This specification covers electrical-fusion-welded steel pipe for high-pressure service at moderate temperatures. Heat treatment may or may not be required to attain the desired properties or to comply with applicable code requirements. An analysis of each mill heat of plate material shall be made, also, an analysis of the finished deposited weld material from each 500 ft or fraction thereof shall be made. The mechanical test requirements includes one tension test specimen to represent each lot of finished pipe, and one transverse-guided-weld-bend test (two specimens) to represent each lot of finished pipe. Also, radiographic examination shall be made on the full length of each weld.

1.1 This specification2 covers steel pipe: electric-fusion-welded with filler metal added, fabricated from pressure-vessel quality plate of any of several analyses and strength levels and suitable for high-pressure service at moderate temperatures. Heat treatment may or may not be required to attain the desired properties or to comply with applicable code requirements. Supplementary requirements are provided for use when additional testing or examination is desired.

1.2 The specification nominally covers pipe 16 in. [400 mm] in outside diameter or larger with wall thicknesses up to 3 in. [75 mm], inclusive. Pipe having other dimensions may be furnished provided it complies with all other requirements of this specification.

1.3 Several grades and classes of pipe are provided.

1.3.1 Grade designates the type of plate used.

1.3.2 Class designates the type of heat treatment performed during manufacture of the pipe, whether the weld is radiographically examined, and whether the pipe has been pressure tested as listed in 1.3.3.

1.3.3 Class designations are as follows (Note 1):

Class

Heat Treatment on Pipe

Radiography,
see Section

Pressure Test,
see Section

10

none

   none

   none

11

none

   9

   none

12

none

   9

   8.3

13

none

   none

   8.3

20

stress relieved, see 5.3.1

   none

   none

21

stress relieved, see 5.3.1

   9

   none

22

stress relieved, see 5.3.1

   9

   8.3

23

stress relieved, see 5.3.1

   none

   8.3

30

normalized, see 5.3.2

   none

   none

31

normalized, see 5.3.2

   9

   none

32

normalized, see 5.3.2

   9

   8.3

33

normalized, see 5.3.2

   none

   8.3

40

normalized and tempered, see 5.3.3

   none

   none

41

normalized and tempered, see 5.3.3

   9

   none

42

normalized and tempered, see 5.3.3

   9

   8.3

43

normalized and tempered, see 5.3.3

   none

   8.3

50

quenched and tempered, see 5.3.4

   none

   none

51

quenched and tempered, see 5.3.4

   9

   none

52

quenched and tempered, see 5.3.4

   9

   8.3

53

quenched and tempered, see 5.3.4

   none

   8.3

Note 1: Selection of materials should be made with attention to temperature of service. For such guidance, Specification A20/A20M may be consulted.

1.4 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. The inch-pound units shall apply unless the “M” designation of this specification is specified in the order.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.