Page 101 - Pipeline Rules of Thumb Handbook

Table 6
Weld Joint Factor

Weld Joint Factor E

Specification Pipe Mfrd. Pipe Mfrd.
Number Pipe Type (1) Before 1959 After 1958

ASTM A53 Seamless 1.00 1.00
Electric-Resistance-Welded 0.85 (2) 1.00
Furnace Lap-Welded 0.80 0.80
Furnace Butt-Welded 0.60 0.60
ASTM A106 Seamless 1.00 1.00
ASTM A134 Electric-Fusion (Arc)-Welded single or double pass 0.80 0.80
ASTM A135 Electric-Resistance-Welded 0.85 (2) 1.00
ASTM A139 Electric-Fusion-Welded single or double pass 0.80 0.80
ASTM A155 Electric-Fusion-Welded 0.90 1.00
ASTM A381 Electric-Fusion-Welded, Double Submerged Arc-Welded — 1.00
API 5L Seamless 1.00 1.00
Electric-Resistance-Welded 0.85 (2) 1.00
Electric-Flash-Welded 0.85 (2) 1.00
Electric-Induction-Welded — 1.00
Submerged Arc-Welded — 1.00
Furnace Lap-Welded 0.80 0.80 (3)
Furnace Butt-Welded 0.60 0.60
API 5LS Electric-Resistance-Welded — 1.00
Submerged Arc-Welded — 1.00
API 5LX Seamless 1.00 1.00
Electric-Resistance-Welded 1.00 1.00
Electric-Flash-Welded 1.00 1.00
Electric-Induction-Welded — 1.00
Submerged Arc-Welded 1.00 1.00
API 5LU Seamless — 1.00
Electric-Resistance-Welded — 1.00
Electric-Flash-Welded — 1.00
Electric-Induction-Welded — 1.00
Submerged Arc-Welded — 1.00
Known Known (4) (5)
Unknown Seamless 1.00 (6) 1.00 (6)
Unknown Electric-Resistance or Flash-Welded 0.85 (6) 1.00 (6)
Unknown Electric-Fusion-Welded 0.80 (6) 0.80 (6)
Unknown Furnace Lap-Welded or over NPS 4 0.80 (7) 0.80 (7)
Unknown Furnace Butt-Welded or NPS 4 and smaller 0.60 (8) 0.60 (8)
NOTES: (1) Definitions for the various pipe types (weld joints) are given in 400.2.
(2) A weld joint factor of 1.0 may be used for electric-resistance-welded or electric-flash-welded pipe manufactured prior to 1959
where (a) pipe furnished under this classification has been subjected to supplemental tests and/or heat treatments as agreed
to by the supplier and the purchaser, and such supplemental tests and/or heat treatment demonstrate the strength charac-
teristics of the weld to be equal to the minimum tensile strength specified for the pipe, or (b) pipe has been tested as required
for a new pipeline in accordance with 437.4.1.
(3) Manufacture was discontinued and process deleted from API 5L in 1962.
(4) Factors shown above for pipe manufactured before 1959 apply for new or used (reclaimed) pipe if pipe specification and
pipe type are known and it is known that pipe was manufactured before 1959 or not known whether manufactured after
1958.
(5) Factors shown above for pipe manufactured after 1958 apply for new or used (reclaimed) pipe if pipe specification and pipe
type are known and it is known that pipe was manufactured after 1958.
(6) Factor applies for new or used pipe of unknown specification and ASTM A120 if type of weld joint is known.
(7) Factor applies for new or used pipe of unknown specification and ASTM A120 if type of weld joint is known to be furnace
lap-welded, or for pipe over NPS 4 if type of joint is unknown.
(8) Factor applies for new or used pipe of unknown specification and ASTM A120 if type of weld joint is known to be furnace
butt-welded, or for pipe NPS 4 and smaller if type of joint is unknown.

Reproduced from ANSI/ASME Code B31-4-1979, Table 402.4.3. Reprinted courtesy of The American Society of Mechanical Engineers.