Heavy plates (quarto plates) are hot-rolled steel plates with a thickness of 3 mm or more according to DIN EN 10079. Thin plates are plates with a thickness of less than 3 mm.

Heavy plates can be up to 400 mm thick.

DIN EN 10029 describes the deviation limits and geometric tolerances for heavy-plate. The deviation limits are divided into 4 classes:

A         Lower deviation limit depends on the nominal thickness

B         -0.3 mm is the constant lower deviation limit

C         0 is the lower deviation limit

D         Depending on the nominal thickness, the deviation limits are distributed symmetrically to the nominal value.

The delivery conditions for the surface quality of heavy plate are defined in DIN EN 10163-2.


About our heavy plates

Heavy steel plates are made of non-alloy and alloy steels.

UnionStahl specialises in the distribution of heavy-plates. In addition to steel sheets, our customers can purchase flame-cut parts (cut using oxy-fuel, plasma or laser) up to finished machined components ready for installation. We are a full-range supplier, stocking heavy plates in various non-alloy and alloy steel grades, such as structural steel, pressure vessel steel, offshore steel, wear-resistant steel, high-strength steel, case-hardened steel and quenched and tempered steel.

Thanks to our extensive delivery programme of heavy steel plates and flame-cutting and machining options, we are a reliable supplier for the steel construction, tank construction, apparatus engineering, wind energy, shipbuilding, offshore, railway engineering, pipeline construction, mechanical engineering, construction machinery, crane construction, agricultural machinery, mining and toolmaking sectors.

In addition to heavy steel plates, our focus is on the sale of strips.



Heavy steel plates are particularly popular with design engineers, mainly because of their versatility. Our customers come from a wide variety of industries in which finished rolled products play a significant role. They include power plants and shipbuilding, mechanical and plant engineering as well as container and crane construction. Manufacturing heavy construction vehicles would also hardly be possible without heavy steel plates.