What do the grades O, D, DD, EDD mean?

O = Ordinary (commercial forming), D = Drawing quality, DD = Deep Drawing quality, EDD = Extra Deep Drawing quality. Higher grades have lower yield strength and higher elongation for better formability.

What is the difference between IS 513 and IS 1079?

IS 513 covers cold rolled (CR) steel sheets. IS 1079 covers hot rolled (HR) steel sheets. CR sheets are thinner, have better surface finish, and tighter dimensional tolerances.

IS 513:2018 — Cold Rolled Low Carbon Steel Sheets and Strips

IS 513 : 2018

Cold Rolled Low Carbon Steel Sheets and Strips

ASTM A1008/A1008M · EN 10130

CurrentFrequently UsedSpecificationMaterials Science · Steel and Reinforcement

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Summary

IS 513 specifies cold rolled low carbon steel sheets and strips in 4 grades (O, D, DD, EDD) based on formability. Grade O is for commercial bending, while EDD is for severe deep drawing. Widely used in automotive, appliances, furniture, and HVAC ductwork.

Specification for cold rolled low carbon steel flat products (sheets, strips, and coils) for commercial, drawing, and deep drawing quality applications.

Key Values

Grade O yield strengthMax 280 MPa

Grade D yield strengthMax 240 MPa

Grade DD yield strengthMax 220 MPa

Practical Notes

! Grade D is the most commonly ordered grade for general sheet metal fabrication in India.

! For automotive body panels, specify Grade DD or EDD — Grade O will crack during deep drawing.

! Always check surface finish specification — bright finish (B) vs matte finish (M) affects painting adhesion.

! CR steel rusts quickly without coating — specify galvanized (IS 277) if corrosion is a concern.

Cross-Referenced Codes

IS 1079:2017Hot Rolled Carbon Steel Sheets and Strips

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IS 2062:2011Hot Rolled Medium and High Tensile Structural...

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IS 1852:1985Rolling and Cutting Tolerances for Hot Rolled...

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cold rolledsteel sheetsCR steellow carbondeep drawingsheet metal