One of RUF’s briquetting presses has simplified Alcutec’s aluminium milling production processes
Precision and efficiency are top priorities for Alcutec GmbH. To this end the aluminium milling specialists have installed a RUF briquetting system which presses the aluminium chips produced during production into compact briquettes. The briquetting process reduces the volume of the chips markedly and in addition clinging cooling lubricant is recovered. The result is that the production waste is much easier to handle and achieves higher prices when sold than loose aluminium chips.
Alcutec GmbH has developed a good reputation among its customers in its sector of business – milling medium sized lots of challenging and highly exact aluminium parts. The company has grown dramatically since its inception 25 years ago. In the beginning, the two company founders worked with only the help of a part time worker, whereas today the firm located in Königsbrunn has 15 employees with roughly 2 million euros turnover per year. The name still reflects the original business concept: machining aluminium (Al) and copper (CU). However the Swabian Company has been focused on the lighter material side for many years now.
The machining plant has grown analogously with the increasing demands for quality parts, for complexity and ever growing unit quantities. Currently the Company from Königsbrunn is producing on eight 3, 4, and 5 axis machining centers. To guarantee the required precision, the parts are measured to a tolerance of micrometers with a CNC controlled and a hand controlled coordinate measuring system. The dimensional accuracy is of course controlled at the start of production of every new part. However, as David Kubis who is responsible for Order Management/Purchasing emphasizes, “when it comes to particularly demanding parts we also measure in-process in order to react to deviations and correct them immediately.” The tensions present in the purchased aluminium block can be enough to produce deviations in the end milling result so therefore adjustments must be made as the process is being carried out.
Alcutec GmbH…
...as a contract manufacturer is specialised in milling complex aluminium parts at a high level and consistent quality for series production. The company is located in Königsbrunn, a few kilometers south of Augsburg. The focus on complex parts leads to the situation where their manufacturing experts often give advice to their customers during the development of the parts, particularly when functionality and producibility have to be given equal emphasis. In addition to the milling service, Alcutec also offers assembly of components and can deliver the parts with surface coating when required. Thanks to the round the clock production and component design on their own in-house CAD-CAM work stations, the shortest lead times are possible. Alcutec`s products are used in the most diverse branches of industry: the main focus lies in machine and plant engineering, measuring technology as well as placement automation.
A leap in productivity thanks to the new machining centers
In order to remain competitive in Germany, Alcutec continuously works on improving their productivity. In this respect a milestone was reached when two horizontal 4 axis CNC machining centers were procured, linked with a 24 pallet handling system. The automation achieved herein led in no small measure to the fact that the employees can run the plant in two shifts almost around the clock. The late shift sets the system up in such a way that it can continue running through the night. “More enormous increases in efficiency have been brought about by the introduction of an electronic tool management system” reports David Kubis. Thanks to the transparency about all available and already set up tools, working time can be saved and of course tool costs can be reduced.
However, to best utilise the possibilities for efficiency and quality in milling, further optional processes are necessary. In the past these processes were often disturbed by numerous barrels of aluminium waste. “The light and high volume chips caused us enormous space problems in the hall. Storing them in the outside yard was not possible for various reasons.” David Kubis continues: “We are talking about serious amounts here. Depending on the geometry of the produced parts, we could have been producing an average of one container of waste per week.”
Loose chips had negative impacts on the machining processes
Dealing with this amount of chips disturbed the production processes markedly. Alcutec`s MD Jochen Schwarz saw this as a situation he definitely wanted to change. As a man who is always open for new ideas and solutions, he very often participates in meetings with other managers responsible for machining firms. During one of these exchanges of ideas Mr. Schwarz came across a modern briquetting system from RUF. It became immediately apparent to him that Alcutec could put this technology to use. As the RUF machine was reliably functioning in his management colleagues’ plant, the decision for the Zaisertshofen manufacturer was a quick and easy one.
Following informative consultations with RUF`s representative Andreas Jessberger the RUF 4/1700/60x40 briquetting machine was purchased in 2010. A decision which has proved to be worth its weight in gold in a very short time, as dealing with chips became a much simpler process. An employee uses a manual pallet jack to lift the tipping container, full of aluminium chips, over the large feed hopper of the system and tips the contents in. All other steps of the process are carried out automatically. A sensor registers that there are chips present in the hopper and starts the press. When the hopper is filled, the system runs until the chips have been completely processed.
The specific compaction pressure of 1700 kg/cm² of the 4 kW engine compacts the aluminium chips and creates briquettes in the 60x40 mm format. These aluminium briquettes are automatically conveyed to a waiting collection bin. When all the chips have been pressed, the system stops automatically. The density of the briquettes lies between 2.0 and 2.1g/cm3 and the bulk volume sinks remarkably through the briquetting process: typical values for loose aluminium chips lie between 0.15–0.2 kg/l, however a value of 1.4–1.5 kg/l can be achieved with briquettes. The maximum throughput capacity of the briquetting system lies at around 100 kg/hr.
Briquettes achieve higher prices that chips
Apart from the simplicity of handling, Alcutec are also delighted about other benefits which add to the sales value of the product waste: during the briquetting process almost all of the clinging cooling lubricant is recovered. In part, emulsion drops into the collection bins at each milling center and is captured. The largest percentage however is pressed out in the briquetting system and collected in a catch basin. An integrated vacuum pump in the basin pumps the emulsion into waiting barrels for later disposal.
“And so our handling and space problems are solved to perfection” summarises Kubis. In their compact briquette form and freed from clinging cooling lubrication, the aluminium waste achieves higher resale prices.
