IS 13620:1993 is the Indian Standard (BIS) for continuous hot-dip zinc/zinc-alloy coated steel sheet and strip - specification. This standard specifies the requirements for continuous hot-dip zinc or zinc-alloy coated carbon steel sheets and strips. It details base metal grades, coating mass, dimensional tolerances, mechanical properties, and testing methods for materials used in construction, automotive, appliances, and general engineering.
Specifies the requirements for continuously hot-dip zinc or zinc-alloy coated steel sheet and strip.
Overview
- Status
- Current
- Usage level
- Frequently Used
- Domain
- Materials Science — Aluminium and Non-Ferrous Metals
- Type
- Specification
Also on InfraLens for IS 13620
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
Practical Notes
! The coating designation (e.g., Z120, Z275) refers to the total minimum mass of zinc in g/m² on both sides of the sheet, not the thickness.
! Always specify the base steel grade (e.g., CQ, DQ, DDQ, SQ) along with the coating mass, as this dictates the material's formability and strength.
! Surface finish (e.g., regular spangle, minimized spangle, zero spangle) and condition (e.g., skin passed, oiled) must be specified based on the end-use, especially for painting or aesthetic applications.
Frequently referenced clauses
steelzinczinc-alloycoated steel
International Equivalents
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International Comparison — Coming Soon
We're adding equivalent international standards for this code.
Key Values7
Quick Reference Values
Minimum zinc coating mass (Z120)120 g/m² (total both sides)
Minimum zinc coating mass (Z275)275 g/m² (total both sides)
Minimum elongation for Commercial Quality (CQ) grade (t ≥ 0.6 mm)20%
Thickness tolerance for sheets (t < 0.60 mm)±0.05 mm
Thickness tolerance for sheets (0.60 ≤ t < 1.00 mm)±0.06 mm
Maximum Sulphur content in base metal0.040 %
Maximum Phosphorus content in base metal0.040 %
Tables & Referenced Sections
Key Tables
Table 1 - Chemical Composition of Base Metal
Table 2 - Mass of Coating
Table 3 - Mechanical Properties for Various Grades of Base Metal
Table 4 - Tolerances on Thickness
Table 5 - Tolerances on Width
Key Clauses
Clause 3 - Material and Manufacture
Clause 4 - Grades
Clause 5 - Coating
Clause 8 - Dimensions and Tolerances
Clause 10 - Mechanical Properties
Clause 13 - Sampling and Criteria for Conformity
Frequently Asked Questions4
What are the common steel grades covered in IS 13620?+
The standard covers Commercial Quality (CQ), Drawing Quality (DQ), Deep Drawing Quality (DDQ), and Structural Quality (SQ) (Clause 4.1).
What does the coating designation 'Z275' signify?+
It signifies a minimum total zinc coating mass of 275 g/m² on both surfaces of the sheet (Table 2).
What is the base material for this coated steel?+
The base metal is typically cold rolled low carbon steel sheet and strip, often conforming to IS 513 (Clause 3.1).
Are there specified mechanical properties for Commercial Quality (CQ) grade?+
No, CQ grade is not required to have specific tensile or yield properties, but a bend test and minimum elongation are specified (Table 3).
QA/QC Inspection Templates
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QA/QC templates coming soon for this code.