When you buy round bar for pressure, marine or oil and gas work, the type of material certificate matters as much as the grade. EN 10204 defines four types; 3.1 and 3.2 are the ones used for traceable, tested material.
| Type | Document | Validated by |
|---|---|---|
| 2.1 | Declaration of compliance with the order | Manufacturer. No test results |
| 2.2 | Test report | Manufacturer. Non-specific inspection results |
| 3.1 | Inspection certificate | Manufacturer's authorized inspection representative, independent of production |
| 3.2 | Inspection certificate | Manufacturer's authorized representative and the purchaser's representative or an inspector named in official regulations |
A 3.1 certificate reports the results of tests carried out on the delivered material. It normally shows the heat number, grade and specification (for example ASTM A276), chemical analysis, mechanical test results, heat treatment condition, dimensions, and the validating signature or stamp. The heat number links the certificate to the marking on the bar.
A 3.2 certificate carries the same test information, but is also validated by a second, independent party: the purchaser's representative or an inspector designated under official regulations. In practice this is often a third-party inspection agency attending the tests, and the process adds time and cost.
3.1 is the standard requirement for most industrial and export orders and is what we supply with every shipment. 3.2 is typically required by pressure-equipment regulations, classification societies and some oil and gas or nuclear specifications. Check your purchase specification or inspection and test plan, and tell us at enquiry stage if you need 3.2, so we can arrange the inspector and allow for the lead time.
Confirm that the heat number matches the bar markings, that the grade and standard match your order, that chemistry and mechanical results sit inside the specified limits, and that the heat treatment condition is correct. Requests for positive material identification (PMI) on the delivered bars add a further check.
