Sampling and retesting standards for steel sheets in metal can manufacturing. Covers sample sizes for sheets/coils, inspection rules, and arbitration testing.

Sampling and Reinspection Rules for Steel Sheets – Metal Can Inspection

1. Sampling

(1) Steel Sheets

Quantity of Packaging Units:
Select 20% of total packaging units in batch (rounded to nearest whole number, min. 4 units). For batches under 4 units, sample every unit.

Number of Samples:

• a. Take 1% of sheets per unit for Grade I tinplate surface inspection
• b. Take 1 sheet per unit for mechanical/tin coating tests (2 sheets for arbitration)
• c. Take 0.5% of sheets per unit for dimensional checks (rounded to whole number)

(2) Coil Sheets

Sampling Unit:
After shearing coils (excluding non-Grade I sheets), sample based on 750m steel strip lengths. User conducts sampling during normal operations with producer supervision. Batches:

• ≤20 units: Sample any 4 units
• >20 units: Sample 4 units per 20-unit block (include remainder)

Number of Samples:

• 1 sheet per unit for tin coating/mechanical tests (2 for arbitration)
• 5 sheets per unit for dimensional/flatness inspection

2. Reinspection

• Surface Quality: Resample 5% of sheets per unit if initial fails Grade I
• Dimensional/Tin Coating/Mechanical Properties: Double sample size per Section (1) if non-conformities found. Batch passes if retest meets standards; fails if any retest defects exist.