API 5L Line Pipe
API 5L Pipe Standard Scope
ANSI / API 5L specifies the manufacture of two product levels (PSL1 and PSL2) of seamless and welded steel pipe for the use of a pipeline in the transportation of petroleum and natural gas. For material use in a sour service application, refer to Annex H; for offshore service application, refer to Annex J of API 5L 45th Edition.
In a word, API 5L pipe is the carbon steel pipe applied to the oil and gas transmission system. Meanwhile other fluids like steam, water, slurry also could adopt the API 5L standard for the transmission purposes.
Different Manufacturing Types
API 5L specification covers the manufacturing types in welded and seamless.
Welded Type: ERW, SAW, DSAW, LSAW, SSAW, HSAW Pipe
For API 5L welded pipe common types as Follows:
ERW: Electric Resistance Welded, for pipe diameter normally under 24 inch.
DSAW/SAW: Double Submerged Arc Welding / Submerged Arc Welding, a substitute welding method than ERW for larger diameter pipes.
LSAW: Longitudinal SAW, for diameter up to 48 inch. Also called JCOE manufacturing process.
SSAW/HSAW: Spiral Subemerged Arc Welded / Helical SAW, pipe diameters up to 100 inch.
Seamless Type: Hot Rolled Seamess and Cold Rolled Seamless Pipe
Seamless manufacturing type usually for the small diameters pipe, normally diameter under 24 inch.
(For the pipe diameter is less than 150 mm or 6 inch, the seamless steel pipe is more applied than steel pipe in welded.)
There are also big diameters seamless pipe. By hot rolled manufacturing process we could get seamless pipe diameters at most 20 inch (508 mm). But if you need the seamless pipe more than 20”, we can get it through hot expanding processes, maximum diameters to 40 inch 1016 mm.
Delivery Condition
PSL | Delivery Condition | Pipe grade |
PSL1 | As-rolled, normalized, normalizing formed | A |
As-rolled, normalizing rolled, thermomechanical rolled, thermo-mechanical formed, normalizing formed, normalized, normalized and tempered or if agreed Q&T SMLS only | B | |
As-rolled, normalizing rolled, thermomechanical rolled, thermo-mechanical formed, normalizing formed, normalized, normalized and tempered | X42, X46, X52, X56, X60, X65, X70 | |
PSL2 | As-rolled | BR, X42R |
Normalizing rolled, normalizing formed, normalized or normalized and tempered | BN, X42N, X46N, X52N, X56N, X60N | |
Quenched and tempered | BQ, X42Q, X46Q, X56Q, X60Q, X65Q, X70Q, X80Q, X90Q, X100Q | |
Thermomechanical rolled or thermomechanical formed | BM, X42M, X46M, X56M, X60M, X65M, X70M, X80M | |
Thermomechanical rolled | X90M, X100M, X120M | |
The suffice (R, N, Q or M) for PSL2 grades, belongs to the steel grade |
Chemical Composition for PSL 1 pipe with t ≤ 0.984”
Steel Grade | Mass fraction, % based on heat and product analyses a,g | ||||||
C | Mn | P | S | V | Nb | Ti | |
max b | max b | max | max | max | max | max | |
Seamless Pipe | |||||||
A | 0.22 | 0.9 | 0.3 | 0.3 | – | – | – |
B | 0.28 | 1.2 | 0.3 | 0.3 | c,d | c,d | d |
X42 | 0.28 | 1.3 | 0.3 | 0.3 | d | d | d |
X46 | 0.28 | 1.4 | 0.3 | 0.3 | d | d | d |
X52 | 0.28 | 1.4 | 0.3 | 0.3 | d | d | d |
X56 | 0.28 | 1.4 | 0.3 | 0.3 | d | d | d |
X60 | 0.28 e | 1.40 e | 0.3 | 0.3 | f | f | f |
X65 | 0.28 e | 1.40 e | 0.3 | 0.3 | f | f | f |
X70 | 0.28 e | 1.40 e | 0.3 | 0.3 | f | f | f |
Welded Pipe | |||||||
A | 0.22 | 0.9 | 0.3 | 0.3 | – | – | – |
B | 0.26 | 1.2 | 0.3 | 0.3 | c,d | c,d | d |
X42 | 0.26 | 1.3 | 0.3 | 0.3 | d | d | d |
X46 | 0.26 | 1.4 | 0.3 | 0.3 | d | d | d |
X52 | 0.26 | 1.4 | 0.3 | 0.3 | d | d | d |
X56 | 0.26 | 1.4 | 0.3 | 0.3 | d | d | d |
X60 | 0.26 e | 1.40 e | 0.3 | 0.3 | f | f | f |
X65 | 0.26 e | 1.45 e | 0.3 | 0.3 | f | f | f |
X70 | 0.26e | 1.65 e | 0.3 | 0.3 | f | f | f |
a. Cu ≤ = 0.50% Ni; ≤ 0.50%; Cr ≤ 0.50%; and Mo ≤ 0.15%, b. For each reduction of 0.01% below the specified maximum concentration for carbon, an increase of 0.05% above the specified maximum concentration for Mn is permissible, up to a maximum of 1.65% for grades ≥ L245 or B, but ≤ L360 or X52; up to a maximum of 1.75% for grades > L360 or X52, but < L485 or X70; and up to a maximum of 2.00% for grade L485 or X70., c. Unless otherwise agreed NB + V ≤ 0.06%, d. Nb + V + TI ≤ 0.15%, e. Unless otherwise agreed., f. Unless otherwise agreed, NB + V = Ti ≤ 0.15%, g. No deliberate addition of B is permitted and the residual B ≤ 0.001% |
Chemical Composition for PSL 2 pipe with t ≤ 0.984”
Steel Grade | Mass fraction, % based on heat and product analyses | Carbon Equiv a | ||||||||||||||||||
C | Si | Mn | P | S | V | Nb | Ti | Other | CE IIW | CE Pcm | ||||||||||
max b | max | max b | max | max | max | max | max | max | max | |||||||||||
Seamless and Welded Pipe | ||||||||||||||||||||
BR | 0.24 | 0.4 | 1.2 | 0.025 | 0.015 | c | c | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X42R | 0.24 | 0.4 | 1.2 | 0.025 | 0.015 | 0.06 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
BN | 0.24 | 0.4 | 1.2 | 0.025 | 0.015 | c | c | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X42N | 0.24 | 0.4 | 1.2 | 0.025 | 0.015 | 0.06 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X46N | 0.24 | 0.4 | 1.4 | 0.025 | 0.015 | 0.07 | 0.05 | 0.04 | d,e,l | 0.43 | 0.25 | |||||||||
X52N | 0.24 | 0.45 | 1.4 | 0.025 | 0.015 | 0.1 | 0.05 | 0.04 | d,e,l | 0.43 | 0.25 | |||||||||
X56N | 0.24 | 0.45 | 1.4 | 0.025 | 0.015 | 0.10f | 0.05 | 0.04 | d,e,l | 0.43 | 0.25 | |||||||||
X60N | 0.24f | 0.45f | 1.40f | 0.025 | 0.015 | 0.10f | 0.05f | 0.04f | g,h,l | As agreed | ||||||||||
BQ | 0.18 | 0.45 | 1.4 | 0.025 | 0.015 | 0.05 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X42Q | 0.18 | 0.45 | 1.4 | 0.025 | 0.015 | 0.05 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X46Q | 0.18 | 0.45 | 1.4 | 0.025 | 0.015 | 0.05 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X52Q | 0.18 | 0.45 | 1.5 | 0.025 | 0.015 | 0.05 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X56Q | 0.18 | 0.45f | 1.5 | 0.025 | 0.015 | 0.07 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X60Q | 0.18f | 0.45f | 1.70f | 0.025 | 0.015 | g | g | g | h,l | 0.43 | 0.25 | |||||||||
X65Q | 0.18f | 0.45f | 1.70f | 0.025 | 0.015 | g | g | g | h,l | 0.43 | 0.25 | |||||||||
X70Q | 0.18f | 0.45f | 1.80f | 0.025 | 0.015 | g | g | g | h,l | 0.43 | 0.25 | |||||||||
X80Q | 0.18f | 0.45f | 1.90f | 0.025 | 0.015 | g | g | g | i,j | As agreed | ||||||||||
X90Q | 0.16f | 0.45f | 1.9 | 0.02 | 0.01 | g | g | g | j,k | As agreed | ||||||||||
X100Q | 0.16f | 0.45f | 1.9 | 0.02 | 0.01 | g | g | g | j,k | As agreed | ||||||||||
Welded Pipe | ||||||||||||||||||||
BM | 0.22 | 0.45 | 1.2 | 0.025 | 0.015 | 0.05 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X42M | 0.22 | 0.45 | 1.3 | 0.025 | 0.015 | 0.05 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X46M | 0.22 | 0.45 | 1.3 | 0.025 | 0.015 | 0.05 | 0.05 | 0.04 | e,l | 0.43 | 0.25 | |||||||||
X52M | 0.22 | 0.45 | 1.4 | 0.025 | 0.015 | d | d | d | e,l | 0.43 | 0.25 | |||||||||
X56M | 0.22 | 0.45f | 1.4 | 0.025 | 0.015 | d | d | d | e,l | 0.43 | 0.25 | |||||||||
X60M | 0.12f | 0.45f | 1.60f | 0.025 | 0.015 | g | g | g | h,l | 0.43 | 0.25 | |||||||||
X65M | 0.12f | 0.45f | 1.60f | 0.025 | 0.015 | g | g | g | h,l | 0.43 | 0.25 | |||||||||
X70M | 0.12f | 0.45f | 1.70f | 0.025 | 0.015 | g | g | g | h,l | 0.43 | 0.25 | |||||||||
X80M | 0.12f | 0.45f | 1.85f | 0.025 | 0.015 | g | g | g | i,j | .043f | 0.25 | |||||||||
X90M | 0.1 | 0.55f | 2.10f | 0.02 | 0.01 | g | g | g | i,j | – | 0.25 | |||||||||
X100M | 0.1 | 0.55f | 2.10f | 0.02 | 0.01 | g | g | g | i,j | – | 0.25 | |||||||||
a. SMLS t>0.787”, CE limits shall be as agreed. The CEIIW limits applied fi C > 0.12% and the CEPcm limits apply if C ≤ 0.12%, |
Mechanical properties
Pipe Grade | Tensile Properties – Pipe Body of SMLS and Welded Pipes PSL 1 | Seam of Welded Pipe | ||
Yield Strength a | Tensile Strength a | Elongation | Tensile Strength b | |
Rt0,5 PSI Min | Rm PSI Min | (in 2in Af % min) | Rm PSI Min | |
A | 30,500 | 48,600 | c | 48,600 |
B | 35,500 | 60,200 | c | 60,200 |
X42 | 42,100 | 60,200 | c | 60,200 |
X46 | 46,400 | 63,100 | c | 63,100 |
X52 | 52,200 | 66,700 | c | 66,700 |
X56 | 56,600 | 71,100 | c | 71,100 |
X60 | 60,200 | 75,400 | c | 75,400 |
X65 | 65,300 | 77,500 | c | 77,500 |
X70 | 70,300 | 82,700 | c | 82,700 |
a. For intermediate grade, the difference between the specified minimum tensile strength and the specified minimum yield for the pipe body shall be as given for the next higher grade. | ||||
b. For the intermediate grades, the specified minimum tensile strength for the weld seam shall be the same as determined for the body using foot note a. | ||||
c. The specified minimum elongation, Af, expressed in percent and rounded to the nearest percent, shall be determined using the following equation: | ||||
Where C is 1 940 for calculation using Si units and 625 000 for calculation using USC units | ||||
Axc is the applicable tensile test piece cross-sectional area, expressed in square millimeters (square inches) , as follows | ||||
– For circular cross-section test pieces, 130mm2 (0.20 in2) for 12.7 mm (0.500 in) and 8.9 mm (.350 in) diameter test pieces; and 65 mm2 (0.10 in2) for 6.4 mm (0.250in) diameter test pieces. | ||||
– For full-section test pieces, the lesser of a) 485 mm2 (0.75 in2) and b) the cross-sectional area of the test piece, derived using the specified outside diameter and the specified wall thickness of the pipe, rounded to the nearest 10 mm2 (0.10in2) | ||||
– For strip test pieces, the lesser of a) 485 mm2 (0.75 in2) and b) the cross-sectional area of the test piece, derived using the specified width of the test piece and the specified wall thickness of the pipe, rounded to the nearest 10 mm2 (0.10in2) | ||||
U is the specified minimum tensile strength, expressed in megapascals (pounds per square inch) |
Tolerances: Outside diameter, out of roundness and wall thickness
Specified Outside Diameter D (in) | Diameter Tolerance, inches d | Out-of-Roundness Tolerance in | ||||
Pipe except the end a | Pipe end a,b,c | Pipe except the End a | Pipe End a,b,c | |||
SMLS Pipe | Welded Pipe | SMLS Pipe | Welded Pipe | |||
< 2.375 | -0.031 to + 0.016 | – 0.031 to + 0.016 | 0.048 | 0.036 | ||
≥2.375 to 6.625 | 0.020D for | 0.015D for | ||||
+/- 0.0075D | – 0.016 to + 0.063 | |||||
By agreement for | By agreement for | |||||
>6.625 to 24.000 | +/- 0.0075D | +/- 0.0075D, but max of 0.125 | +/- 0.005D, but max of 0.063 | 0.020D | 0.015D | |
>24 to 56 | +/- 0.01D | +/- 0.005D but max of 0.160 | +/- 0.079 | +/- 0.063 | 0.015D for but max of 0.060 | 0.01D for but max of 0.500 |
For | For | |||||
By agreement | By agreement | |||||
for | for | |||||
>56 | As agreed | |||||
a. The pipe end includes a length of 4 in ate each of the pipe extremities | ||||||
b. For SMLS pipe the tolerance apply for t≤0.984in and the tolerances for the thicker pipe shall be as agreed | ||||||
c. For expanded pipe with D≥8.625in and for non-expanded pipe, the diameter tolerance and the out-of-roundness tolerance may be determined using the calculated inside diameter or measured inside diameter rather than the specified OD. | ||||||
d. For determining compliance to diameter tolerance, the pipe diameter is defined as the circumference of the pipe in any circumferential plane divide by Pi. |
Wall thickness | Tolerances a |
t inches | inches |
SMLS pipe b | |
≤ 0.157 | -1.2 |
> 0.157 to < 0.948 | + 0.150t / – 0.125t |
≥ 0.984 | + 0.146 or + 0.1t, whichever is the greater |
– 0.120 or – 0.1t, whichever is the greater | |
Welded pipe c,d | |
≤ 0.197 | +/- 0.020 |
> 0.197 to < 0.591 | +/- 0.1t |
≥ 0.591 | +/- 0.060 |
a. If the purchase order specifies a minus tolerance for wall thickness smaller than the applicable value given in this table, the plus tolerance for wall thickness shall be increased by an amount sufficient to maintain the applicable tolerance range. | |
b. For pipe with D≥ 14.000 in and t≥0.984in, the wall thickness tolerance locally may exceed the plus tolerance for wall thickness by an additional 0.05t provided that the plus tolerance for mass is not exceeded. | |
c. The plus tolerance for wall thickens does not apply to the weld area | |
d. See the full API5L spec for full details |