By the Decree of the USSR State Committee for Standards of November 25, 1985 No. 3693, the date of introduction was set
01.01.87
The limitation of the validity period was lifted by the Resolution of the State Standard dated 14.08.91 No. 1353
This standard applies to steel welded longitudinal and spiral-seam pipes with a diameter of 159-820 mm used for the construction of trunk gas and oil pipelines, oil product pipelines, process and field pipelines.
1. BASIC PARAMETERS AND DIMENSIONS
1.1. There are three types of pipes:
1 - longitudinal seam with a diameter of 159-426 mm, made by resistance welding with high frequency currents;
2 - spiral seam with a diameter of 159-820 mm, made by electric arc welding;
3 - longitudinal seam with a diameter of 530-820 mm, made by electric arc welding.
1.2. Depending on the mechanical properties of the pipe, strength classes are manufactured: K 34, K 38, K 42, K 50, K 52, K 55, K 60.
1.3. The dimensions of the pipes must correspond to those given in table. 1.
1.4. Pipes are manufactured in lengths from 10.6 to 11.6 m.Up to January 1, 1989, it is allowed to produce up to 15% (by mass) of type 3 pipes (hot-directed) and up to 3% (by mass) of type 1 pipes with a length of at least 5 m . For pipes of types 1, 2 and expanded type 3, it is allowed to make up to 10% (by mass) of pipes with a length of at least 8 m.
Table 1
Notes: 1. The theoretical mass is determined by the nominal dimensions (without taking into account the reinforcement of the weld) with a steel density of 7.85 g /cm 3 . 2. In the manufacture of pipes of type 2, the theoretical mass increases due to the reinforcement of the seam by 1.5%, pipes of type 3 by 1%. At the request of the consumer, it is allowed to manufacture pipes with an intermediate wall thickness within the table. 1 at 0.1 mm intervals.
1.5. Limit deviations for the outer diameter of the pipe body must comply with Table 2.
At the request of the consumer, the maximum deviations for the outer diameter of the body of pipes of type 2 with a diameter of 159-377 mm must correspond to those given in table. 3.
Table 2
Table 3
1.6. Maximum deviations for the outer diameter of the ends of pipes of type 1 must correspond to table. 2, type 2 with a diameter of 159 - 377 mm - tab. 2 and 3.
1.7. Limit deviations in the outer diameter of the ends of pipes of type 2 with a diameter of 530 mm and more and type 3 (expanded) should not exceed ± 2.0 mm for normal manufacturing accuracy and ± 1.6 mm for increased manufacturing accuracy.
Until January 1, 1990, the maximum deviations in the outer diameter of the ends of pipes of type 3 (hot-directed) should not exceed ± 2.5 mm.
1.8. Maximum deviations in pipe wall thickness must correspond to metal thickness tolerances provided for by GOST 19903-74 for the maximum width of sheet and coil steel.
1.9. The ovality of the ends of the pipes should not deduce their dimensions beyond the maximum deviations given in table. 2 - for pipes of type 1, and in table. 2 and 3 - for pipes type 2 with a diameter of 159-377 mm.
The ovality of the ends of type 2 pipes with a diameter of 530 mm and more and type 3 pipes should not exceed 1% of the nominal outer diameter.
1.10. The curvature of type 1 pipes, excluding the section of the transverse seam, should not exceed 1.5 mm per 1 m of length, at the request of the consumer - 1 mm per 1 m of length.
The total curvature of pipes of all types should not exceed 0.2% of the pipe length. At the request of the consumer, the total curvature of type 2 pipes with a diameter of 530 mm and more should not exceed 0.1%, other pipes - 0.15% of the pipe length.
1.11. The height of reinforcement of all external seams of pipes of types 2 and 3 must be:
0.5-2.5 mm - for pipes with a wall thickness of less than 10 mm,
0.5-3.0 mm - for pipes with a wall thickness of 10 mm or more.
The height of reinforcement of internal seams must be at least 0.5 mm. On the inner seam, a saddle or separate indentations are allowed up to the level of the base metal.
At the ends of expanded pipes of type 3, as well as heat-strengthened pipes of type 2, at a length of at least 150 mm, the reinforcement of the inner seam must be removed to a height of no more than 0.5 mm (excluding edge displacement). At the same time, it is allowed to manufacture up to 7% of pipes from a batch (from which samples were taken for mechanical tests) with non-removable reinforcement of internal seams. Expansion of pipes with unremoved weld seam reinforcement is not allowed.
1.12. The height of the remainder of the outer burr on type 1 pipes must not exceed 1 mm. The inner burr is not removed.
1.13. In a welded joint of type 2 pipes, a relative displacement of the edges in height by up to 15% of the nominal wall thickness is allowed, for pipes of types 1 and 3 - up to 10%.
At the request of the consumer, for pipes of type 2 with a diameter of 530 mm and more, the deviation from the theoretical circle in the area of the spiral seam along the ends of the pipe on an arc of a circle with a length of at least 100 mm should not exceed 1.5 mm.
1.14 Pipe ends should be cut at right angles. Maximum deviations from a right angle (oblique cut) must correspond to table. 4
