In 2009, the Austrian company Hammerer Aluminium Industries (HAI) built a casthouse for aluminium extrusion billets in Santana, Romania. A modern Hertwich continuous homogenizing furnace with ultrasonic testing, saw and packing unit was put into operation for the homogenization of the extruded aluminium billets. At that time, the plant’s annual production was 80,000 t.
The batch homogenizing furnaces currently on order complement the existing continuous homogenizing furnace in several respects. Initially the new plant will increase the capacity by around 50 %. In addition, production becomes more flexible because continuous homogenizing is less suitable for more frequent changes of homogenizing parameters or for alloys with very long holding times. In such cases, the batch homogenizing furnace brings to bear its advantages. In the case of Hammerer Aluminium in Santana, there is also the option of using batch homogenizing furnaces for the heat treatment of the rolling slabs newly added to the production programme.
For this reason more and more foundries have recently started to combine continuous and batch homogenizing furnaces. Meanwhile the combination of continuous and batch homogenizing furnaces may even be considered as state of the art in modern casthouses. As described above, this combination offers full automation, so that the ancillary equipment for sawing, ultrasonic testing, stacking, strapping etc. can be used by both plants. In the case of Hammerer Aluminium in Romania, additional handling equipment will be installed alongside the extension of the existing ultrasonic facilities.
The trend towards the combined operation of continuous and batch homogenizing furnaces was initiated when Hertwich took a critical look at the conventional batch furnace design a few years ago and came up with some technical innovations. The newly developed batch furnaces are not only similar to the continuous furnaces in terms of temperature distribution, but their operation is also highly automated with the help of suitable equipment. The market’s attitude to the new generation of batch furnaces was quite critical for some time, but now the industry is fully convinced of its benefits.
_{(Source: SMS group)}