API 5L X65M X70M PSL2 LSAW STEEL PIPE Longitudinal Submerged Welded Steel

Outer Diameter (OD): 406.4mm ~ 1422.4mm (16inch ~ 56inch), support custom large-diameter customization

Wall Thickness (WT): 6.0mm ~ 40.0mm, meet high-pressure thick-wall pipeline engineering requirements

Standard Length: Single Random Length (SRL): 5.8~7.3m; Double Random Length (DRL): 11.0~13.0m; fixed fixed-length customization supported

Pipe End Treatment: Standard bevel end (30°±5° bevel angle, root face 1.6±0.8mm) per ASME B16.25; plain end optional

Executive Standard: API 5L (44th Edition), ISO 3183

Welding Process: Double-sided multi-pass submerged arc welding, automatic welding forming

NDT Inspection: 100% ultrasonic testing (UT) / radiographic testing (RT) for weld seams, full-body flaw detection

Hydrostatic Test: Full-pipe hydraulic pressure test, no leakage and permanent deformation, test pressure customized per wall thickness

Dimension Tolerance: Strictly controlled within API standard range, ovality ≤0.5%, straightness ≤1.5mm/m

Technical Parameters

1. Chemical Composition (PSL2, Max Weight %)

Strict low-carbon and low-impurity design, reducing carbon equivalent to ensure excellent weldability and anti-brittle performance, fully compliant with API 5L PSL2 specifications.

Grade	C	Si	Mn	P	S	Nb+V+Ti	CE(IIW)	CE(Pcm)
X65M PSL2	0.12	0.45	1.60	0.025	0.015	0.15	0.43	0.25
X70M PSL2	0.12	0.45	1.70	0.025	0.015	0.15	0.43	0.25

Note: No intentional addition of boron; residual B ≤ 0.001%; Cu ≤ 0.50%, Ni ≤ 0.30%, Cr ≤ 0.30%, Mo ≤ 0.15%

 

2. Mechanical Properties (PSL2 Standard)

Grade	Yield Strength (MPa)	Tensile Strength (MPa)	Elongation (Min %)	Charpy Impact Energy (-20℃, J)
X65M PSL2	448 - 565	531 - 758	22	≥27 (Pipe Body) / ≥41 (Weld Seam)
X70M PSL2	483 - 621	565 - 758	21	≥27 (Pipe Body) / ≥41 (Weld Seam)

Note: Custom low-temperature impact test (-40℃) is available for ultra-low temperature project requirements

 

3.Grade Explanation (X65M / X70M)

X Series: API 5L pipeline steel grade, the number represents the minimum yield strength (ksi)

M Code: Thermo-mechanical controlled rolling process, no subsequent heat treatment required, excellent low-temperature toughness and weldability, effectively preventing welding crack and brittle fracture

X65M: Medium-high strength grade, balanced toughness and economy, widely used for conventional oil and gas transmission

X70M: High-strength grade, higher bearing pressure, suitable for long-distance, large-diameter, high-pressure trunk pipelines

PSL2 Upgrade Advantages vs PSL1: Strict chemical composition limits (lower C, P, S), mandatory Charpy V-notch impact test, standardized tensile & hardness test, 100% NDT inspection, higher dimensional tolerance control, applicable for critical pipeline projects with high safety requirements.

 

This product is aLongitudinal Submerged Arc Welded (LSAW)carbon steel line pipe manufactured in full complianceAPI 5L PSL2standard, covering two mainstream grades:X65MandX70M. The letter "M" indicates thermo-mechanical controlled processing (TMCP), which endows the pipe with excellent low-temperature toughness, stable mechanical properties and superior weldability compared with conventional normalized steel pipes. All pipes are finished3LPE (3-layer Polyethylene)external anti-corrosion coating, the most reliable anti-corrosion solution for long-distance oil & gas transmission pipelines.

LSAW pipe adopts single-piece steel plate rolling and double-sided submerged arc welding process, featuring uniform wall thickness, high roundness, small welding residual stress and high structural stability. As a high-standard PSL2 grade pipe, it supports strict non-destructive testing, low sulfur and low carbon composition control, and mandatory impact test, suitable for harsh working conditions such as long-distance transmission, high pressure, low temperature and corrosive environments.

4.Strict Quality Inspection & Testing

All PSL2 grade pipes implement full-item inspection to ensure 100% compliance with API 5L standards:

Chemical Analysis: Spectroscopic detection of all elements, strictly controlling carbon equivalent and impurity content

Mechanical Test: Tensile test, bending test, Charpy low-temperature impact test, hardness test

Hydrostatic Pressure Test: Full-length pressure maintaining test, no leakage, stable pressure value

NDT Inspection: 100% ultrasonic testing for weld seams and pipe body, X-ray inspection for key sections

Coating Test: Spark leakage detection, coating thickness test, adhesion test, impact resistance test

Dimensional Inspection: Full-size sampling inspection to ensure tolerance compliance

3LPE External Anti-Corrosion Coating System

3LPE is the most mainstream and high-performance external anti-corrosion technology for buried steel pipelines, with excellent anti-corrosion, anti-aging and mechanical damage resistance, service life up to 30-50 years.

Three-Layer Structure

First Layer (FBE Fusion Bonded Epoxy): Thickness 80-120μm, tightly bonded with steel pipe surface, excellent chemical resistance and anti-corrosion adhesion

Second Layer (Adhesive): Modified copolymer adhesive, thickness 200-300μm, connecting FBE and PE layer, improving overall coating integrity

Third Layer (PE Polyethylene): High-density polyethylene outer layer, thickness 2.5-3.5mm, strong mechanical protection, anti-impact, anti-abrasion, waterproof and moisture-proof

Application Fields

As high-standard PSL2 LSAW steel pipes with 3LPE anti-corrosion, X65M and X70M grades are widely used in global energy engineering and heavy-duty pipeline projects:

·Oil & Gas Transmission: Long-distance trunk pipelines for crude oil, natural gas, liquefied gas transmission

·Offshore & Coastal Projects: Offshore platform pipelines, coastal buried pipelines (anti-salt corrosion)

·Urban Energy Pipeline Network: High-pressure municipal gas transmission and distribution pipelines

·Industrial Fluid Transportation: High-pressure water injection pipelines, chemical medium transmission pipelines

·Pile Foundation Engineering: Offshore wind power pile pipes, bridge and wharf foundation steel pipes

·Harsh Environment Projects: Low-temperature cold region, high-salinity, high-corrosion area pipeline projects

FAQ

Q1: What is the difference between PSL1 and PSL2 of API 5L standard?

PSL2 is a higher-grade product specification compared with PSL1. It has stricter chemical composition control (lower C, P, S content), mandatory low-temperature impact test, full-scale non-destructive testing, more precise dimensional tolerance, and better low-temperature toughness and safety. PSL2 is mandatory for key long-distance and high-pressure pipeline projects, while PSL1 is only suitable for conventional low-pressure auxiliary pipelines.

Q2: What does the "M" in X65M/X70M mean? What are the advantages?

"M" refers to Thermo-Mechanical Controlled Processing (TMCP). Different from normalizing steel, TMCP rolling optimizes the steel microstructure through controlled rolling and controlled cooling, without subsequent heat treatment. It features lower carbon equivalent, better weldability, excellent low-temperature brittleness resistance, and more stable mechanical properties, effectively avoiding welding cracks and pipeline fracture risks in low-temperature environments.

Q3: Why choose LSAW pipe instead of seamless or spiral welded pipe?

LSAW pipe is formed by single steel plate rolling with double-sided submerged arc welding, with uniform wall thickness, high roundness, flat weld seam and small residual stress. Compared with seamless pipe, it supports larger diameter and thicker wall customization with lower cost; compared with spiral welded pipe, it has shorter weld seam, higher safety factor, no spiral stress concentration, and is more suitable for high-pressure, long-distance key pipeline projects.

Q4: What is the service life of 3LPE anti-corrosion coating?

Under standard buried working conditions, the 3LPE coating has a service life of 30-50 years. It can effectively resist soil corrosion, microbial corrosion and cathodic aging. Strict coating thickness control and factory leakage detection ensure no coating damage, which greatly extends the pipeline service cycle and reduces later maintenance costs.

Q5: Can you provide customized specifications and third-party inspection?

Yes. We support custom outer diameter, wall thickness, fixed length, low-temperature impact parameters and coating thickness. We can provide third-party inspection reports from SGS, BV, TUV and other authoritative institutions, and issue complete factory certificates including chemical composition, mechanical properties, test records and API certification documents.

Q6: What are your delivery terms and lead time?

We support EXW, FOB, CFR, CIF international trade terms. Conventional specifications have sufficient stock with 7-10 days delivery time; customized non-standard specifications take 15-25 days production cycle. We provide professional container packaging, anti-collision protection and complete shipping documents.