1. The technical quality department of the supplier is responsible for the quality inspection and acceptance of straight-seam steel pipes.

2. The supplier shall ensure that the provided straight-seam steel pipe meets the relevant specification requirements. The buyer has the right to inspect and accept it according to relevant quality standards.

3. Straight seam steel pipes must be submitted for inspection in batches and grouped in batches according to relevant product standards.

4. For the inspection items, sampling quantity, sampling location, and inspection method of straight seam steel pipes, please refer to the relevant product specifications. After the hot-rolled seamless steel pipe is approved by the demand side, samples can be taken in batches, one piece for each batch.

5. After testing, if there is one item that is unqualified, the unqualified ones will be eliminated, more than two samples will be randomly selected in the same batch, and the unqualified parts will be re-tested. If the result of the re-inspection is "failure" (the required standard in any one of the tests), the batch of straight-seam steel pipes cannot be delivered. Those who fail the first inspection shall not be re-examined: a. There are white spots in the low-ploidy body; b. Fine tissue.

6. For straight seam steel pipes that have not passed the re-inspection (including the microstructure found during the initial inspection that does not meet the requirements, and cannot be re-inspected), the supplier can send them one by one to the acceptance department for inspection; or reheat (Each heating can not be more than twice), and submit a new batch for acceptance.

7. In the case of no special requirements in the product standard, the chemical composition of the welded pipe shall be inspected according to the smelting composition.