PRODUCTION PROCESS

The production process starts with the selection of the best raw materials, maintaining quality at the highest levels throughout profile processing. Expertise, know-how and innovation have led to the production of over 6200 different steel profiles. The raw material consists of rolled, forged round bars or bars obtained by continuous casting, which are purchased either raw or peeled. Siderval has an automatic steel peeling plant with an annual production capacity of 42,000 t, enough to meet its own production requirements and satisfy any external processing demands. Production diameters are: 155, 180, 220, 260 and 270 mm. The raw material purchased complies with European and internationally recognised quality standards and certifications, according to specific customer requirements.

The production process continues with the cutting and radiusing of the steel bars. This is achieved with an automatic plant equipped with band saws, which guarantees highly accurate cutting without compromising on quality. After cutting, the pieces are engraved with an ID number to ensure they can be traced throughout the production process. The pieces are then placed in special boxes marked with a label showing information about the content. If a customer requests hollow profiles, the billets are pierced automatically using a system for this specific purpose. The advanced technology used guarantees extremely accurate and efficient material traceability and production of hollow profiles.

Hot extrusion is an innovative technology used for the production of special profiles in carbon steel, stainless steel, special alloys and titanium.
The extrusion process enables the production of solid or hollow bars with fixed sections and complex geometries, without the need for mechanical machining. Hot extrusion technology is at the core of Siderval’s production process.
Siderval has a 2400 t horizontal hydraulic press for the extrusion of billets that are previously heated in four induction furnaces.
This process takes place in a hollow cylinder called container. The billet is inserted in the container and, using a shaped die, the pressure applied by the press forces the billet through the die resulting in an extruded special profile. Siderval can produce up to 12-metre-long extruded bars, with solid or hollow sections and with a circumscribing circle diameter of up to 210 mm diameter. It uses a wide range of steel grades, including carbon steels, alloy steels, stainless steels, nickel-based alloys and titanium alloys.

The finishing department is equipped with stretching and straightening machines for the production of straight bars within required template tolerances.
In fact, when the bars exit the press, they are bent and twisted.
During this processing stage, the bars are stretched until reaching a first level of straightening, then they are cut to length.
Cutting is usually done with a cut-off machine, but if accurate length tolerances are required, then a band saw is used.
Siderval’s priority is to offer high quality extruded bars, drawing on advanced finishing techniques and thorough processing to meet customer requirements.

Steel heat treatment can generally be divided into three stages:

• Oven heating
• Maintaining a set temperature for a certain length of time
• Cooling to specific procedures

Siderval’s heat treatment systems perform the most common types of treatment, but we also use highly experienced suppliers for more complex treatments.
Heat treatment changes the hardness, strength, toughness and machinability of steel. Our two in-house furnaces offer treatments such as annealing, normalising and stress relieving, and where necessary, we use our own qualified suppliers.

The main packaging methods used are: bundles, PVC-wrapped bundles, pallets, wooden crates and containers.

Bundle packaging
The bars are gathered, held together and secured by metal strapping. A label is attached to each bundle showing: supplier, batch number, casting number, type of steel used and dimensions.

PVC-wrapped bundle packaging
The bundles held together by straps are additionally wrapped in PVC film for greater protection.

Pallet packaging
When short bars need to be packaged, they can be placed on pallets and wrapped using straps. If necessary, a plastic protection film can be added.

Packaging with wooden crates
This type of packaging is chosen for shipments by air and often for shipments by sea. Wooden crates are appropriately fumigated and receive phytosanitary treatment in compliance with ISPM No. 15 – FAO requirements.

Containers
Shipping by container is preferred when large quantities of goods need to be shipped. The bars inside the container are packaged using PVC film or wooden crates.