The HS 630sp combines large capacity with speed and accuracy

Citation

(2002), "The HS 630sp combines large capacity with speed and accuracy", Aircraft Engineering and Aerospace Technology, Vol. 74 No. 6. https://doi.org/10.1108/aeat.2002.12774fab.003

The HS 630sp combines large capacity with speed and accuracy

The HS 630sp combines large capacity with speed and accuracy

Keywords: Machining, Productivity, Cost

With rapid traverse speeds and maximum feed rates of 50 m/min, double the previous HG generation of large capacity machining centres, Hitachi Seikils latest HS 630sp horizontal machining centre is said to be able to considerably reduce machining times while maintaining very high levels of accuracy (Plate 3).

The high precision machining centre has, in its basic 630 mm square twin-pallet format, a working envelope of 1,000 mm in X by 850 mm in Y and Z. These machine capacities allow large workpieces or bulky fixtures to be accommodated with ease, up to maximum table load of 1.2 tonnes.

Developed primarily for machining large, single or multiple fixtured aluminium or aerospace type components, the HS 630sp has a 12,000 revs/min spindle and programmable feed rate up to 50 m/min.

Plate 3 Hitachi Seiki HS 630sp horizontal machining centre combines speed with accuracy in a large volume production unit

In addition, the optional software packages developed by Hitachi Seiki for high speed machining, SHG-1 for high speed machining and SHG-2 for mould machining, reportedly ensures shorter cutting cycles and increased productivity.

The machine includes Hitachi Seiki’s Artificial Intelligence Thermal Accuracy Control Software ATAC 10. This inbuilt thermal compensation system is said to operate from cold start to continuous running to ensure accuracy and stability within ± 10 microns of nominal in Y and Z axes. Accuracy is enhanced by the integration of a spindle cooling unit into the standard specification and can be further enhanced with the availability of optional linear scale axis feedback positioning.

Additional optional facilities include 70 bar through spindle coolant and a 12,000 revs/min high speed 30 kW, BT 50 taper spindle which equips the machine for a wide variety of tasks.

The latest built-in motor technology is used which typifies the machine specification to supply rapid spindle acceleration from zero to maximum speed within 1.6 s. Fast spindle acceleration is coupled with total freedom from motor induced vibration. Tool capacity is 41 units held in chain-type magazine with options for up to 330 tools.

The high speed machining software package SHG-1 provides a series of special cycles with on-screen graphic guidance. These enable features to be produced using high speed side milling with low side loading on the tool and increased depth of cut and a special Z-feed grooving cycle to create cutting conditions that are claimed to be up to 10 times faster than normal cycles. Also incorporated are high speed corner and square pocketing cycles, a trochoid cycle for producing circular or wider width grooves using an endmill in a circular motion and a helical boring cycle for producing taper holes and taper threads.

The SHG-2 mould machining option transforms the HS 630sp into a mould machining centre using microblock programs with in-built 64 bit RISC processing. This enables four modes of operation to be selected covering high speed, standard, higher accuracy and user configurable cycles.

Guideway service life is maximised due to the application of Hitachi Seiki’s Eco-eco system which eliminates the need for slide or ballscrew lubrication. Because there is no “total loss” of lubrication oil on the machine, tramp oil contamination of coolant is eliminated. This feature is thought to increase coolant life by up to 500 per cent and considerably reduce overhead running costs and disposal problems.

The HS 630sp is believed to be equally suitable for stand-alone production or for incorporation into a multi-machine cell for extended periods of unmanned running. With that in mind, various options may be specified to assist minimally manned or more consistent production working including automatic tool breakage detection, cutter monitoring/tool management and on-machine measuring.

Details available from: Hitachi Seiki UK Ltd, Tel: +44 (0) 1784 433711; Fax: +44 (0) 1784 437691; Web site: www.hitachiseiki.co.uk