Over the last 18 months, Brighouse-based Asquith Butler Ltd (
www.asquithbutler.com) — a long-established British machine tool manufacturer synonymous with its range of large-capacity, travelling-gantry (vertical) and travelling-column (horizontal) machining centres — has become the exclusive UK distributor for a range of machining centres from three European manufacturers: Zayer, Sahos and Mubea Systems.
The agreements cover machine sales, installation, commissioning and service support, and Asquith Butler has already sold a number of these machines into the UK market.
The Spanish firm Zayer has been particularly successful across Europe and in its home market in recent months. For example, it has sold two large five-axis machines for tool making, one to Audi Tooling Barcelona and another to Batz.
Located near Bilbao, the latter manufactures stamping tools for vehicle component production and supplies JLR, BMW and Volvo, as well as other famous marques.
Paul Hinchliffe, managing director of Asquith Butler, sees considerable potential for these machines in the UK, especially in the automotive sector.
Acceptance of the Zayer Tebas 6000 by Audi Tooling Barcelona was completed in April 2014. The machine has gone into the firm’s 4,000m2 Tryout Center in Martorell, which was opened in March 2014 and makes die sets for producing car body parts. These die sets are tested extensively on one of three 2,500-tonne try-out presses before delivery to customers.
The five-axis Tebas 6000, which offers a very high volumetric accuracy, has two universal automatic milling heads that can be orientated in 360,000 positions. One is a 45deg mechanical head powered by a 45kW German-made Kessler motor offering spindle speeds up to 6,000rev/min; the other is a 30deg head with a 23kW 24,000rev/min electro-spindle for fine finishing cycles.
The fully enclosed machine has a 6,200 x 2,500mm table and a distance between columns of 3,500mm. Travels in X, Y and Z are 6,000, 4,250 and 1,500mm respectively. Cameras are positioned under the cross-beam, and there are probes for tool measurement and for use with Zayer’s proprietary ICAL system for automatically calibrating the milling heads.
Control is by a Heidenhain iTNC 530 HSCI contouring CNC system with all-digital interfaces. Furthermore, the machine features a polymer concrete bed that is mounted on springs to prevent vibrations affecting the surface finish
of the dies.
High-speed finishing
Founded in 1963, Batz is part of Mondragon, the largest co-operative industrial group in the world. Batz’s headquarters are in Igorre (20km from Bilbao). and 1,500 people are employed in more than 15 facilities world-wide.
Batz has been producing stamping dies from the outset. However, in 1982 the company established an automotive systems division for the series production of vehicle components. More recently, it has focused on new and lightweight materials, particularly for the aerospace industry; renewable energy is another area of activity.
For Batz’s core business of stamping-die manufacture, capacity issues meant that a dedicated machining centre was needed to finish large dies, hence the recent installation of a Zayer Memphis 7000 high-speed five-axis
machining centre.
The longitudinal travel is 7,000mm, the distance between columns is 5,000mm, and dies are fixtured on a 6,500 x 4,000mm table that can support 15 tonnes per sq m. High levels of productivity are ensured by cutting-feed rates up to 20m/min and 40m/min rapids.
The gantry-type machine was supplied with four spindle heads that can be automatically exchanged. One head is rated at 43kW 6,000 rev/min; there is also a 30deg head of the same rating offering 360,000 positions in 0.001deg
increments.
An extended L-shaped 12kW head is for machining awkward areas within dies at up to 2,000rev/min, while the fourth head carries a 23kW electro-spindle capable of finish-milling at speeds up to 18,000rev/min.