Production times almost halved

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industrial

Production times almost halved

Contract manufacturer is reducing production times with the Heckert five-axis machining centre with turning function

“Only the best is good enough for our customers,” says Karl Kordik, who is responsible for the area of contract manufacturing at Neuson Hydrotec GmbH in Linz. With the new Starrag HEC 800 X5 MT machining centre, his machining team is even able to machine complex housing with numerous holes at different angles with maximum precision – in a single clamping position and in half the time. The “best” is therefore also a clear advantage for Neuson Hydrotec.

Neuson Hydrotec GmbH in Linz is a company in which mechanical engineering, mechatronics and hydraulics are intertwined in many ways (see box). With around 50 employees, contract manufacturing is the largest business unit. Walter Füreder, who is one of the two GmbH managing directors responsible for this division, describes it as essential for the entire company: “We generate around half of our turnover with our contract work. Twenty per cent of this involves doing groundwork for other business units, while we achieve the rest with leading companies in the plastics recycling, railway and mechanical engineering sectors.”

Karl Kordik, Sales Manager for Contract Manufacturing, has known his customers and their needs for many years. He explains that many long-distance trains around the world, such as ICE, Railjet, etc., have a component that has been manufactured by his company – “namely a wheelset bearing housing, of which we have already manufactured tens of thousands in different variants”. Components for injection moulding machines are also part of the recurring contract work, as are shredder shafts, bearing blocks, etc., which are supplied to machine tool manufacturers. “We supply the largest proportion of our work, around 40 per cent, to the plastics recycling sector,” says Kordik. “Like us, the world’s largest and most important system manufacturers are based here in Upper Austria, and we can count most of them among our customers.”

Neuson Hydrotec’s contract manufacturing has a lot to offer – starting as early as the development support phase, which includes advice on production-ready design. The services we offer range from the procurement of raw material to CNC milling, grinding, lapping, honing, welding and superfinishing, right up to pre-assembly. Karl Kordik is aware that “our customers appreciate the fact that we supply them with a complete component, including a 3D measurement report.” Since 2023, the contract manufacturing division has had a large 3D coordinate measuring machine, which can confirm the quality produced and can also ensure process optimisation.

Sophisticated components, powerful machines

The central topic in contract manufacturing is machining, and various CNC turning and grinding machines as well as several machining centres with a pallet pool are available for this. The highlight is the HEC 800 5X MT five-axis machining centre, which was put into operation in May 2024. This investment was triggered by a complex component for a plastics recycling machine that requires turning and milling operations, and in which numerous holes have to be drilled at different angles. In this recycling plant, the used plastics are heated to around 400 degrees after shredding. A spindle presses the liquefied mass through a plate with tens of thousands of holes about 0.2 mm in size – called a laser filter – which retains any contaminants. These are removed by a permanently rotating scraper disc. The cleaned plastic flows onwards to a cooling station, and is then cut into pellets. Neuson Hydrotec manufactures the housing for this laser filter. It contains intricate contours and numerous channels, through which first the contaminated and then the cleaned plastic flows. “One hole runs through the entire component, and other channels meet at a certain angle,” says Karl Kordik, explaining details that are difficult to produce. High precision is particularly important for the latter. This is because, for fluidic reasons, the channels must not be offset when they meet. “We manage this because we achieve a positioning accuracy per hole of less than 0.03 mm,” adds Kordik. “Although that doesn’t sound particularly difficult, the value corresponds to only a few μm per axis if the holes are drilled at 45 degrees.”

The surfaces of the holes are also of decisive importance for a smooth flow. That is why they are sanded and polished by hand. The finer the surfaces coming from the machine, the less reworking is required.

“ We want to clamp components with a length of 1100 mm, and drill through them completely with an appropriate tool.”

Karl Kordik, Sales Manager Neuson Hydrotec

Complete machining saves non-productive time

Until recently, the contract manufacturers were producing this housing on a vertical turning and boring mill and a three-axis milling machine, in a total of seven clamping positions. When the customer ordered significantly larger quantities, Neuson Hydrotec decided to modernise production in this area – primarily to achieve shorter manufacturing times. The solution pursued was complete machining on a five-axis machining centre witha turning function. The vertical turning and boring mill was to make way for a machine like this. “We had shortlisted four machines,” explains Karl Kordik, who also oversees production in addition to his role as Sales Manager. There were several reasons why the decision was made in favour of the HEC 800 5X MT. According to Kordik, one important factor was that the HEC 800 allows the component to be clamped vertically: “These components can only be clamped on a horizontal turning and milling centre with great difficulty. Fast, automated workpiece replacement is even more difficult. The HEC 800, on the other hand, already comes with a dual pallet changer as standard, which enables setup parallel to the primary processing time.”

Another argument in favour of the Heckert machine was the fifth axis. On the HEC 800 5X, this is located in the workpiece and not in the tool.

Bed extension for deep holes

Another argument in favour of the Heckert machine was the fifth axis. On the HEC 800 5X, this is located in the workpiece and not in the tool. “That saves us from having to reclamp,” says Kordik. Ultimately, however, the decisive factor was the possibility of obtaining a bed extension along the Z axis and an extended Y travel path. Kordik describes the background: “We want to clamp components with a length of 1100 mm, and drill through them completely with an appropriate tool. The standard Z travel path of 1300 mm is not sufficient for this.” Starrag finally supplied the HEC 800 5X MT with travel paths of 2050 mm along the Z axis and 1300 mm along the Y axis. “At moderate costs,” says Karl Kordik, adding that “no other machine manufacturer had offered such extensions. We would have had to switch to much larger machines, which would, however, have been more expensive and would have been associated with reduced dynamics.” Instead, Neuson Hydrotec preferred to invest in useful additional equipment, such as a cooling lubricant temperature control system. “Our roughing operations generate a lot of heat, which would otherwise be transferred into the cooling lubricant and onto the component. But this would run the risk that, when it comes to generation, the exact fit sizes would no longer be correct after cooling.”

“ Essentially, it’s the reduced non-productive time that has an impact.”

Karl Kordik, Sales Manager Neuson Hydrotec

Interpolation turning instead of reclamping

The control software for interpolation turning was also on our ’to-buy list’. This is because the laser filter housing requires a 350 mm hole that is offset from the centre by 8 mm. “Thanks to the precisely controlled interpolation of the X and Y axes, we can create this without any problems,” confirms Karl Kordik. Alternatively, his production colleagues would have to take the additional step of clamping the component so that it is centred on the hole. According to Arno Berger, the responsible regional salesman at Starrag, this can also be done without any problems: “We have tested this. Despite the imbalance that then occurs on the quickly rotating table, we are in line with all required tolerances.” However, it saves more time if you produce the eccentric hole using interpolation turning.

Success can be seen after just a few weeks. In the case of the filter housing described, it was actually possible to reduce the number of clamping positions from seven to one. “The time saving is 48 per cent,” says a delighted Karl Kordik, who had campaigned for this investment. “Essentially, it’s the reduced non-productive time that has an impact.” And he mentions yet another advantage: “As the component is now on the machine for longer, the operator has more time for other tasks.” The Heckert milling and turning centre also pays off when machining other components. “Now that the vertical turning and boring mill is no longer available, we also use the HEC 800 5X MT simply to produce turned parts. Even here, we are around 20 per cent faster than before, which is due to the use of multi-cutting tools, shorter tool change times, faster rapid traverse, etc.,” says Kordik.

He had hoped for such savings – or rather, he had expected them. After all, back when he bought the new machining centre, he had already negotiated the possibility of a second, compatible Heckert HEC 800 – an opportunity which he will probably take up soon.