Rigibore says that an engine manufacturer has gained total control over its boring processes thanks to the introduction of the company’s automated boring tool compensation system, Zenith.

The system was selected for its ability to make compensations automatically from measurement data to an accuracy of 1 µm on diameter. Maintaining much closer machining tolerances on crankshaft bearing journals not only enhances the quality of the finished component, but has a direct impact on engine efficiency and emissions.
The concept was to produce line boring bars with five semi-finish cartridges set 0.1 mm below nominal, thus allowing five ActiveEdge finish cartridges to machine all journals in a single pass. ActiveEdge line bars were automatically compensated to nominal from data provided by offline gauging that was transferred to the machine control as part of the Zenith closed-loop system.
Before installing ActiveEdge tools, the customer carried out verification checks to confirm that each cartridge could be adjusted independently in increments of 0.001 mm on diameter. With this ability confirmed, an extended live cutting trial was instigated. The trial took place on a twin-spindle machining centre, with each spindle machining 946 crankshaft bores over a 24-hour period, so 1892 in total. In this time, not a single bore was out of tolerance thanks to ActiveEdge’s intervention. The finished bores had a mean diameter of 52.965 mm with a tolerance of ±0.015 mm. During the test period, bore sizes were maintained within a variance of just 2 µm.
Prior to installing the tooling, the process of ensuring nominal size before the production run took 45 minutes on average. In contrast, Zenith allows automatic, individual cutting edge compensations to be made with the tool located anywhere in the machine, completing the setting process after an insert change within a matter of minutes.
For further information www.rigibore.com

Expanding the series of solid-carbide end mills and slot drills defined by Sumitomo Electric Hardmetal as its “global standard”, the GSX Mill series is now available. The latest milling cutters have been developed based on a fine carbide substrate to increase toughness.

GSX Mill tools also have a high transverse rupture strength and provide high levels of shock resistance with enhanced orders of consistency and reliability, especially in wet cutting conditions.
The GSX Mill series, covering tools between 1 and 25 mm diameter, has a special flute design and large rake angle. The cutters come in many varieties, covering two, three and four-flute types, in four different lengths of flute. A novel combination of flute design and rake angle enables effective chip evacuation from the cutting zone, while the specific design of two cutting edges improves sharpness and extends the type of workpiece that can be machined.
Typical end mill and slot drill applications cover surface milling, drilling and grooving, with two types of cutting edge profiles. The sharper edged S-Type is suitable for removing inside corners when finish-cutting, while the strengthened edge C-Type, having a gashed land, creates higher resistance to fracture for both roughing and finishing cycles.
The GSX-SLT slot-type cutter is a multi-purpose tool developed for plunge drilling and slot milling, having a large rake angle for efficient chip removal. Also within the GSX Mill series is the GSXVL, which is an anti-vibration, square-type cutter for shoulder milling with an optimised irregular pitch and lead angle that improves resistance to chatter.
Finally, the Sumitomo GSXB Mill ball-type cutter has two flutes and a large 30° helix angle that reduces any resistance to cutting forces, so is suitable for milling hardened steel up to 60 HRc, titanium alloys and cast iron.
For further information www.sumitomotool.com