Cutting quality & dust (circular knives)

Why must you frequently change your slitter knives? How can you optimize the cutting quality and reduce dust?

• Wrong knife adjustment (adjustment between top and bottom knife, knife overlap, side pressure, cant angle)
• Slitter jumps (top knife damages the bottom knife)
• Wrong choice of knife quality (top to bottom knife)
• Knife chips and breakouts
• Knife geometry and tolerances are not in line with the OEM requirement and guideline
• Grinding errors and mistakes
• Paper dust 

Constantly improve the cutting quality and reduce paper dust

The cutting quality is strongly influenced to the right use (set-up) and knife’s material combination. Additionally, geometric parameters and the adjustment of the knives must be taken into account. In most of the cases, bottom knives run with an 5 % overspeed to the paper web and therefore top knives. The bottom knife should have max. the same hardness (measured in HRC - Rockwell) as the top knife. If otherwise used, the bottom knife will wear too fast and has a direct impact to the life time and cutting quality of the knives.

As better the surfaces are polished (standard 400µm vs. polished < 100 µm) and as tighter the tolerances are defined (radial runout up to 30µm), as higher cutting qualities will be achieved and with a lower paper dust impact. Other parameters are the knife angles (sharp vs. blunt) and a professional honing / de-burring of the knife surface after the grinding process.

Slitter jumps are mainly seen because of a wrong set-up procedure and a too low overlap.

We recommend:

TKM slitter knife sets consisting out of top and bottom knives, which are produced with narrow tolerances and polished surfaces. All TKM knives fit to your individual cutting application. Ask our service specialists for the best set-up procedures and the most cost-effective cutting solutions. Book our best practice “slitter training courses”, this will optimize your cutting processes.