Standard and Grades: API 5L X56 (Q, M, QS, MS), ISO 3183 L390
Product Specification Level: PSL1, PSL2, Sour Service, Offshore Services
Manufacturing types: Seamless and welded
Outer Diameters: Seamless up to 40”, welded up to 100”
Thickness Schedule: up to SCH 160
Coating Types: Black Painting, Varnished, FBE, 3PE/3LPE, 3PP, Galvanized, Concrete Weight Coating.
API 5L X56 pipe is a medium grade pipe material in API 5L standard specifications. It’s yield strength minimum in 390 Mpa (56,600 psi), minimum tensile strength 490 Mpa.
API 5L X56 also called L390 Pipe named by yield strength 390 Mpa, it covers manufacturing types in seamless and welded (ERW, EFW, SAW) types. L390 pipe contains two product specification levels PSL1, PSL2. And for different services like sour, onshore, offshore services.
API 5L X56 Pipe Types
Ranges by Product Specification Level: PSL1, PSL2, Sour Services
API 5L X56 PSL1, for the pipes in common delivery condition of As Rolled.
API 5L X56N/M/Q, for PSL2 pipe with delivery condition of N, M, and Q.
API 5L X56NS/MS/QS, for PSL2 pipes with sour services.
API 5L X56NO/MO/QO, for offshore services.
Suffix Letter Means
R: As rolled
N: Normalizing rolled, Normalized formed, Normalized
Q: Tempered and quenched
M: Thermomechanical rolled or thermomechanical formed
S: Sour Service
O: Offshore
Manufacturing Types
Seamless: Covers hot rolled seamless and cold drawn seamless.
ERW: Electric Resistance Welded
LSAW: Longitudinal Sub-merged Arc Welding
SSAW: Spiral Sub-merged Arc Welding
HSAW / DSAW: Same with SSAW for spiral welded pipe
Features
API 5L X56 steel pipe has a minimum yield strength of 56,600 psi or 390 Mpa. The current X56 steel pipe are all controlled micro-alloyed carbon-manganese steels. The micro-alloys elements are mainly Nb, V and Ti, and the total content of micro-alloys does not exceed 0.15%. Therefore, the structure of the pipe is composed of acicular ferrite and bainite, and it generally has good welding performances.
Advantages:
a. High strength than Grade B and X42, X46, X52
b. High resistance to dynamic tearing
c. High low temperature impact toughness
d. Low ductile-brittle transition temperature
e. Acid service suitability, applicable to NACE
f. Economy and long lasting
Its excellent performance is due to the ultra-low carbon acicular ferrite structure, high density dislocations interact with fine precipitation phases.
| 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 | |
| PSL 2 | 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 |
| 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 |
| 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: | ||||
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