Designed to reduce set-up times on lathes, the new BR-series three-jaw chucks from Japanese firm Kitagawa offer a gripping accuracy of 0.01mm TIR (total indicator reading) — or less when using optional T-Nuts Plus jaws. The repeatability of jaw exchange is within the same tolerance, even on the largest chuck.
The chucks are made in 6, 8, 10 and 12in versions, and they are available in the UK and Ireland through the Salisbury-based sole agent 1st Machine Tool Accessories (
www.1mta.com/product/br-series).
The BR-series chucks — now Kitagawa’s standard offering — are interchangeable with the company’s B-series chucks and its large through-hole BB-series chucks, which are both superseded (their TIR could only be guaranteed within 0.02mm).
Due to a new design of base jaw and lower jaw lift, gripping forces at the maximum rotational speed of the chucks have been increased by 10-15% to enable better metal removal rates. High spindle speeds have been maintained throughout the range to enhance the surface finish of turned components.
On twin-spindle chuckers, which are becoming ever more prevalent in turning shops, the better rotational accuracy of the workpiece allows more-precise synchronous transfer from the main spindle to the counter-spindle for second-operation machining.
The gripping force is up to 153kN for the 12in chuck, while the maximum rotational speed attainable on the 6in model is 6,000rev/min. Every chuck includes a QR code on the side to allow data on the product to be downloaded.