Acceptance steps of submerged arc steel pipe

1. The inspection and inspection of submerged arc steel pipes shall be carried out by the technical supervision bureau of the supplier.

2. The supplier guarantees that the submerged arc steel pipes delivered meet the regulations of the corresponding product standards. The purchaser has the right to conduct inspections in accordance with the corresponding product standards.

3. Submerged arc steel pipes shall be submitted for inspection in batches, and the regulations for group approval shall comply with the regulations of the corresponding product standards.

4. The inspection items, sampling quantity, sampling location and test method of submerged arc steel pipes conform to the regulations of the corresponding product standards. After the demand side agrees, the submerged arc steel pipe can be sampled in batches according to the rolling root array.

5. Test effect of submerged arc steel pipe, when a certain rule does not meet the product standard, the unqualified person should be singled out, and double the number of samples from the same batch of submerged arc steel pipe should be taken for re-inspection of unqualified items .

6. For submerged-arc steel tubes with unqualified retest results (including items with unqualified micro-structure for initial test results and items that are not allowed to be retested), the supplier may submit the inspection one by one; or perform heat treatment from scratch (the number of heat treatments from scratch shall not exceed two times) ), with a new batch of inspections.

7. If the product standard does not make rare rules, the chemical composition of the submerged arc steel pipe shall be checked according to the smelting composition.