Cornwall-based Rigibore Ltd (www.rigibore.com) has introduced Nexus for the precise and consistent machining of large diameter bores (above 275mm).

This is a self-contained fine-boring unit that can be mounted to Wohlhaupter flanges; it contains a wireless transceiver, a battery and one of Rigibore’s innovative ActiveEdge cartridges.

This combination means that the insert can be adjusted for diameter either manually — using the ActiveEdge Remote control — or automatically if used in conjunction with Rigibore’s Zenith Industry 4.0-compliant automation system.

Suitable for both internal bores and overturning applications, with coarse and fine adjustment of the diameter down to one micron accuracy, Nexus eliminates the need to provide a tool for each individual bore.

The development of Nexus came about when Rigibore was approached by ZF Wind Power’s facility in Belgium, which makes gearboxes for wind turbines. These large high-value parts were subject to long set-up times due to restricted access when setting diameters.

Further complications arose from outside factors such as temperature variance, which meant constant checking and adjustment of bore sizes.

Rigibore developed a boring module that was compatible with existing boring flanges and could be integrated with its Zenith closed-loop tool compensation system and in-process gauging.

This combination delivered the control, accuracy and consistency that ZF Wind Power required, without the need for any manual intervention.

A major benefit for ZF Wind Power is the ability to use Rigibore’s “two-stage finish cut” system as part of the Nexus/Zenith system.

This sees the cutting edge automatically backed off to machine a pre-finish bore, which is measured.

This value is stored in the machine control and interrogated to determine the amount of adjustment required for the finish bore size to be nominal.

The specialised macros developed by Rigibore ensure that the Nexus tool is accurately adjusted to compensate — automatically — for insert wear, temperature change and material inconsistency.

The use of this technology at ZF Wind Power has seen a reduction in the scrap or reworking of large components, while cycle times have been greatly reduced due to the elimination of any manual intervention in the fine-boring process.