The new TKM eKnife for book binding machines, tailored with the focus on sustainability, innovation and technology.

The TKM Group

The TKM Group is one of the leading suppliers of industrial machine knives and cutting solutions for the paper, wood, metal, plastics, rubber and recycling industries. With 750 employees and 12 individual companies, the family-owned company is generating an annual turnover of around EUR 147 million. The first-class products are serviced in more than 100 countries around the world.

In an R&D project and which was lasting over a couple of years, TKM investigated the question of how to make a knife for the book production not only more innovative, but also more sustainable.

State of the art and the today’s technology:

The cutting tools and which are currently available on the market are typically produced in carbide (TCT) and steel grades. The higher alloyed inlay material is either brazed or bonded / glued to the body material. Both methods, which are also used by TKM, have advantages and disadvantages. Brazing achieves a much higher tensile strength, compared to the bonding technology, but the straightening process is more intensive in the production. In terms of cost, the two joining techniques are comparable.?

The knives for the three-knife trimmer are joined to the said body material made of? standard steel with a 20-30 mm high-alloyed insert (carbide or steel). These knives typically have 4-6 kg per knife in weight and can be sharpened 20 times or more, which depends on the cutting application and wear. Each re-sharpening process removes approximately 0.5 to 1 mm of knife width. After the last resharpening interval, the knife must be replaced with a new one. Suitable or even single variety recycling concepts are not yet available on the market.

Industrial cutting tools and their CO2 impact

As a general rule, it can be said, that the industrial steel production emits approximately 1.5 to 2 tons of carbon dioxide for every ton of steel produced (this figure varies depending on the choice of the material). This equates to around 10% of global CO2 emissions. In other words, up to 12kg of harmful greenhouse gases are emitted to replace a 6kg knife. While most steel companies have made a commitment to significantly reduce CO2 emissions by 2050, they are currently far from this "green" steel. In addition to emissions from steel production, other greenhouse gases are generated during the production of knives.

Furthermore, users in areas where a high-quality grinding service is not available or only available to a limited extent (in addition to the grinding machines, straightening devices are required as well), are often unable to use cutting tools for their optimized service life. As a result, cutting tools are used that wear out more quickly and must be ground more frequently. Simple knife qualities are used, and which are chosen to the possibilities of the level of service only. Health and safety is also a key consideration. Every knife which is not changed will increase the safety in operation and reduces the risk of injures and accidents related to knife handlings.?

In most cases, the regrinding service is sourced out to a regional service partner. This company is specialized into collecting blunt knives and delivering sharp tools. These companies drive several 100,000 km per year and are creating a high value of Co2 emission. Just as an example, service vans with a loading capacity between 3.5 to 7.5 tons caused 2022 in Germany a Co2 emissions of more than 569 grams per ton-kilometer ?(statistics taken from the German Federal Environment Agency).

The invention

The new TKM eKnife addresses exactly these issues. Why not use an insert tailored to the material to be cut?? Why not use a body that can be used multiple times and unlimited? In this case, the knife wear is limited to the insert only. This not only reduces knife changing costs, but also sustainably reduces greenhouse gas emissions. This is more efficient, but also much better for a greener environment and minimizes costs at the same time. Further positive effects can be achieved through innovative and smarter grinding techniques.

TKM has taken this challenge and carefully analyzed, digitized and documented previous attempts and experiences. This led into the conclusion, that there is a solution which is not only sustainable but also progressive and innovative. The goals (function and cost-effectiveness) were redefined in the specifications, with the aim of offering such product to a wide market.

With a weight saving of almost 90% compared to conventional knives, emissions can be greatly reduced in future without having to accept any loss in cutting quality and life time.