Each production line is a potential source of metallic impurities, which in turn has a negative impact on the purity of the manufactured product, or constitutes a threat to the machinery and equipment, which is a part of the line. The manufacturer often uses intermediate products. Their purity in terms of metallic impurities often leaves much to be desired.
To protect against the negative influence of metallic impurities in the production process, one can secured himself/herself through the usage of devices detecting their presence. Since the early 1990s, Eljot collaborates with Sartorius Aachen GmbH (formerly Boekels) in the supply and installation of metal detectors for each industry on the Polish market. Our detectors guarantee absolute purity of the products in terms of metallic impurities.
The multitude of types and solutions of metal detectors we offer allows us to provide solutions for every type of industry.
Taking into account the whole range of products, we can distinguish two main groups of metal detectors i.e. ones dedicated for the food industry and ones for the use in heavy industry. Intermediary industries are implemented, when appropriate, through individual selection of the solutions from the these major groups of products.
The work principles of a metal detector
The operation of a metal detector relies on the magnetic field disturbance generated by the detector transmitter antenna, which are caused by moving metal. This disorder leads to the induction of disequilibrised voltage, which is recorded by a receiver of the detector coil. The detector evaluative electronics are responsible for the signal analysis.
The physical analysis of "metal" signal informs us about the size of the detected metal (signal amplitude) and the nature of the metal (pulse phase).
After detecting metal, the "metal" signal is transmitted to the separating device such as an electromagnet, which pulls out the ferromagnetic impurities from the product, by dint of the arrangement of evaluative electronics outputs of the metal detector. In the case paramagnetic (non-ferrous metals, stainless steel) contamination, we use mechanical separation systems (collapse, deflectors, vanes), because of their "transparency" for the magnetic and electromagnetic field.
The most popular application in the heavy industry is a metal detector from the SECUS-D series in conjunction with evaluative electronics SECUS-E. The advantage of SECUS-D series is the fact that the antenna design of the detector is split, allowing for its assembly without the necessity to cut the conveyor belt.
The MDB-UB series is the second of the most popular applications in the heavy industry. The detector antenna is mounted directly beneath the conveyor belt. The little dimensions of the antenna are an advantage of this design. However, its detection ability decreases with distance from the belt. Therefore, this type of application is applicable in the case of a low feed.
The VISTUS-C series detectors are the primary application for the food industry. They are of a monolithic construction mounted on both the customer's existing conveyor belts, as well as, conveyors which were manufactured by our company.
The evaluative electronics of the detector are embedded in the antenna in the standard version.
However, there is a possibility to order a solution with separate electronics, so you can put it in the control room or other convenient site for maintenance. The antenna and electronics are made of stainless steel. We can also provide a special version with a higher degree of protection which allows to wash the machine under pressure with measures used in processing of meat or fish.
After the discovery of the metallic impurities, one can use various methods of its elimination from the average retention strap through pneumatic muzzle booster systems, mechanical steering wheels or clack valves, sashes and slopes at the dumping. Conveyor belts used under metal detectors, which are supplied by our company, have a very wide range of shapes, and additional options. The final selection of applications is received after a detailed analysis of the customer's needs.
We have VISTUS-R series detectors available in the case of gravitational transport of the product.
The build up applications may have different shapes and peripheral components, however, they always consist of an antenna detector, separate evaluative electronics, a pipe forming a metal-free zone, and the actuator which acts as a two-way splitter.
Separation of the metallic impurities from friable product in gravitational transport works by directing impurities along a different track together with a portion of the product. The use of rapid pneumatic systems reduces the loss of good product to a required minimum.