Cutting-tool and tooling-system specialist Sandvik Coromant has introduced a new collet for its CoroChuck 930 high-precision hydraulic chuck.
Designed to suit Weldon shanks, the new collet features a mechanical locking interface to prevent tool pull-out or movement when machining with ‘challenging cutting data’.
Mats Backman, global product manager at Sandvik Coromant, said: “Being 100% assured of zero pull-out for Weldon shanks when producing high-value-added parts is paramount in the highly competitive manu-facturing arena.
Production engineers being under constant pressure to minimise scrap and maximise profitability was the driver for developing the new collet.”
The mechanical locking interface acts between the collet and the chuck, and between the collet and the shank; pull-out effectively changes the gauge length of the tool mid-cut, leading to the generation of features with incorrect dimensions or crash marks.
Having confidence in ‘no pull-out’ when both collet and chuck are locked enables increased productivity in heavy-duty applications.
Further benefits include easy assembly into Coro-Chuck 930 chucks (both slender and HD versions), while high run-out accuracy is assured with cylindrical clamping of Weldon shanks.
In addition, coolant supply through the collet ‘provides secure and reliable coolant delivery to the tool’.
One example of the potential gains on offer is a customer trial that saw a CoroChuck 930 (featuring the new collet) used for a milling operation on a CNC turn-mill machine.
The objective was to produce a twin-screw from 42CrMo4 alloy steel.
Cutting with a 3,220rev/min spindle speed, 1,500mm/min feed, 10mm axial depth of cut (nominal) and 20mm radial depth of cut, the mechanical locking interface provided a stable process with no pull-out — and productivity increased due to longer tool life.
Further details can be found at the Web site (
www.sandvik.coromant.com/en-gb/products/corochuck_930/page/default.aspx).