Among the principal differences in the latest-generation tool is the change of boring head material, from steel to aluminium. In addition, the head has been shortened so that the damper comes closer to the cutting edge, which is beneficial for process stability.
“Internal channels are utilised to deliver coolant directly to the cutting edge, which is another factor that contributes to improved surface finish, higher penetration rates and greater process security,” says Jenny Nilsson, global product manager at Sandvik Coromant. “This new generation of tools will provide optimum performance and stability with one standard adaptive item on the machine-tool side – to bridge the tool into a steep taper, HSK or Coromant Capto spindle. Further extensions will reduce stability and performance.”
The CoroTurn insert carriers for the new tools have entering angles at 92-95°. This design increases stability due to reduced tool assembly deflection, making it possible to approach the bottom of a blind hole without engaging a bigger part of the cutting edge.
CoroBore 825 is suitable for all fine-boring applications, covering diameters from 19 to 167 mm, while a new assortment of cartridges can be utilised for back-boring applications. During back boring, the same internal coolant flow to the cutting edge is offered as with conventional boring.
For ease, the complete tool, comprising adaptor and insert carrier, is delivered as a kit using a single product code.