Company also operates one of the very first ZPF furnaces built in 1993
Economical, environmentally friendly aluminium melting technology has always been the prime focus of ZPF therm Maschinenbau GmbH since it was established. Since November 2013, these tried-and-tested and continuously improved melting furnaces are being produced under the name ZPF GmbH. The first installation was already delivered in February, not entirely by chance to a customer who is still operating six first-generation ZPF furnaces from 1993 - to Metallwerk Friedrich Deutsch GmbH, market leaders for ski edges and a major supplier to the automotive industry. Due to their positive experience and satisfaction with the furnace engineering from Siegelsbach in the past, the decision was taken to continue the working relationship with the new ZPF company. Meanwhile, the plant is running at full capacity and has already proven to be exceptionally economical.
The metal-working factory Friedrich Deutsch in Innsbruck is primarily known for its pre-shaped and partly pre-finished steel edges for the ski and sport industry. In addition, the company manufactures pressure die-cast aluminium components for all the prominent car producers in Europe – several thousand tonnes of material are melted at their mill every year. So far, this work has been done by six melting and holding furnaces from ZPF therm in 24-hour continuous operations. “An expansion was, however, necessary for capacity reasons”, explains Hubert Tilg, manager of the die-casting division. “Because we were absolutely satisfied with the existing furnaces and they offer an excellent price-performance ratio as well, it was clear that we would again opt for ZPF.” A further factor was that, because of their familiarity with these melting facilities, the staff at the metal working factory can continue to carry out most of the maintenance work on the new furnace themselves.
In only three months, the required installations were manufactured in Siegelsbach in the state of Baden-Wuerttemberg and delivered to the customer. The system consists of an aluminium melting furnace with a melting capacity of 1,500 kg/h and a holding bath for 5,000 kg, an attached charging machine, and a 17” filtering furnace for cleaning the molten metal. “Thanks to its size, the new melting furnace yields much better energy values and is thus even more economical than the previous systems,” says Mr Tilg. “Apart from that, the larger charging system doesn’t need to be loaded so frequently, a further factor which reduces energy consumption and increases performance.”
Saves energy and reduces emissions thanks to special construction
ZPF furnace engineering aims generally at keeping the energy consumption as low as possible and implements flue gas reversal to achieve this. With this principle, instead of the hot flue gases from the melting process being discharged straight away, they are routed inside the furnace in such a way that their heat can be used to hold the molten aluminium at a high temperature. In addition, the combustion chamber made of refractory concrete acts not only as a separating layer between the aggressive liquefied aluminium and the outer shell of the furnace, but also as insulation, reducing the emission of heat to the surroundings and functioning as an energy accumulator. It is consequently much easier to keep the temperature inside the furnace at a constant level. In combination with the waste gas recirculation, the fuel requirement is very low making the furnace particularly efficient and environmentally friendly. At the same time, the longer route of the waste gases inside the melting system brings about lower emission values since practically all pollutants are burnt in the post-combustion process at over 800 °C. This means that ZPF installations can be used without flue gas filters.
Besides this, ZPF technology also has an impact on the melting quality and on the maintenance costs: the waste gases remaining inside the furnace generate a slight overpressure which prevents any additional oxygen from entering. The adverse reaction of oxygen with aluminium – which would cause corundum to form in the melt and on the inside walls - can consequently be kept at a very low level. This technique achieves both a higher degree of purity in the liquefied aluminium as well as reducing damage to the refractory walls, thus avoiding expenditure for relining and repairing the plant.
Contract is continuation of long-standing business relationship
The melting furnace has been working to full capacity without any problems since being commissioned in February. “We already have one of the first – if not the first – furnace made by the former company ZPF therm, and that is still in operation today. And we will continue working very closely with ZPF”, explains Michael Deutsch, CEO of Metallwerk Friedrich Deutsch. “ZPF is a partner with true ‘handshake reliability’ with whom you can go through the ups and downs of life. As a result of the new ownership, our confidence has increased even further.” The company is already considering ordering a further furnace in the medium term as an additional safeguard for the event of breakdowns.
Metallwerk Friedrich Deutsch GmbH was founded in Innsbruck in 1947; the core business at the time was welding engineering. In 1957, the factory started producing metal components for the ski and sports equipment industry in which the company has since become a market leader. In addition, the aluminium die-casting segment was established which today supplies sophisticated components to the automotive industry throughout Europe. Altogether about 250 people are employed in both divisions of the metal-working company.
In 2013, ZPF GmbH emerged as the successor of ZPF therm Maschinenbau GmbH, which was founded in 1993. Like the former company, ZPF GmbH focuses mainly on the development and construction of highly efficient aluminium melting furnaces. In addition, the product range includes chip melting and holding furnaces. The installations are produced in Siegelsbach in Baden-Wuerttemberg and pre-assembled to the greatest possible extent before being shipped to metal-working enterprises worldwide.