During strand pelletizing of fiber-reinforced plastics, highly abrasive polymer strands place extreme mechanical and tribological stress on the bed knife and its cutting edge. MAAG has addressed this issue with the Duration cutting blade, developed specifically for FRP applications in its strand pelletizers and granulators. The blade is intended for production environments where fiber-filled and high-strength compounds rapidly degrade conventional cutting edges, leading to frequent tool changes, process interruptions and variability in pellet quality.
Until now, cutting blades for MAAG strand pelletizers have been supplied in three designs: tungsten carbide, abbreviated HM, ceramic, abbreviated CE, or with a diamond-coated surface, abbreviated PCD. In FRP processing, each option combines specific advantages with notable limitations. In particular, the cutting edges of HM and CE blades typically reach only about 100 operating hours due to the high abrasiveness of fiber-reinforced materials. Ceramic blades are also susceptible to fracture, which can necessitate early replacement of the cutting edge or the entire blade. Such interventions affect line productivity as well as the consistency of the pellets produced. For this reason, diamond-tipped PCD blades are often selected for FRP jobs, since their hard surface markedly prolongs service life. However, PCD solutions can be up to five times more expensive than carbide or cemented carbide tools, which impacts operating costs.
Newly developed material: longer service life at an affordable price
MAAG has expanded its offering with a new cutting edge that uses a material designated VS23. According to the company, VS23 increases surface hardness by up to 70 percent versus conventional carbide, reducing the wear rate under abrasive FRP conditions. In practice, this translates into a service life extension by a factor of 5 to 9 compared with standard carbide tools. The Duration blade is configured with four cutting edges, providing an additional cost advantage relative to PCD blades that carry diamond segments on only one edge. The performance of the new blade design has been validated in both laboratory testing and production use.
