Ruf briquetting machines help Trumpf increase output in laser component manufacturing.
In order to ensure the highest possible output and productivity when machining aluminium, for the last two-and-a-half years Trumpf's laser components production unit has been operating as a fully-automated machining centre. It can operate unmanned for up to 60 hours, but to do this it needs both robots and a sophisticated system for dealing with swarf. This latter problem has been handled from the outset by a tailored RUF RAP 4/2600/80x40 Integration Press which processes waste aluminium into practical briquettes and - along the way - increases the value of this raw material.
The high-tech company Trumpf Machine Tools is internationally renowned for its high-quality and reliable products and services. This is based on highly-efficient processes which have been fully taken on board by all the company's staff and management through the firm's own 'Synchro' production system. In this way, it is just as important for internal supply departments to deliver 'just in time' as it is for external competitors.
Alexander Wassmer, section leader of around 30 staff in Trumpf's laser component production unit, explains what this means: 'We manufacture various aluminium components for core assemblies which are used in the beam generators of CO2 lasers. We are competing directly with external manufacturing plants and so always have to be able to supply at low prices and within a strict time frame.'
The laser components production unit often has to deal with small lot sizes, even as low as a single piece, as the Trumpf beam generator assembly area does not hold any stock. As a result, just-in-time delivery is critical, which requires high levels of flexibility and productivity in machining operations. To achieve this, a decision was taken at Trumpf two-and-a-half years ago to invest in a robot-controlled, fully-automated five-axis milling centre: 'Our main aim was to be able to run the plant unmanned for a whole weekend if necessary', explains Alexander Wassmer, adding: 'We realised that the huge amounts of aluminium swarf produced would be a challenge, as they could not be disposed of if weekend shifts were running unmanned. So we had to find a solution to this problem.'
Various ideas were gathered and discussed, and in the end it came down to using a macerator or a briquetting machine. The decision was pretty easy to make, because briquetting offers significantly better volume reduction while at the same time increasing the value of the swarf. The decision-making was also helped by finding a medium-sized company like Ruf which could fulfil all of Trumpf's technical and commercial expectations and requirements with its compact Ruf Integration Press RAP 4/2600/80x40
The Ruf briquetting press soon paid for itself
After two-and-a-half years of using the machine, Alexander Wassmer is still firmly convinced they made the right decision: 'The machine works just perfectly. We have even operated it unmanned for up to 60 hours in our complex milling centre operation without any problems at all. This alone means that it paid for itself in no time at all.' There are also many other advantages. The compacted aluminium swarf can be sold at a much higher price, while taking up much less space and simplifying downstream processes.
Trumpf's fully-automated five-axis milling centre produces around 20 tonnes of metal swarf per year. Around 80 percent of this consists of the expensive aluminium alloys: AlMg45Mn and AlMgSi1 (also as Si0.7 and Si0.5). The remaining 20 percent is made up of swarf from steel, stainless steel and copper. The swarf produced can also vary greatly: some types are short and several millimetres thick, others are only one-tenth of a millimetre thick and very long. But this is not an issue for Alexander Wassmer, because 'the RAP handles all kinds of swarf without any problems, turning wet, high-volume waste into small, compacted briquettes which on average only take up one-twelfth of the original space requirement.'
Save on valuable working time
All swarf is processed in the same way in the state-of-the-art production centre thanks to the integration press which has been customized to meet its exact requirements. A hopper collects the swarf at the back of the machine and it is then transported by screw conveyor to a pre-compressor where it is compacted, discharged and transported to a nearby container via a special small conveyor. Technician Thomas Krayer operates the automated machining equipment and also looks after the swarf disposal.