Cast rolls and rings
Qualities and dimensions
We supply cast rolls and rings for steel rolling mills in all common qualities and dimensions.
Our customers are bar steel and wire rod manufacturers as well as strip and section rolling mills. We are able to supply two types of cast rolls:
1. Static Cast
2. Centrifugal Cast
Our partner in Italy boasts 3 electric induction melting furnaces for cast preparation: one furnace with 6 tons and two furnaces with 15 tons capacity as well as gas furnaces for heat treatment. All furnaces are automatically controlled by PLC.
Further information
Only raw materials and alloys of the highest quality are used to feed our melting furnaces.
We also have equipment for processing sand and machines for molding bottles. The total capacity is 8,000 tons/year. Our production in Italy features two workshops: one of them is directly connected to the foundry by roller conveyors in order to transport the raw castings to the machining department. Our two workshops are equipped with horizontal, vertical and numerically controlled lathes, drilling, milling and grinding machines, including everything necessary to supply customers with ready-to-use rollers.
The equipment enables the production of parts up to a diameter of 1.400 mm. Our laboratory features a spectrometer for real-time chemical analysis of samples taken from the furnaces during the preparation of the melt, as well as samples taken from the rolls for production control.
The spectrophotometer is used for special analyses and for the evaluation of ferroalloys; our casting sands are also checked using special equipment. Metallographic examinations are carried out on the materials produced, using an optical microscope so that the structures can be examined in detail.
The finished rollers are then forwarded from the workshop to the inspection and dispatch department.
The final inspection includes: dimensional control, hardness and ultrasonic testing and any other control required by the customer. The roll number assigned to each roll at the beginning of the production cycle is now stamped onto the finished item, thereby allowing quick and clear identification of the product. Painting and packaging are the final steps of the production cycle, which is completed with shipping.
Specification:
The presence of free graphite flakes in the working layer distinguishes indefinite cast iron rolls from cast iron rolls with regular cooling. Free graphite improves the elastic properties of the material, reduces the effects of specific rolling stresses and favors heat exchange by increasing resistance to thermal fatigue. The microstructure also consists of cementite, which increases wear resistance; it is present in a pearlitic or bainitic-martensitic matrix. Rolls can be supplied as monobloc or composite material. If high hardness is required in the working layer, in combination with a highly resistant core metal, the use of composite rolls (double cast) is recommended.
Application:
Indefinite cast rolls are mainly used as roughing and finishing rolls for bars, flat, light and medium profiles.
Specification:
The microstructure of chilled cast iron rolls consists of a non-continuous network of carbides in a pearlitic or bainitic-martensitic matrix. Thanks to their high carbide content, these rolls feature excellent wear resistance, while their resistance to thermal fatigue is reduced by the absence of free graphite. These rolls can be supplied as monobloc or composite material. For high hardness, the use of composite rolls is recommended, thereby ensuring optimum properties in the working layer and core.
Application:
Clear Chill Cast Rolls are used for intermediate, roughing and finishing stands of open and continuous rolling mills, for wire rod as well as for roughing and finishing stands for narrow strip. They are also used as guide rolls.
Specification:
After treatment with magnesium, the graphite contained in nodular cast iron precipitates in the form of spheroids. Nodular cast iron has similar mechanical properties to cast steel, while its wear resistance is typical of alloyed cast iron. The materials are classified according to their type of matrix: ferritic-pearlitic, pearlitic and acicular.
Application:
These rolls are mainly used in wire, bar, light, medium and heavy section rolling mills. The ferritic-pearlitic matrix is used for roughing stands in which high thermal stresses can occur, while pearlitic types are used for roughing and preparation stands; the needle-shaped matrix is more commonly used in pre-finishing and finishing stands.
Specification:
Steel-based rolls feature a carbon content of between 1.50 and 2.10 % and are Cr-Ni-Mo-alloyed. The chemical analysis and specific heat treatments provide the material the high mechanical properties typical of steel and the wear resistance characteristic of cast iron. The hardness is constant throughout the entire working layer. The microstructure consists of a pearlitic matrix and small carbides. Rolls made of graphitic steel boast better thermal conductivity thanks to the presence of graphite beads.
Application:
Steel-based rolls are used for roughing, preparation, pre-finishing and finishing of stands for light, medium and heavy profiles where high mechanical properties are required under difficult rolling conditions. Rolls made of graphitic steel are particularly suitable for environments with high thermal loads.
