JANUARY COVER STORY: All bases covered

[XYZ extends its product portfolio with new 5-axis machine]

Operating from its 98,000ft² headquarters in Burlescombe, Devon, there are few, if any, companies in the UK that can offer such a wide range of machine tool technology under one roof as XYZ. We’re talking 300 machine tools in stock worth in excess of £11 million, not to mention showrooms in Nuneaton, Blackburn and Waltham Abbey, plus a training facility in Sheffield.

But despite the eye-watering stock of machines on offer, if XYZ had an Achilles heel it was the lack of a cost-effective, fully-functional, simultaneous 5-axis VMC. That was until now. As Nigel Atherton, XYZ’s managing director explains, the introduction of the UMC-5X ‘The Challenger’ has effectively plugged this small, but vitally important gap.

“We offer Lehmann 2-axis rotary tables on our 1060HS VMCs as a retrofit 5-axis ‘solution’ and we’ve sold around 40 machines, but my sales guys have been pushing hard for a dedicated, simultaneous 5-axis machine for some time now,” he says.

“I actually first came across the UMC-5X about four years ago. The machines are manufactured in Taiwan but there’s a large 200-strong user base across a variety of high-tech industries in Russia, Germany, Spain and France plus more than 30 toolroom installations in Portugal.

“So, I visited a number of end users to fully evaluate the machines. I was so impressed that I sent my applications manager Mike Corbett to Taiwan to see the machines being built and assess the quality. Mike returned with an equally glowing report, but for a number of business reasons it was decided that the timing wasn’t quite right so we put things on hold with a genuine intention of revisiting the project soon afterwards. That’s where we are now and I know from first-hand experience that these machines are well-proven in the marketplace.”

From a specification perspective, one aspect that was top of Mr Atherton’s 5-axis priority list for any machine worthy of consideration was the use of a torque motor driven rotary table. “Worm and wheel configurations have inherent problems with accuracy and backlash not to mention additional maintenance requirements,” he explains. “With the UMC-5X we really want to hit the ground running by offering the best specification we possibly can. Linear scales are also provided as standard rather than as an optional extra.”

High interest

It seems a number of XYZ’s customers have already expressed a strong interest in the new arrival so to satisfy the early enquirers, Mr Atherton intends to host a series of ‘VIP Days’ in March 2017. For the more ‘just curious’ observers, there are open days planned soon after in Devon and Nuneaton. A machine will be on permanent display at the company’s Devon HQ and at the Nuneaton showroom later in the year. Mr Atherton reports that he believes he’s actually sold the first machine to an enthusiastic customer already.

“We have a client base of around 5,000 companies collectively operating more than 20,000 XYZ CNC machines in the marketplace,” he reveals. “We accept that not all of our customers will need full 5-axis simultaneous machining capability all the time and may well choose to run the machine in a 4+1 configuration, but there is an ever-increasing requirement to be able to hit five sides of a cube during the machining process to reduce time spent resetting components.

“I heard from a reliable source recently that in Germany, around 30% of the machine tools used have 5-axis capability; here in the UK, that figure is only 8%. Bearing this in mind, the UMC-5X offers a high degree of affordable future proofing.”

More bang for your buck

Whilst the UMC-5X represents an ideal, cost-effective machine for those looking to take their first steps into 5-axis machining, it’s certainly not entry-level as far as the specification is concerned. It will certainly ruffle a few feathers once it hits the marketplace in what is a very competitive arena but in terms of the price/performance ratio, you undoubtedly get a lot of machine for your money.

Weighing in at over nine tonnes, it features a compact 3,856mm (L) x 3,454mm (W) x 2,811mm (H) gantry-style design, that maximises the front loading working area while maintaining a relatively small footprint. Its construction incorporates solid Meehanite castings to create a rigid platform that allows high-speed, precise machining of complex shapes and forms across a wide variety of materials.

Initially, the design was conceived through a combination of Ansys simulation – software used to simulate interactions of all disciplines of physics (structural, vibration, fluid dynamics and electromagnetic) – and finite element analysis techniques to deliver a machine with maximum stability and reduced vibration even under heavy, highly dynamic, cutting conditions. This versatility and lack of compromise in its design makes it an ideal solution for the multi-axis machining of parts for a wide range of industries, including aerospace, medical, automotive and mould and die.

Fully featured

XYZ’s strength as a machine tool provider is the ability to supply quality machines, direct from stock within short lead-times so much of the company’s business tends to be centred around the sale of ‘off the shelf’ equipment. The UMC-5X will be no exception but it does offer a choice of spindles however ranging from 12,000/15,000rpm in-line direct drive variants with 25/35kW motors through to high-power, high-speed, 18,000/24,000 core-cooled motorised units with 20/25kW motors.

All spindle options are equipped with a high pressure through spindle coolant system. The 600mm diameter C-axis torque-driven table can take components weighing up to 600kg yet it remains mobile with maximum rotational speed of 90rpm. This is combined with feed rates of 36m/minute in the X-, Y- and Z-axes with agility aided by 7m/second acceleration.

The tilting A-axis, which has a tilt range of ±120°, with full rotation in under 2.5 seconds, has a feed rate of 16.6rpm. Both the A- and C-axes also benefit from rotary linear encoders accurate to ±5 arc seconds and linear scales are standard in X, Y and Z. Rapid tool changes are provided courtesy of a side mounted 24, 32, 48 or 60 tool ATC.

So smart

On the CNC front, XYZ will offer the machine with either Siemens 840DSL control or Heidenhain iTNC640 HSCI, both of which have traori/kinematic options and fast block processing capabilities essential for simultaneous 5-axis machining. The UMC-5X also benefits from integrated Smart Machining Technology (SMT) to further improve machine performance. SMT comprises four key elements: Tool-Tip Positioning Control (TPC); Spindle Vibration Supervision (SVS); Metal Removal Rate Optimisation (MRRO) and Axial Accuracy Control (AAC). SVS and MRRO are optional.

“The concept behind SMT is to provide overall savings through reduced energy costs, improved efficiency and lower running costs,” Mr Atherton advises. “It continually monitors spindle vibration along with spindle thermal displacement and deformation resulting in high quality surface finishes, higher accuracy and faster cycle times.”

SMT is a real bonus for a machine at this price point. Looking at the four key elements in more detail: TPC, offered as standard, provides real-time monitoring of any spindle thermal growth using an embedded measurement system. Data collected is fed back to the control and offsets are adjusted in real-time, generating improvements in accuracy of between five and six times that achievable when the system isn’t employed.

Similarly, the SVS option uses embedded motion sensors to monitor spindle condition and reacts accordingly to different levels of vibration – level one being a notification to the operator, level two automatically reducing cutting data, and level three actually stopping machine to prevent damage.

Optional MRRO also makes use of characteristics of the machine, cutting tool, workpiece and control to maximise the cutting condition. The system automatically uses this information to enhance cutting data with improvements of up to 14.3% in metal removal possible and surface finish improved by up to 61.5%.

Last but by no means least, the standard ACC offering helps combat overall thermal growth in the machine thanks to integrated thermal sensors that constantly monitor its temperature. ACC is automatically activated with temperature fluctuations to overcome thermal deformation and improve consistency and accuracy.

Pain free transition

Mr Atherton concludes: “We looked long and hard for the right 5-axis machine that offers both an uncompromising range of features and value for money. With the UMC-5X, I believe we now have a machine to meet the needs of a wide variety of customers, from those just starting out in the 5-axis arena, to those already well-versed in this technology.”

XYZ realises that making the transition into 5-axis machining can be a daunting prospect so, within the first year of purchase, training is described by Mr Atherton as ‘almost unlimited’. Also within the first year, if an operator leaves the customer’s business, XYZ will train another operator free of charge.

XYZ Machine Tools www.xyzmachinetools.com