Five-axis mill-turn capacity extended

Part of the British Engines Group based in the north of England, BEL Engineering operates two factories at Newcastle-upon-Tyne and Cramlington to provide project-managed manufacturing solutions, some of which involve the heavy-duty subcontract machining of large workpieces weighing up to 40 tonnes.

Much of the metal-cutting activity involves turning on horizontal- and vertical-spindle lathes, but parts often have to be transferred to a prismatic machining platform for milled and drilled features. Around 30 three-axis CNC mills are available at BEL for this purpose. However, for such parts to be produced more economically in one clamping, the subcontractor recently invested in a Hermle C62 UMT five-axis, vertical-spindle machining centre supplied by Kingsbury.

Having a nominal 1 cubic metre working envelope, the machine was duly installed at the Newcastle factory. It was BEL Engineering’s second venture into this technology; an Italian-built, five-axis mill-turn centre with travels in excess of 2 m in X, Y and Z having been installed a few years earlier. There is also a pair of Japanese-built five-axis CNC milling centres on site, one with a 10-pallet storage system.

The Hermle fits neatly between these larger and smaller five-axis models, extending the subcontractor’s capacity. In particular, following the company’s accreditation in October 2019 to AS9100, the machine is proving to be of ideal size to produce aero-engine parts for a nearby customer.

Bel Engineering’s chief production engineer Phil Westgarth says: “We mainly process tough materials, from high-strength steels through titanium, to nickel superalloys like Hastelloy, Waspaloy and Inconel. So we need powerful, rigid machine tools. A pair of similar Hermle mill-turn centres is being used successfully at another of our group companies, Michell Bearings, so this influenced our choice of the German machine.”

For further information www.kingsburyuk.com

Laser texturing of large moulds

A new gantry-type, five-axis CNC machine for laser texturing the 3D freeform surfaces of moulds and tools weighing up to 20 tonnes – and with maximum dimensions of 3350 x 1350 x 1000 mm – has been introduced by DMG Mori.

The Lasertec 400 Shape is the largest model in a range of four laser ablation machines, the others being designated 45, 75 and 125. A further machine version is planned with a 2000 mm X axis, the Lasertec 200 Shape.
It is becoming increasingly important in many industries, especially the automotive and aerospace sectors, to impart geometrically defined surface structures to plastic injection moulds and press tools to improve the aesthetics and functional properties (such as scratch resistance and water repellence) of components.
The machining of textures is more environmentally-friendly than conventional etching and offers considerable freedom of design, while at the same time ensuring a high level of repeatability. This process is also capable of creating filigree cavities without the need to manufacture electrodes.
DMG Mori’s Lasertec 400 Shape is equipped with a newly developed additive manufacturing laser head that is both narrow and compact. Excellent accessibility is available to a component, even if it has deep and slender features, eliminating the need for long focal lengths that would slow the ablation process.
Central to machine operation are a 100 W fibre laser with switchable pulse length and frequency up to 1 kHz, and 3D processing optics with F-Theta scanning lens. The two degrees of movement of the head are ±200° of rotation and a swivel range of -100° to +135°, enabling undercuts to be processed.
For further information www.dmgmori.com

Simultaneous launch by Mills CNC

Mills CNC, the exclusive distributor of Doosan machine tools in the UK and Ireland, has introduced two Doosan five-axis machining centres.

The two machines – the DVF 6500 (650 mm diameter table) and the larger capacity DVF 8000 (800 mm diameter table) – are from the same stable as the Doosan DVF 5000 machine that was launched 18 months ago.
Both machines are compact and have a rigid structure for increased accuracy, improved surface finish and greater process reliability. The new models boast 45 m/min rapid traverse rates and are equipped with oil-cooled, directly-driven BT40 spindles (up to 22 kW/18,000 rpm) to suit 3+2, 4+1 or full five-axis simultaneous machining.
Also featured are servo-driven automatic tool changers (up to 120 tools) with a 1.3 second changeover time, roller LM guideways and direct-drive rotary tilting tables (A axis = +120/-120°; C axis = 360°).
The DVF 6500 and DVF 8000 machines are available with a choice of control (Fanuc 31iB5, Heidenhain TNC640 or Siemens 840D with ShopMill software), and are supplied with thermal compensation systems and a long-life, grease lubrication system. A collision protection system can also be offered
as an option.
There are some differences, however. The DVF 6500 and DVF 8000 have different-sized travels (DVF 6500 = 750 x 785 x 600 mm; DVF 8000 = 1000 x 900 x 685 mm) and different table loads (up to 1000 and 1400 kg respectively).
Within the DVF 8000 range a specific ‘Turning’ model can also be specified. The DVF 8000T, with its integrated function, has the same technical specification as the DVF 8000 in most respects, except for a lighter maximum table load (700 kg) and a faster C-axis feed rate (600 rpm).
For further information www.millscnc.co.uk

The art of micro-machining

The micro-machining capabilities offered by a Bumotec machining centre have recently been demonstrated by AMRC engineers who used the Swiss-made mill-turn machine to reproduce a series of tiny brass portraits of Queen Elizabeth II.

Indeed, the intricate detail of Her Majesty’s head can only be seen clearly through a powerful microscope.
It is a major achievement for University of Sheffield AMRC engineers Emma Parkin and Joe Thickett, who wanted to create the miniature artwork to demonstrate the AMRC Machining Group’s capabilities with the goal of bolstering industry knowledge on micro-machining to help UK firms win business.
Supplied by Starrag UK, the Bumotec s191 – one of eight Starrag machines in-situ at the AMRC and its sister centre, the Nuclear AMRC – was used by Parkin and Thickett to produce four highly-detailed Queen’s heads with diameters of 11.2, 7, 2.8 and 1.4 mm, on a single circular piece of 25 mm diameter brass. The pair used Sandvik micro-end-mills to achieve the basic shape of the design before switching to tiny ball-nose cutters – the smallest of which was just 0.2 mm diameter – for detailed contouring.
“We wanted to show our partners and wider industry what is achievable; that we can work to an accuracy of 0.001 mm on workpieces as small as 1.5 mm, and maintain detail,” says Parkin.
She is hoping the ‘coin’ demonstrator will lead to further micro-machining R&D and commercial projects for the AMRC.
“At the moment, when people come to the AMRC, and here to Factory of the Future, what they generally see are massive aerospace components and huge machines. I want people to also say ‘wow, the AMRC can make some really small parts, let’s work with them’.”
For further information www.starrag.com

Correa opts for Redex technology

Two recently introduced milling machines from Nicolás Correa are leveraging the benefits of the latest-generation rack and pinion drives technology from Redex.

The company says that choosing the Redex drivetrain was the way to enable superior dynamic performance for users of the new Fox-M gantry-type CNC milling machine, and the Fenix travelling-column CNC mill.
One of the main differentiators with Correa Fox-M milling machines is the head technology. For instance, the company´s UAD universal and OAD orthogonal indexing milling heads are said to be unique in the market, with patented technology allowing rotation every 0.02°, while the Correa two-axis ´twist-type´ contouring head can be supplied to those seeking five-axis machining solutions. This head type features a high-performance electro-spindle or a spindle geared transmission.
Typical applications for the Fox-M include construction machinery components, railway parts, machine-tool components and wind energy frames.
The Fenix is another recent addition to the Nicolás Correa portfolio. Introducing a new concept of travelling-column machine, the Fenix is based on a system of L-guided RAM technology, which is precision-enabled through a mechanical system of RAM droop correction.
A common denominator between the Fox-M and Fenix machines is that they both leverage the benefits of the latest Redex planetary drive-train technology in the rack and pinion X-axis drive. This development is an example of how Redex continues to centre its efforts in challenging areas, for instance by focusing on planetary gear trains to reduce vibration, noise and transmission errors.
Moving forward, Redex gearbox solutions will be at the heart of many future machine-tool developments from Nicolás Correa.
For further information www.redex-andantex.com