 revolutions per minute), balance must be maintained to avoid vibration that may cause deviation in cutting accuracy.
2、 Specialty paper and deep processing field
1. Slitting of coated paper/film composite paper
Application scenarios:
     Coated paper (such as copperplate paper, thermal paper) or composite paper (paper combined with plastic film, aluminum foil) needs to be cut into finished rolls of specific width after the coating and composite process.
     Example: Composite paper for food packaging needs to be cut into widths suitable for bag making machines, with neat cuts and no dust pollution.
Challenges and Countermeasures of Cutting Tools:
     Adhesive coating easy to stick knife: using mirror polishing blade or coating technology (such as diamond-like carbon coating DLC) to reduce friction and adhesion between paper and blade.
     The difficulty of cutting composite layers is high: a round knife with a sharp edge and anti fatigue strength is required to avoid delamination of the composite layer during cutting.
2. Paper product slitting (such as paper tubes, paper cans)
Application scenarios:
      Paper tube production: Cut the roll of paper into narrow strips and roll them into industrial paper tubes (such as supporting cores for films and tapes) using a rolling machine.
      Paper can/paper cup production: The slitting circular knife cuts paper into specific sized fan-shaped or circular blanks for subsequent molding.
Tool features:
      High requirement for incision perpendicularity: Ensure that the seams are tight when rolling the paper strip and that the paper tube/can is not skewed.
      Impact resistance: When cutting thick cardboard or multi-layer composite paper, the cutting tool needs to have sufficient rigidity to avoid chipping.
3、 Waste paper processing and recycled papermaking
1. Sorting and cutting of waste paper
Application scenarios:
      After recycling waste paper, it is necessary to cut large pieces of waste paper (such as cardboard boxes and boards) into small pieces suitable for pulping machine processing to improve pulping efficiency.
Tool features:
      High strength structure: The round knife needs to withstand the impact of hard objects (such as iron nails and plastics) that may be mixed in the waste paper, and the material is mostly high chromium cast iron or alloy tool steel.
      Coarse tooth design: The blade can be designed in a serrated shape to enhance the tearing and cutting ability of thick waste paper.
2. Cutting of recycled paper
Application scenarios:
      Recycled paper is prone to edge damage during cutting due to its short fibers and low strength, requiring sharper cutting tools to reduce stress concentration.
Technical points:
      Use a small diameter circular knife to reduce cutting pressure, or use a vacuum suction device to fix the paper web and prevent paper displacement during cutting.

Related products