A servo motor-driven NC rotary table with a very large through-hole has been introduced by Kitagawa to facilitate accurate milling and drilling of tube- and shaft-type components on machining centres and manual mills. The competitively priced unit, designated TG530, is available in the UK from 1st MTA, Salisbury.

The 345 mm diameter hole through the centre has been sized to accept pipe up to 13⅜ inches (340 mm), which is a standard used in the oil and gas industry for such applications as borehole casing.

The mechanical structure of the TG530 is designed to withstand the heavy cutting torques (up to 2,600 Nm) required to machine tough materials used for some aerospace components. Hydraulic clamping torque is exceptionally high at 6,100 Nm to allow heavy static machining.

Of rigid build for top machining accuracy, the unit weighs 366 kg, one third less than the equivalent model in Kitagawa TR table series, which has a through-hole only half as large.  Lower rotary table weight means that heavier components can be machined without exceeding the maximum table load of the machine tool.

Centre height is 310 mm, maximum rotational speed is 11.1 rev/min using a gear reduction ratio of 1/180, and indexing accuracy and repeatability are 20 and 4 seconds of arc respectively.  The unit can be mounted vertically or horizontally, maximum permissible component weight being 350 and 700 kg respectively.