SD Bars & Coils


SIDENOR, one of Greece’s leading steel companies, with more than 50 years’ experience in the production of steel products, was the first to introduce the new weldable High Strength SD Class C Steel B500C - ELOT 1421 in Greece.

SD Class C Concrete Reinforcing Steel is available in diameters of 8, 10, 12, 14, 16, 18, 20, 22, 25, 28, 32 and 40 mm, in straight bars of 12 and 14 metres, and in bundles weighing about 2 tonnes.

SD Class C Steel is also available in standard coils (in diametres of 6, 8, 10, 12 and 14 mm), as well as in spooled coils (in diameters of 8, 10 and 12 mm).


    The mechanical properties of SD Class C Steel are achieved with the use of the suitable chemical composition and special heat treatment (see Figure) during production. The chemical composition is characterised by the increased content of the elements that give steel its “natural hardness”.

    With the special heat treatment, the surface of the steel is submitted to hardening, which gives steel high strength, while its interior part is cooled less intensely, giving it high ductility.


    Constantly increasing requirements for earthquake-resistant constructions require the use of high ductility steels. This led the Greek Earthquake Planning and Protection Organisation (OASP) to propose for the first time steels which are characterised not only by their strength but also by their high ductility, in ductility classes Α and C (where C is the most ductile steel). Class C has adopted by the committee charged with drawing up the new national standard, and is specified in ELOT’s new 1421 - B500C standard.

    The ductility of steel (its ability to absorb energy) is the most critical condition affecting the ability of a reinforced concrete construction to develop plasticity. On the stress-strain diagram (σ-ε) obtained from the tensile test, the plastic energy absorbed by steel is represented by the area covered by the shaded part of the diagram.

    Increasing ductility means maximising this area, which is achieved through high values for Strain (elongation) (εu) and Tensile Strength/Yield Strength ratio (ft/fy).

    In current standards, ductility is defined by a series of parameters such as:

    • Elongation at Maximum Load (Agt)
    • The ratio between the Ultimate Tensile Strength of the steel and its Yield Strength (ft/fy)
    • The ratio between the actual and the nominal Yield Strengths (fy act/fy nom).

    In its quest for high quality and innovation, SIDENOR has started production of high ductility SD Class C Steel (ELOT 1421 - B500C).

    The following table lists the mechanical properties of  SD Class C Steel in terms of the most important current standards and regulations on steels.

    (The requirements of the standards are stated in typical values)

    Mechanical Characteristics of SD Steel
    Mechanical Characteristics EKOS 2000** ΕΛΟΤ 1421 - B500C STANDARD SIDENOR SD Grade C (B500C)
    fy(N/mm²) >=500 >=500 >=500 560*
    ft(N/mm²) >=550 >=550 >=575 665*
    Agt(%) >=7 >=7,5 >=8 10*
    ft/fy >=1,10 >=1,15 >=1,15 1,18*
    fy act/ fy nom <=1,30 <=1,25 <=1,20 1,12*

    * Mean value
    ** EKOS 2000: Current Greek Regulation for Concrete Reinforcement

    SIDENOR’s SD Class C Steel exceeds the current ductility requirements of even the most stringent standards and regulations.


    SIDENOR’s SD Class C Steel (B500C (ELOT 1421)) has two longitudinal ribs and additional transverse ribs with alternating direction on two sides. On one side there is the mark indicating the production site (8/14 for the plant in Thessaloniki and 8/24 for SOVEL plant in Almiros, Magnesia). Moreover, SIDENOR’s SD Class C Steel bears the clear “SD” mark, for easier identification at all stages of its distribution, storage and use.


    TYPE: Hot-rolled concrete reinforcing steel, in straight bars and coils

    Ribbed, weldable, High Tensile SD Steel, Class Β500C
    Produced according to ELOT 1421


     Straight bars. Diameter from Ø8 to Ø40mm with SD marking up to Ø28mm
    Coils. Bar diameter from Ø6 to Ø16mm with SD marking


    Length of straight bars: 12 or 14m, with tolerance -0 / +100mm


    Bundles of straight bars. Weight: approximately 2.00MT per bundle
    Coils. Weight: approximately 1.25-1.45MT per coil or spooled coils weight up to 4.50MT per coil


    Customer requirements for other lengths, as well as other recognised industrial standards, can be met upon request.




    8 50,3 0,395 ± 6.0
    10 78,5 0,617 ± 4.5
    12 113,0 0,888 ± 4.5
    14 154,0 1,210 ± 4.5
    16 201,0 1,580 ± 4.5
    18 254,0 2,000 ± 4.5
    20 314,0 2,470 ± 4.5
    22 380,0 2,980 ± 4.5
    25 491,0 3,850 ± 4.5
    28 616,0 4,830 ± 4.5
    32 804,0 6,310 ± 4.5
    40 1.257,0 9,860 ± 4.5


    INTERNAL DIAMETER (m) 0,95 0,75
    EXTERNAL DIAMETER (m) 1,15-1,20 0,90-1,00
    HEIGHT (m) 1,15-1,20 0,75



    For the production of Concrete Reinforcing Steel, SIDENOR has been certified by the following certification bodies: Greek “ELOT”, German steel certifying body “Prufstelle fur Betonstahl (grade BST500s according to DIN 488), French “AFCAB” (grade FEE500-3, according to NFA 35-016) as well as the Italian certification body (grade FEB44K according to D.M. 09.01.1996).

  • SD Steel