API 5L SEAMLESS & WELDED PIPE

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.

Process

Ingots, blooms, billets, coils or plates used for the manufacture of pipe shall be made via basic oxygen, electric furnace or open hearth in combination with a ladle refining process. For PSL2, the steel shall be killed and melted according to a fine grain practice. Coil or plate used for PSL2 pipe shall not contain any repair welds.

Delivery condition

Chemical requirements

Chemical Composition for PSL 1 pipe with t ≤ 0.984”

Chemical Composition for PSL 2 pipe with t ≤ 0.984”

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)

Pipe Grade	Tensile Properties – Pipe Body of SMLS and Welded Pipes PSL 2						Seam of Welded Pipe
	Yield Strength a		Tensile Strength a		Ratio a,c	Elongation	Tensile Strength d
	Rt0,5  PSI Min		Rm  PSI Min		R10,5IRm	(in 2in)	Rm (psi)
						Af %
	Minimum	Maximum	Minimum	Maximum	Maximum	Minimum	Minimum
BR, BN,BQ,BM	35,500	65,300	60,200	95,000	0.93	f	60,200
X42,X42R,X2Q,X42M	42,100	71,800	60,200	95,000	0.93	f	60,200
X46N,X46Q,X46M	46,400	76,100	63,100	95,000	0.93	f	63,100
X52N,X52Q,X52M	52,200	76,900	66,700	110,200	0.93	f	66,700
X56N,X56Q,X56M	56,600	79,000	71,100	110,200	0.93	f	71,100
X60N,X60Q,S60M	60,200	81,900	75,400	110,200	0.93	f	75,400
X65Q,X65M	65,300	87,000	77,600	110,200	0.93	f	76,600
X70Q,X65M	70,300	92,100	82,700	110,200	0.93	f	82,700
X80Q,X80M	80,.500	102,300	90,600	119,700	0.93	f	90,600
a. For intermediate grade, refer to the full API5L specification.
b. for grades > X90 refer to the full API5L specification.
c. This limit applies for pies with D> 12.750 in
d. For intermediate grades, the specified minimum tensile strength for the weld seam shall be the same value as was determined for the pipe body using foot a.
e. for pipe requiring longitudinal testing, the maximum yield strength shall be ≤ 71,800 psi
f. 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
g. Lower values fo R10,5IRm may be specified by agreement
h. for grades > x90 refer to the full API5L specification.

Hydrostatic test

Pipe to withstand a hydrostatic test without leakage through the weld seam or the pipe body. Jointers need not be hydrostatic tested provide the pipe sections used were successfully tested.

Bend test

No cracks shall occur in any portion of the test piece and no opening of the weld shall occur.

Flattening test

Acceptance criteria for flattening test shall be:

• EW pipes D<12.750 in:
• X60 with T 500in. There shall be no opening of the weld before the distance between
• the plates is less than 66% of the original outside diameter. For all grades and wall, 50%.
• For pipe with a D/t > 10, there shall be no opening of the weld before the distance between
• the plates is less than 30% of the original outside diameter.
• For other sizes refer to the full API 5L specification.

CVN impact test for PSL2

Many PSL2 pipe sizes and grades require CVN. Seamless pipe is to be tested in the body.
Welded pipe is to be tested in the body, pipe weld and heat-affected zone.
Refer to the full API 5L specification for the chart of sizes and grades and required absorbed energy values.

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.