The Australian Government has ordered the construction of a fleet of 12 regionally superior submarines, known as the Attack Class, for its Royal Australian Navy.
As part of the construction effort, which will last until the 2050s, the Future Submarine Program construction process will also provide Australian industry the means to build, operate and maintain the fleet at a submarine construction yard in Osborne, South Australia.
Because the program is a mult-decades long, the equipment must be robust and built for the long term. One critical piece of technology that met this criteria is a 5-axis gantry machine from Switzerland-based The Starrag Group.
Described as Australia’s largest machine tool, Starrag is supplying a Droop+Rein G 110TT HR100 C vertical gantry machine that is capable of handling both large hull elements and high-precision components for submarine construction. This large production machine features traversing paths of 45.93 x 42.65 x 11.48 ft (14,000 x 13,000 x 3,500 mm) in the X/Y/Z axes and an 36 ft (11 m) turntable.
Starrag is collaborating with the Australian machine tool manufacturer H&H Machine Tools Australia. H&H will manufacture key components, supply qualified personnel to help install the gantry and provide technical support for the entire life cycle of the machine, securing an ongoing role in servicing and maintenance in the future. Starrag will provide H&H with the necessary expertise through onsite training and quality control, transferring critical skills and autonomous ability to Australian industry.
According to Dr. Marcus Queins, manager for the large parts machining systems business unit at Starrag, the size and efficiency of the milling machine being supplied was of fundamental importance. The unit, which is also capable of turning components thanks to an integrated rotary table, is a “tried and tested” unit that is part of the Dörries range of lathes from the Starrag Group, he said.
According to the company, the Droop+Rein G 110 TT HR100 C owes its high precision to features such as the hydrostatic guides in all linear axes, as well as the thermo-symmetrical design of the milling unit with its integrated C axis. Milling heads can be changed automatically via a head change interface. Five different machining heads were selected to use on this project. The high-performance fork milling head features not only the ability to use the tool at any angle, but also the necessary prerequisites for heavy-duty machining on five axes simultaneously. Alternatively, the machine can be used with one straight and one angled 134HP (100-kW) milling head with a torque of 5531 ft-lb (7,500 Nm). A turret and a horizontal facing head are available for turning operations on the components.
The large, multifunctional machine supplied by Starrag from its Bielefeld, Germany, plant gives the operator optimum access. According to Starrag, the operator can reach any point on the workpiece thanks to the spacious cabin, which travels along the gantry and features a Siemens operator panel. The cabin can reach a height of 26ft (8m) and be moved towards the center of the table.
The gantry's robustness was a factor in its selection. Starrag was able to support this from the success of a previous project carried out in South Australia, for which Starrag supplied four machines for aircraft construction. The company believes that with proper maintenance, the machine will be operational throughout the entire run of the project. The first of the Attack Class submarines will be delivered in the early 2030’s and continue into the early 2050’s.
Starrag Group is a global technology leader in manufacturing high-precision machine tools for milling, turning, boring and grinding workpieces of metallic, composite and ceramic materials. Its North American headquarters can be reached at 859-534-5201 or visit them at www.starrag.com.
Related Glossary Terms
Enlarging a hole that already has been drilled or cored. Generally, it is an operation of truing the previously drilled hole with a single-point, lathe-type tool. Boring is essentially internal turning, in that usually a single-point cutting tool forms the internal shape. Some tools are available with two cutting edges to balance cutting forces.
- gang cutting ( milling)
gang cutting ( milling)
Machining with several cutters mounted on a single arbor, generally for simultaneous cutting.
Machining operation in which material is removed from the workpiece by a powered abrasive wheel, stone, belt, paste, sheet, compound, slurry, etc. Takes various forms: surface grinding (creates flat and/or squared surfaces); cylindrical grinding (for external cylindrical and tapered shapes, fillets, undercuts, etc.); centerless grinding; chamfering; thread and form grinding; tool and cutter grinding; offhand grinding; lapping and polishing (grinding with extremely fine grits to create ultrasmooth surfaces); honing; and disc grinding.
Machining operation in which metal or other material is removed by applying power to a rotating cutter. In vertical milling, the cutting tool is mounted vertically on the spindle. In horizontal milling, the cutting tool is mounted horizontally, either directly on the spindle or on an arbor. Horizontal milling is further broken down into conventional milling, where the cutter rotates opposite the direction of feed, or “up” into the workpiece; and climb milling, where the cutter rotates in the direction of feed, or “down” into the workpiece. Milling operations include plane or surface milling, endmilling, facemilling, angle milling, form milling and profiling.
- milling machine ( mill)
milling machine ( mill)
Runs endmills and arbor-mounted milling cutters. Features include a head with a spindle that drives the cutters; a column, knee and table that provide motion in the three Cartesian axes; and a base that supports the components and houses the cutting-fluid pump and reservoir. The work is mounted on the table and fed into the rotating cutter or endmill to accomplish the milling steps; vertical milling machines also feed endmills into the work by means of a spindle-mounted quill. Models range from small manual machines to big bed-type and duplex mills. All take one of three basic forms: vertical, horizontal or convertible horizontal/vertical. Vertical machines may be knee-type (the table is mounted on a knee that can be elevated) or bed-type (the table is securely supported and only moves horizontally). In general, horizontal machines are bigger and more powerful, while vertical machines are lighter but more versatile and easier to set up and operate.
- quality assurance ( quality control)
quality assurance ( quality control)
Terms denoting a formal program for monitoring product quality. The denotations are the same, but QC typically connotes a more traditional postmachining inspection system, while QA implies a more comprehensive approach, with emphasis on “total quality,” broad quality principles, statistical process control and other statistical methods.
Workpiece is held in a chuck, mounted on a face plate or secured between centers and rotated while a cutting tool, normally a single-point tool, is fed into it along its periphery or across its end or face. Takes the form of straight turning (cutting along the periphery of the workpiece); taper turning (creating a taper); step turning (turning different-size diameters on the same work); chamfering (beveling an edge or shoulder); facing (cutting on an end); turning threads (usually external but can be internal); roughing (high-volume metal removal); and finishing (final light cuts). Performed on lathes, turning centers, chucking machines, automatic screw machines and similar machines.