Weighing and metal detection specialist Sartorius has developed a new kind of metal detector for the food industries, utilising a breakthrough in sensor technology: it will be unveiled at Total 2004

Weighing and metal detection specialist Sartorius has developed a totally new kind of metal detector, utilising a breakthrough in sensor technology. The Sartorius Observer makes it possible to detect ferrous and stainless steel contamination in aluminium foil wrapped products with a metal detector. Conventional detectors that operate on the basis of electromagnetic alternating fields bump up against their limits when they encounter packaging, or parts of packaging, made of aluminium.

Tests using X-rays are expensive and require elaborate safety measures to ensure protection against radiation.

For the Observer metal detector from Sartorius, the composite packaging of food in sachets, ready-to-eat meals, aluminium lids on yoghurt, and blister packages of tablets are no problem at all.

Because aluminium does not have any magnetic properties, it is practically "transparent" for this metal detector.

The Observer is also impervious to interference, such as that caused by the product to be examined and by metal parts in the surrounding environment.

This is possible thanks to the specific calculating operations used by the metal detector, that eliminate noise or stray fields in the signals received by the highly sensitive built-in sensors.

This sensor technology and specific evaluation electronics has been jointly developed by Sartorius and STL GmbH of Constance in Germany.

Besides testing aluminium-packaged products in the food and pharmaceutical industries, further applications for the Observer metal detector include detection of product flow in stainless steel pipes.

The Observer metal detector not only serves the needs of consumer safety, but can also indicate defects in machinery well ahead of time, such as loose parts, before they can do any real damage.

It can even detect stainless steel particles, such as AISI 304, under certain conditions.

As a result, the Observer metal detector offers technology that is unique throughout the world.

The Observer will be unveiled at Total 2004 in March, on the Sartorius stand in Hall 4 of the NEC.