Is it compulsory to install a metal detector in a chain of food
The most important cause of food pollution is certainly the continuous contact of food
with metallic equipments. To face this problem, In Italy there is the D.L.n. 155 of the
26/05/1997 that imposes the control of the critical phases of the production process in
order to respect the directives HACCP.
The missing control of such norms, can involve remarkable economic penalties. Moreover it
is necessary to keep in mind that many chains of great organized distribution (G.D.O.)
demand and will demand to their suppliers products which have been submitted to rigid
controls. The use of metal detectors on the food production lines protects both the final
consumer and both the same productive system, avoiding serious damages, neither problems
of legal nature and image.
Is it possible to find exclusively ferrous material?
Not! the ferrous materials are easier to detect and therefore they can be find more easily
inside the product. The non ferrous materials (branch, lead and aluminum) are not
magnetic, but they are equally easy noticeable. The stainless steel, the most used are the
304 and the 316, are not sensitive to the magnetization and have an insufficient
electrical conductivity, therefore the survey becomes more difficult. "Metalim"
works with very high frequencies, consequently it is able to detect without problems
ferrous and non ferrous metals.
Are the frequencies used from the Metal detectors harmful for the
The intensity of the field generated by the Metal Detector does not create dangers for the
In which productions the Metal Detector for the food industry can
find its application?
" Metalim' finds its application in all fields of the food industry: cheese,
conserves, working meats and cold cuts, macaroni factories, oil mills, rice, ice creams,
dept freeze, confectionery, sugar, yield and vegetables, leaven, catering, etc.
What are the factors which can influence the sensibility of "
the Metalim " and the metal detectors in general?
* Type, mass and shape of the metal;
* dimensions of the tunnel passage
* position of the element in the tunnel passage ;
* type of product
* environmental conditions
* speed of passage.
Some products, like the meat just slaughtered, the cheese, the bread just taken out of the
oven, conserves, etc, can influence the metal detectors. Its necessary therefore to
make some tests on the alimony to control in order to find among 150 programs and 256
sensibility levels, the optimal values for the single phases of working of each product.
When evidenced the undesired presence of metallic parts is it
possible to carry out only the refuse of the polluted product? "
Metalim " can command switching electric valves or robot for the mechanical refuse;
It can be connected to optical and acoustic sensors and also to checkweighting systems. It
is practically free from false alarms even if it is equipped with high sensibility and
strong discriminating power. On the pipes is generally installed a pneumatic valves with a
piston which arranges to the automatic shunting line of the polluted product.
Who adjust and put out the system?
It is very important to establish on the metal detector the best sensibility obtainable
for every product , considering the type, dimensions and the packing. This adjustment has
to be effected in collaboration between the manufacturer and the users during the final
regulation of the system. Frequent tests of survey of metallic parts must moreover be
carried out by using test samples which contain ferrous and non ferrous metallic polluting
agents in order to check eventual debviation of the defined standards.