JIS G 3321 discusses the Hot-dip 55 % aluminium-zinc alloy-coated steel sheet and coil in Japanese standard. It specifies the different shapes and dimensions of corrugated sheets. The corresponding American standard is ASTM a792.
What is JIS G 3321?
JIS G 3321 specifies the mechanical criteria for sheets and coils. It includes bendability, tensile strength, elongation, and yield point or proof stress. The sheets undergo the hot-dip bath method that contains 55% aluminum, 1.6% silicon, and zinc. They make the steel sheets durable and strong.
The Standard also sets the base metal thickness of the sheets and coils. It also prescribes manufacturing processes that include strain aging, painting, and oiling.
The JIS G 3321 also notes the chemical analysis for sheets and coils that manufacturers have to do. Makers will do the heat analysis to ensure compliance. Buyers will take charge of product analysis for verification.
JIS G 3321 requires that coating mass undergo testing. It also specifies that sheets should have at least a coating mass on both sides.
Based on the previous testing, it also sets the guide on the average coatings that sheets should have. The number of coatings may also depend on the agreement of buyers and makers.
The Standard notes the standard finishes for the coating. The Normal Spangle is when the coating has a glittery finish. The Skin Pass, where the surface is smooth, as requested by the purchaser.
The JIS G 3321 also discusses the Coating Mass, mentioning the minimum requirements.
Makers should follow the requirements under the JIS G 3321. It helps makers of steel sheets and coils produce quality output.