Foundry process

The entire industrial foundry process controlled from our plant

From moulding to casting and even storage, we monitor all stages of the process

Zanardi Fonderie, with its 3 electric furnaces, each with a 28 t capacity, and automatic moulding line measuring 900 x 710 x (250 + 350) mm, produces cast parts in spheroidal graphite iron (GJS), austempered ductile iron (ADI) and isothermal ductile iron (IDI) using the green sand moulding process. The castings, predominantly in medium production runs, can reach up to 120 kg.

Thanks to the recent installation of ITACAX software in both the melting furnace and pouring departments, we have taken an enormous leap forward in terms of control of the foundry process and thermal analysis.

A moulding line for small and medium production runs in spheroidal graphite iron (GJS), austempered ductile iron (ADI) and pearlitic isothermal ductile iron (IDI)

Zanardi Fonderie is equipped with an in-house moulding, cooling and shake-out line, called “Savelli”, able to process up to a maximum of 220 flasks per hour. The dimensions of the moulding flasks are 900 x 710 x (250 + 350) mm or 36″ x 26″ x (10″+14″). Two moulding machines with “Forminpress” technology are used to create the upper and lower moulding flask.

Our moulding line is suited to small and medium size production runs, from a minimum of 50 foundry flasks per batch, of castings in spheroidal graphite iron (GJS), austempered ductile iron (ADI) and pearlitic isothermal ductile iron (IDI) using the green sand moulding process.

Melting plant with 3 electric furnaces, controlled by ITACAX software for thermal analysis

Our castings in spheroidal graphite iron (GJS), austempered ductile iron (ADI) and pearlitic isothermal ductile iron (IDI) are melted in three electric furnaces each with a 28 t capacity and 3,300kW of power. Throughout the entire melting process, an efficient air filtration system ensures the extraction of fumes produced during each stage: ladle loading, slagging, magnesium treatment.

Since the end of 2017, Zanardi Fonderie has worked with the ITACAX foundry process and thermal analysis control software, a highly sought investment in order to integrate process data with all company databases, thus obtaining a more sophisticated and faster level of data processing, in addition to improved process traceability.

The ITACAX software is installed in the melting furnace area and performs a detailed analysis of the base cast irons. For example, thanks to thermal analysis, it is possible to quickly determine the chemical analysis of the base cast iron through an accurate estimation of the thermal Ceq.

A technological pouring system, completed by quality testing of materials

Our “Progelta” pouring system consists of an unheated pressurised casting ladle, with 4 t capacity. During the pouring process, the molten metal undergoes inoculation, a very important step in counteracting shrinkage defects and therefore enhancing the properties of the casting. Regular and important quality tests are then carried out on the material in regards to its nodularity, temperature, chemical analysis and thermal analysis.

The benefits of ITACAX software for ductile iron monitoring

During the casting process, the ITACAX software is very useful in monitoring the final ductile iron. Thanks to the thermal analysis, it is in fact possible to rapidly assess the effect of inoculation on the quality of the ductile iron, also providing an indication as to the shape of the spheroids.

ITACA Stream (inoculator), through its video camera system (ITACA Vision) allows us to dynamically control and guarantee the correct intake of inoculant for each single flask. The inoculation is therefore elaborated in real time and adequately indicated to the line operator, thus guaranteeing total control over the process.

At the end of casting, all flasks are stored in a dedicated warehouse for the time necessary to allow the material to cool and solidify in accordance with the set times and methods, in order to obtain the desired microstructure and avoid the formation of dendrites and segregations.

An internal storage area for raw materials: cast iron ingots and scrap, ferroalloys, alloys and ancillary materials

The Zanardi Fonderie production plant is equipped with an internal storage area for cast iron ingots, cast iron scrap and automotive sheet metal, picked by an electromagnet to feed the furnaces during the spheroidal graphite iron melting process.

The plant’s external landing area is regularly used to store cast iron ingots from various certified suppliers, which, similarly to ferroalloys, alloys and ancillary materials, are subject to radiometric control. The availability and efficient management of this “raw material park” ensures we always have immediate access to the ferrous material we need to feed the production lines, without running the risk of falling short.

In addition to the raw materials park, we also internally manage all the alloying elements (from iron-silicon to nickel and molybdenum) necessary to produce all grades of spheroidal graphite iron (including solid-solution strengthened ductile iron – high silicon ductile iron) and austempered ductile iron (ADI).

The sand plant feeds the moulding line for green sand mould castings

The Zanardi Fonderie sand plant continuously feeds the moulding line, where pieces are moulded in green sand bonded with bentonite (an inorganic compound).

The green sand is obtained by mixing:

 

  • Generally siliceous sand;
  • Bentonite;
  • Real additives, the most common of which is mineral black;
  • Water.

The quality of the sand, essential in obtaining excellent results in terms of the quality of manufactured castings, is monitored daily by way of several different tests to measure:

 

  • Moisture content;
  • Compatibility;
  • Cohesion;
  • Permeability;
  • Green tensile strength;
  • Wet tensile strength;
  • Weight.

A controlled and efficient warehouse for the safe storage of client models

Zanardi Fonderie has a designated area in its production plant in Minerbe (Verona) for the storage of all client models and equipment (casting plates and relative core boxes). The orderly organisation of the models warehouse guarantees the rapid and flexible management of production orders. Before being used in the production of cast iron castings, the models are checked by our staff, who examine the surface layer and any wear, performing routine maintenance if necessary.

In accordance with the product requirements and production volumes requested by the client, foundry models can be developed in:

 

  • Aluminium;
  • Resin;
  • Wood (typically used for prototypes and small series).