📄 PSL1 L415/X60 Pipeline Steel Plate (GB/T 21237-2018) – Technical Data Sheet
This standard specifies technical requirements for wide and heavy plates of 6mm~50mm thickness for petroleum and natural gas pipelines. L415/X60 (PSL1) is a high-strength pipeline steel offering excellent performance for demanding oil and gas transmission applications requiring superior strength and good weldability.
PSL1 L415/X60 pipeline steel plate conforms to GB/T 21237-2018, fully equivalent to API 5L Grade X60. It is designed for high-pressure oil and gas transmission lines, long-distance pipelines, and structural applications requiring higher strength. With controlled carbon content and optimized microalloying elements (Nb, V, Ti), X60 provides reliable strength (415MPa minimum yield) while maintaining good weldability and toughness, making it an excellent choice for demanding pipeline projects with elevated pressure requirements.
📌 Designation Rules (3.2.1 / 3.2.2)
🔹 Standard Naming (3.2.1)
Example: L415M
L — First letter of "Line" for pipeline
415 — Specified minimum yield strength (MPa)
M — Thermomechanical rolled condition
L415/X60: L415 = yield ≥415MPa, X60 = API 5L X60 grade (PSL1, hot-rolled/normalized/normalized-rolled)
🔸 API 5L Common Naming (3.2.2)
Example: X60
X — Line pipe identifier
60 — Minimum yield strength (ksi) = 60 × 6.895 ≈ 414 MPa (rounded to 415 MPa)
L415/X60 corresponds to API 5L Grade X60, yield ≥415MPa.
📘 Per Table 1, PSL1 hot-rolled/normalized state = L415/X60.
🧪 Chemical Composition (PSL1, ladle & product analysis)
| Grade | Cb (≤%) | Mnb (≤%) | P (≤%) | S (≤%) | V | Nb | Ti | Other restrictions |
|---|---|---|---|---|---|---|---|---|
| L415/X60 | 0.26* | 1.40* | 0.030 | 0.030 | —f | —f | —f | Cu≤0.50, Ni≤0.50, Cr≤0.50, Mo≤0.15 |
📋 Table 2 Notes:
a Copper max 0.50%; Nickel max 0.50%; Chromium max 0.50%; Molybdenum max 0.15%.
b For each 0.01% reduction in carbon below 0.26%, manganese may be increased by 0.05% above 1.40%, but max Mn ≤1.75% for L415/X60.
f Unless otherwise agreed, total Nb+V+Ti ≤0.15%.
g Unless otherwise specified, boron not intentionally added, residual B ≤0.001%.
* For L415/X60 and higher grades, the maximum carbon and manganese limits may be adjusted by agreement.
⚙️ Mechanical & Technological Properties (PSL1 Table 4)
| Steel grade | Rt0.5 (MPa) ≥ | Rm (MPa) ≥ | A50mmc (%) ≥ | 180° bend test | Specimen direction |
|---|---|---|---|---|---|
| L415/X60 | 415 | 520 | 17 | D=2a, no cracks | Transverse |
📋 Table 4 Notes:
a Tensile property range to be agreed between purchaser and supplier to ensure finished pipe compliance.
b Specimen direction transverse, to be stated in contract.
c Standard gauge length 50mm. Arbitration specimen: 50mm gauge length, 38mm width.
📐 Min elongation formula: A50mm=1940×S00.2/Rm0.9. Bend former diameter D=2a.
🔄 L415/X60 vs API 5L X60 – What's the Difference?
🇨🇳 GB/T 21237 L415/X60
- Standard: Chinese national standard GB/T 21237-2018 (PSL1)
- Yield strength: ≥415 MPa (60.2 ksi)
- Tensile strength: ≥520 MPa
- Carbon (max): 0.26% (adjustable)
- Manganese (max): 1.40% (adjustable up to 1.75%)
- Delivery condition: Hot-rolled, normalized, normalized-rolled
- Typical use: High-pressure oil & gas pipelines, long-distance transmission, offshore pipelines
🇺🇸 API 5L Grade X60
- Standard: API Spec 5L (PSL1 / PSL2)
- Yield strength: ≥414 MPa (60,000 psi)
- Tensile strength: ≥520 MPa (75,400 psi)
- Carbon (max): 0.26% (X60)
- Manganese (max): 1.40%
- Delivery condition: As-rolled, normalized, TMCP, Q&T
- Typical use: High-pressure oil/gas pipelines, sour service, arctic applications
💡 Bottom line: L415/X60 (GB/T 21237) is fully equivalent to API 5L Grade X60 in mechanical properties and chemical composition. The naming differs — "L" stands for "Line" in the Chinese standard, while API uses "X" — but material performance is identical. X60 is a high-strength pipeline grade widely used for long-distance high-pressure transmission. For projects requiring API 5L X60 steel plates, L415/X60 from Chinese mills is a direct, cost-effective substitute trusted by engineers for demanding high-pressure pipeline applications worldwide.
📜 Supplementary Chemical Requirements (6.1.3 ~ 6.1.6)
✅ 6.1.3 Thickness > 25.0mm — Chemical composition may be agreed between supplier and purchaser for heavy plates up to 50mm.
✅ 6.1.4 Ladle analysis & CE — Supplier provides ladle analysis and carbon equivalent (CE); product analysis upon negotiation.
✅ 6.1.5 Intermediate grades — Intermediate grades between consecutive Table 2 grades may be supplied by agreement.
✅ 6.1.6 Other alloying elements — For L290/X42 and higher, other elements (Nb, V, Ti) may be added by agreement.
🏭 Smelting Method · Delivery Condition (6.3 & 6.4)
🔥 6.3 Smelting process
Oxygen converter or electric furnace. For PSL1 L415/X60 conventional smelting with controlled residuals.
📦 6.4 Delivery condition
Hot-rolled (R), normalized (N), normalized-rolled. L415/X60 typically delivered as hot-rolled or normalized. TMCP available by agreement.
📏 Dimensions & Other Technical Specifications
Dimensions (Clause 5): Per GB/T 709. Thickness 6mm~50mm. Trimmed/untrimmed edges. Tolerances per GB/T 709.
Grain size (6.6): Not mandatory for PSL1, reference No.7 or finer.
Non-metallic inclusions (6.7): PSL1 no mandatory limits, but clean steel practice required.
Banding (6.8): Not specified for PSL1; for reference only.
📋 Summary: Steel plate surfaces must be free from cracks, blisters, folds, inclusions, and visually detectable laminations. Defect removal permitted within tolerance limits, welding repair prohibited.
✅ 6.9.1 The steel plate surface shall be free from cracks, blisters, folds, bubbles, inclusions, and visually detectable laminations harmful to use. Removal allowed up to half thickness tolerance, maintaining min thickness.
✅ 6.9.2 Other local imperfections that do not affect use are permitted, provided minimum thickness is maintained.
✅ 6.9.3 For untrimmed edges, edge crack depth shall not exceed half width tolerance, min width maintained.
✅ 6.9.4 Upon agreement, defect depth and area may be measured per GB/T 14977.
✅ 6.9.5 Welding repair on steel plate surface is not permitted.
📋 Ordering content & Inspection rules
📑 Ordering content (Clause 4)
- Standard: GB/T 21237—2018
- Quality level: PSL1
- Grade: L415/X60
- Dimensions & thickness precision
- Delivery condition & edge condition
- Specimen direction (transverse)
- Application: gas/oil/fluid
🔬 Inspection rules
Batch: same grade, heat, thickness, rolling schedule. ≤60 tons per batch. Test methods: GB/T 228.1 (tensile), GB/T 232 (bend), GB/T 4336 (chemistry). Rounding per GB/T 8170.