Product category:
CNC turning centres, mill/turning, multi-tasking centres, horizontal and VTLs.
News Release from: Geo Kingsbury Machine Tools | Subject: Index SpeedLine C-type bar automatics
Edited by the Manufacturingtalk Editorial
Team on 11 February 2008
Mill-turn centres increase metal removal
rate
German CNC lathe builder has redesigned its mill-turn centres that are over twice as rigid as earlier models, allowing an increased depth of cut to be taken to maximise metal removal rate.
Index Werke, Germany, said that the higher the resonant frequency (RF) of a machine tool's structure, the greater is its inherent stiffness and the more difficult it is for machining forces to induce vibration Consequently, the company has redesigned its patented SpeedLine C-type mill-turning centres to increase their RF above that of all other lathes on the market, including existing models in its own range
This article was originally published on Manufacturingtalk on 26 Aug 2003 at 8.00am (UK)
Related stories
Foundry's mill-turning investment ups exports
Coventry-based foundry has upheld and expanded exports by adding on high-tech mill-turning centre facilities to machine turbocharger impellers supplied to Italian and US customers.
Pick-up spindle lathe has hexapod features
A new, hanging-spindle, vertical turning lathe (VTL) has been introduced by Index on which the spindle head is able to move freely in three dimensional space.
Using the RF measure, the new C-type lathes are over twice as stiff, or rigid, as the established Index G-series models of equivalent capacity.
Index said that there is more latitude for finding the 'sweet spot' for any combination of toolholder, cutter and workpiece material, allowing depth of cut to be increased for maximum metal removal rate.
Apart from increasing productivity, high rigidity and the lowering of machine tool vibration also ensure good surface finish of the machined part, said Index.
Further reading
Vertical turning lathe takes on complex production
New from Index is the option to fit a four-axis CNC tool turret in addition to a standard two-axis turret on the German manufacturer's V300 vertical turning lathe (VTL), allowing the production of mor
Brass turning on CNC lathes
Leipold (UK) uses eight Index 6-axis CNC lathes supplied by Geo Kingsbury, the latest two installed during May and June 2000
Bigger envelope vertical-spindle machining centre
The new, Spanish-built Kondia ZM-99 vertical-spindle machining centre from Geo Kingsbury MHP has a working envelope more than 50 per cent larger than the CM60-MA model which it replaces.
Also tool life is prolonged and noise reduced.
Better damping leads to higher accuracy machining, even for strenuous applications involving intermittent hard turning and reaming, said the company.
The SpeedLine C-type 42mm and 65mm bar automatics, when launched in 2005, were the first in the world to replace conventional compound turret slides with two interconnected steel plates sliding directly over the machine bed.
The recent redesign of the range has seen these machines improved and two new models introduced with 30mm and 90mm bar capacities.
* Lathe build time reduced - at the same time, Index has reorganised C-type flow line assembly at its Esslingen factory, Germany, streamlining production and increasing throughput.
Whereas each machine used to spend one and a half days at each of 18 stations, this has been reduced to one day at each of 15 stations.
Said Richard Kingsbury, managing director of the sole UK agent, Geo Kingsbury Machine Tools, to manufacturingtalk.com: "The reorganisation has helped to keep machine cost down while maintaining top build quality".
He added: "Further downward pressure on capital cost will result from economies of scale, as Index is planning to increase output of C-type machines by two-thirds in the second full year of production compared with the first".
The defining characteristic of the lathes that provides such high RF and stiffness concerns the actuation of the turrets.
Each is mounted on a front plate while an interconnected rear retaining plate is driven kinematically from behind the machine bed.
The system is so novel and difficult to visualise without seeing the machine in action that Geo Kingsbury has made a video of the lathe that it will send on a memory stick to interested companies.
* Sliding plate system - the critical advantage of the sliding plate system, said Geo Kingsbury, is that the distance between the turret centreline and the point at which it is driven is much shorter than for a compound slide.
The turret and drive plates are fitted with ceramic-coated, hardened tool steel strips at top and bottom.
These slide over a third plate of surface-hardened cast iron fitted into the bed, the latter plate being effectively sandwiched between the other two.
The parallel kinematic drive to the rear plate is now effected by two (rather than the previous three) ballscrew-actuated rods at the back of the machine, one vertical and one horizontal.
Glass linear scales provide positional feedback.
* Three turrets - there has been another alteration to the C-type design whereby three separate turrets are provided instead of one single-sided and one double-sided turret.
This allows greater flexibility of machining, especially when three tools are in cut simultaneously, said Geo Kingsbury.
They work like as follows.
* Turret 1 moves in X,Y and Z above the spindle centreline and works at the main spindle.
* Turret 2 mounted below the spindles operates in X, Y and Z at either end.
* The motion of upper turret 3 is restricted to the X-axis and works only with the counter spindle, which moves in Z.
Up to 14 tools in each turret allows 42 VDI-20 tools to be used, although if a user wishes to continue working with VDI-25 toolholders, 10 stations are available per turret.
Repeatability of tool tip position is +/-8 micron, even with angled tools up to 100mm long.
Tool drive is up to 8,000 rev/min at all positions.
* Three machine frame sizes - there are two sizes of machine frame, designated C100 and C200.
The former is the host for the 30mm and 42mm bar capacity spindles.
The latter (to be shown at MACH 2008) is for the 65mm and 90mm spindles.
Distance between the main and counter spindles is 510mm and 710mm respectively.
All models are fast acting, with 1G acceleration in X and Z up to 60m/min for the smaller machines and 50m/min for the larger models.
Main spindle rating varies from 9,000 rev/min/20kW for the smallest machine to 3,500 rev/min/23kW for the largest.
C-axis resolution is 0.001 deg.
The patented spindles are manufactured in-house and are liquid-cooled.
The liquid passes continuously through a chiller unit and is used to keep the electrical cabinet cool also.
* Geo Kingsbury Machine Tools at MACH 2008, NEC, Birmingham, UK, April 21-25, Hall 5, Stand 5190.
• Geo Kingsbury Machine Tools: contact details and other news
• Email this article to a colleague
• Register for the free Manufacturingtalk email newsletter
• Manufacturingtalk Home Page
Search the Pro-Talk network of sites
