1. The approval procedure for batch acceptance of
straight seam steel pipes should meet the corresponding product standards.
2. Straight seam steel pipes should meet the corresponding product standards, including inspection items, sampling quantity, sampling location, and test methods. With the buyer's consent, hot-rolled seamless steel pipes can be sampled in batches according to the number of rolled pipes.
3. If there is an item that does not meet the requirements of the product standard, the unqualified item should be selected, and double samples should be taken from the same batch of straight seam steel pipes to review the unqualified products. If the results of the re-inspection do not meet the standards, the batch of straight seam steel pipes shall not leave the factory.
4. Straight seam steel pipes that do not meet the standards (including items that do not meet the standards and are not allowed to be re-checked) should be submitted to the supplier for acceptance at one time, or a new batch of reheat treatment should be accepted (reheat treatment should not exceed two times).
5. If there is no special regulation in the product standard, the chemical composition of the straight seam steel pipe will be accepted according to the melting composition.
