Manufacturing process

The ongoing commitment to process innovation has always supported Calvi’s long experience in the steel industry.
Calvi is provided with state-of-the-art machinery and equipment which, combined with the experience of its technical staff, ensure the highly competitive engineering of its manufacturing process across a wide range of products.

HOT ROLLING

After the testing  of incoming material and automatic bar peeling phases, the raw material in cast, rolled or forged steel round bars is hot-rolled: a mechanical processing technique for the plastic forming of steel, which is obtained by passing it through a pair of rigid counter-rotating rollers at very high temperatures.The recent replacement of induction furnaces with new generation furnaces, the increase in heating levels, the presence of rolling stands and the introduction of automatic coiling winders provide the highest levels of safety and productivity for Calvi SpA.
In order to reduce product delivery times and ensure utmost flexibility, there is also an in-house division for building rolling equipment to support the rollers.

rolling installation

PREPARATION

Material heat treatment, phosphating and chemical and mechanical pickling bring the steel’s surface and mechanical properties back to most advantageous levels, thus optimising subsequent operations. Preparation may therefore become necessary as pre-processing or as an intermediate step which is repeated during different stages of the manufacturing process.

preparation installations

COLD DRAWING

Drawing is the main step of profile manufacturing. It involves the preparation of complex geometries with rigorous precision and provides the product with a final section according to the dimensions required by the customer. The feasibility analyses of drawn profiles are processed using sophisticated calculation tools (FEM) that ensure optimisation of the drawing activities during the project study phase.
All the equipment and the many drawing installations for bars and coils are designed in-house and have a 1000 kN drawing capacity.
Once the drawing phase has been completed, other heat, chemical or mechanical treatment or new cold drawing steps may follow; otherwise the profile cutting phase begins.

drawing installations

FINISHING

Calvi SpA also applies its extensive experience in the production of an ever-increasing range of sizes of special profiles, to the finishing phase. Finishing is carried out on straightening lines that have been specially designed to meet even the most challenging requests (max. 0.1 mm/m). Finished material is collected in strapped bundles, in crates or on pallets depending on the customer’s needs or on the need for protection, and ready to be shipped by land, sea or air.

finishing installations