Pre-Shipment Inspection for Carbon Steel: Complete Quality Guide

2.2 Chemical Composition Verification

Chemical analysis confirms that the steel meets the specified grade requirements:

For on-site PSI, portable OES or XRF is typically used. The inspector checks C, Mn, Si, P, S, and any specified alloying elements against the mill test certificate and the applicable standard.

2.3 Mechanical Property Testing

Mechanical testing is usually performed at an accredited laboratory using samples taken during the inspection:

• Tensile test (ASTM A370 / EN ISO 6892-1): Measures yield strength, tensile strength, and elongation. One test per heat (or per lot, as specified).
• Impact test (ASTM E23 / EN ISO 148-1): Charpy V-notch at specified temperature (20°C, 0°C, or -20°C depending on grade). Three specimens per test.
• Hardness test (ASTM E10 Brinell / E18 Rockwell / E92 Vickers): Quick verification of heat treatment condition. 3-5 readings per piece.
• Bend test (ASTM E290): For plates and bars, verifies ductility. One test per lot.

2.4 Non-Destructive Testing (NDT)

For critical applications, NDT methods supplement visual inspection:

3. Sampling Plans: How Many Pieces to Inspect

The number of pieces to inspect depends on the lot size and the acceptable quality level (AQL). The most commonly used standard is ISO 2859-1 (equivalent to ANSI/ASQ Z1.4):

For steel products, AQL 2.5 is standard for general defects (surface marks, minor dimensional deviations), while AQL 1.0 or 0.65 is used for critical defects (wrong grade, insufficient mechanical properties). Buyers should specify the AQL level in the purchase contract.

4. Documentation Review

A critical part of PSI is verifying that all documentation is complete, accurate, and consistent with the physical products:

Essential Documents to Verify

• Mill Test Certificate (MTC): EN 10204 3.1 or 3.2, with actual heat chemistry and mechanical test results. Cross-check heat numbers on the MTC with markings on the steel.
• Heat number traceability: Each piece must be marked with a heat number that traces back to the MTC. Verify 100% of sampled pieces.
• Packing list: Check quantities, dimensions, and weights against physical count and measurements.
• Certificate of Origin (COO): Required for preferential tariff treatment and customs clearance.
• Material test reports: For special applications (pressure vessels, offshore), verify additional test reports (e.g., ultrasonic test certificates per EN 10160).
• Commercial invoice: Ensure product descriptions, grades, and quantities match the purchase order.

5. Choosing a Third-Party Inspection Agency

Several internationally recognized inspection firms specialize in steel and metals:

When selecting an agency, consider: (1) their experience with the specific steel product type, (2) local presence near the supplier’s facility to minimize travel costs, (3) accreditation (ISO 17020 for inspection bodies), and (4) report format and digital access.

6. Inspection Report: What to Expect

A professional PSI report should include the following sections:

• Inspection summary: Pass/fail determination, key findings, and recommendations.
• Product identification: Product type, grade, dimensions, heat numbers, and quantities inspected.
• Visual inspection results: Photographs of representative pieces, defects found, and packaging condition.
• Dimensional measurement data: Tabulated measurements with tolerances and pass/fail status.
• Chemical analysis results (if performed): Element-by-element comparison with specification limits.
• Mechanical test results (if performed): Yield, tensile, elongation, hardness, impact values vs. requirements.
• NDT results (if performed): Defect maps, signal traces, and accept/reject classification.
• Document review: MTC verification, packing list reconciliation, and certificate validation.
• Non-conformities: Detailed description of each deviation, severity classification, and recommended corrective action.

Frequently Asked Questions

When should the pre-shipment inspection be scheduled?

The PSI should be scheduled when at least 80% of the order is produced and packed, and the remaining 20% is in process. This allows the inspector to verify the majority of the goods while giving the supplier time to address any issues before shipment. For large orders, a final random inspection (FRI) at 100% completion is recommended.

Who pays for the pre-shipment inspection?

By default, the buyer pays for PSI. However, if the inspection reveals material non-conformities, the contract should specify that the supplier bears the cost of re-inspection after corrective action. Some contracts include a “passed inspection” clause where the seller pays for the first inspection and the buyer pays only if the goods pass.

Can the inspection be done at the port instead of the factory?

Yes, but it is not recommended. Port inspections occur after loading, making it impossible to verify individual piece markings, access the full lot for sampling, or address non-conformities before shipment. Factory inspections are always preferred because they provide the opportunity for corrective action before goods leave the supplier’s premises.

What happens if the inspection fails?

If critical defects are found, the buyer should reject the lot and require the supplier to rework or replace the non-conforming pieces. For minor defects, the buyer may accept the lot with a price concession or require selective sorting. The purchase contract should specify the rejection criteria and the supplier’s obligations in case of failure.

Is pre-shipment inspection mandatory for steel imports?

PSI is not legally mandatory for most steel imports, but it may be required by the buyer’s bank (especially under Letter of Credit terms), by project specifications (e.g., oil & gas projects require independent inspection), or by certain countries’ import regulations. Regardless of mandates, PSI is strongly recommended for all steel imports exceeding $10,000 in value.

Conclusion

Pre-shipment inspection is an indispensable quality assurance step for carbon steel imports. By verifying chemistry, mechanical properties, dimensions, surface quality, and documentation before shipment, buyers can avoid the costly consequences of receiving non-conforming material. The investment in a professional PSI — typically 0.1-0.5% of the order value — pays for itself many times over by preventing rejected shipments, project delays, and liability claims. Work with a reputable inspection agency, specify clear acceptance criteria in your purchase contract, and always insist on a factory inspection before goods are loaded.

Need a pre-shipment inspection for your carbon steel order? Huaxia-Steel works with all major inspection agencies and provides full factory access for PSI. We ensure every shipment meets your specifications before it leaves our facility. Contact us to discuss your quality requirements.