1.1 The quality inspection and acceptance of straight seam steel pipes
shall be carried out by the technical quality supervision department of the supplier.
1.2 The supplier must ensure that the delivered straight seam steel pipes meet the requirements of the corresponding product standards. The buyer has the right to inspect and accept according to the corresponding product standards.
1.3 Straight seam steel pipes shall be submitted for acceptance in batches, and the group approval rules shall comply with the provisions of the corresponding product standards.
1.4 The inspection items, sampling quantity, sampling location and test method of straight seam steel pipes shall be in accordance with the provisions of the corresponding product standards.
With the consent of the purchaser, hot-rolled seamless straight seam steel tubes can be sampled in batches according to the rolling root array.
1.5 Straight seam steel pipe test results, when a certain item does not meet the requirements of the product standard, the unqualified person should be singled out, and double the number of samples from the same batch of straight seam steel pipe, any unqualified items should be reviewed Test.
If the re-inspection result (including any index required by the project test) fails, the batch of straight seam steel pipes shall not be delivered.
The following inspection items are not allowed to be re-inspected when the initial inspection fails:
a. There are white spots in the low power organization;
1.6 Straight seam steel tubes with unqualified retest results (including unqualified microstructures and items that are not allowed to be retested) may be submitted for acceptance by each supplier; or re-heat treatment (the number of re-heat treatment shall not exceed two times) To submit for acceptance with a new batch.
1.7 If no special provisions are made in the product standard, the chemical composition of the straight seam steel pipe shall be inspected and accepted according to the smelting composition.
2.1 Straight seam steel pipes with an outer diameter of not less than 36mm and special-shaped straight seam steel pipes with a cross-section circumference of not less than 150mm shall be printed, stamped, rolled, stenciled or pasted at the end of each straight seam steel pipe. The imprint should be clear and obvious and not easy to fall off. The imprint shall include the steel grade, product specifications, production standard number and supplier's imprint or registered trademark. The alloy steel straight seam steel pipe shall be printed with the furnace number and batch number after the steel grade. The joints of geological and petroleum straight seam steel pipes shall be marked with grades or steel grades. The left-hand threaded straight seam steel pipe shall be printed with the word "left" after the standard number. Welded straight seam steel pipe and galvanized welded straight seam steel pipe for low-pressure fluid transportation, electric wire casing, general-purpose electric welded straight seam steel pipe, special-section welded straight seam steel pipe, complicated cross-section seamless straight seam steel pipe, but not every straight The mark is printed on the seamed steel pipe.
2.2 Straight seam steel pipes with an outer diameter of less than 36mm and special-shaped straight seam steel pipes with a cross-sectional circumference of less than 150mm may not be printed.