Chinese grade pipeline steel PSL1 L210/A chemical composition a,g Mechanical and technological properties of steel plates
PSL1 L210/A Approaching Grade Lookup Table
3.2 Designation Method
3.2.1 The steel grade consists of three parts: the first letter of "Line" representing the pipeline, the specified minimum yield strength of the steel pipe, and the delivery condition (applicable only to PSL2 quality grade). Example: L210/A.
L ——— Represents the first letter of "Line" for the pipeline;
210 ——— Represents the minimum yield strength specified for the steel pipe, in megapascals (MPa);
A ——— The "A" usually indicates that the steel meets specific standards or quality inspection requirements, such as certification according to standards like API (American Petroleum Institute), ensuring that the steel has certain properties such as pressure resistance and corrosion resistance.
PSL1 Chemical Composition
| Grade | Cᵇ | Mnᵇ | P | S | V | Nb | Ti | Steel grade | Total elongation strength a,b Rt0.5/MPa | Tensile strength a,b Rm/MPa | Elongation after fracture c/% A | 180°Bending test (a-Sample thickness D-Bending indenter diameter) |
| L210/A | ≤0.22 | ≤0.90 | ≤0.030 | ≤0.030 | - | - | - | L210/A | ≥210 | ≥335 | ≥25 | D=2a |
| a.The maximum content of copper is 0.50%, the maximum content of nickel is 0.50%, the maximum content of chromium is 0.50%, and the maximum content of molybdenum is 0.15%. b.For every 0.01% decrease in carbon content compared to the maximum specified carbon content, the manganese content may be 0.05% higher than the maximum specified manganese content. However, for L245/B, L290/X42, L320/X46, and L360/X52, the maximum manganese content should not exceed 1.65%, for L390/X56, L415/X60, and L450/X65, the maximum manganese content should not exceed 1.75%, and for L485/X70, the manganese content should not exceed 2.00%. c.Unless otherwise agreed, the total content of niobium and vanadium shall not exceed 0.06%. d.The total content of niobium, vanadium, and titanium should not exceed 0.15%. e.Unless otherwise agreed. f.Unless otherwise agreed, the total content of niobium, vanadium, and titanium shall not exceed 0.15%. g.Unless otherwise specified, boron should not be intentionally added, and the residual boron content should not exceed 0.001%. |
a.When selecting grades from the table, the buyer and supplier shall negotiate and determine a suitable range of tensile properties to ensure that the tensile properties of the finished steel pipes meet the requirements of the corresponding standards. b.The tensile test specimen orientation listed in the table shall be determined by the purchaser and shall be specified in the contract. Generally, the tensile test specimen orientation is the transverse direction of the corresponding steel pipe. c.According to the standard gauge length test, a proportional gauge length test can also be used when the user has special requirements. In case of disputes, arbitration will be conducted using a specimen with a gauge length of 50 mm and a width of 38 mm. The minimum elongation after fracture when the gauge length is 50 mm is calculated using this formula:A50mm=1940*S00.2/Rm0.9 S0: Original cross-sectional area of the tensile specimen, in square millimeters. Rm: Specified minimum tensile strength, in megapascals. Note 1: For round bar specimens, S0 is 130 mm² for specimens with diameters of 12.7 mm and 8.9 mm, S0 is 65 mm² for specimens with a diameter of 6.4 mm. Note 2: For full-thickness rectangular specimens, take the smaller of a) 485 mm² and b) specimen cross-sectional area (nominal thickness * specimen width), rounded to the nearest 10 mm². |
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6.3 Smelting Method
Steel shall be smelted in an oxygen converter or electric furnace. PSL2 grade steel shall be refined outside the ladle; L485/X70 and higher strength grades shall be degassed under vacuum. Unless otherwise specified by the purchaser, the smelting method shall be selected by the supplier.
6.4 Delivery Condition
Steel plates shall be delivered in hot-rolled, normalized, normalized rolled, thermomechanically rolled, or quenched and tempered conditions.
6.5 Mechanical and Technological Properties
6.5.1 For intermediate grades between two consecutive grades with a specified total elongation strength higher than L290/X42, their mechanical and technological properties shall be determined through negotiation between the supplier and the purchaser.
6.5.2 The mechanical and technological properties of PSL1 steel plates shall conform to the provisions of the table above.
6.9 Surface Quality
6.9.1 The surface of the steel plate shall be free from defects harmful to use, such as cracks, scabs, folds, bubbles, inclusions, and visible delamination. If such defects are present, they may be removed, but the depth of removal shall not exceed half the thickness tolerance of the steel plate, while ensuring the minimum allowable thickness of the steel plate. The removed area shall be smooth and without sharp edges.
6.9.2 Other local defects that do not affect use are allowed on the surface of the steel plate, but the minimum allowable thickness of the steel plate shall be ensured.
6.9.3 For steel plates delivered without trimmed edges, the depth of edge cracks and other defects in the width direction shall not exceed half the allowable width deviation, and the minimum width of the steel plate shall be ensured.
6.9.4 With the agreement of both the supplier and the purchaser, the defect depth and affected area may also be determined according to GB/T 14977.
6.9.5 Welding repairs are not permitted on the surface of the steel plate.