Comprehensive analysis of API 5L X42N seamless steel tube

1. Definition and Standards

API 5L X42N seamless steel tube is a high-performance seamless steel pipe for pipelines that meets the API SPEC 5L standard. It belongs to PSL2 (specification level 2) and is suitable for oil and gas transportation scenarios with stricter requirements for chemical composition, mechanical properties, and corrosion resistance. In its naming convention, "X42" represents a minimum yield strength of 42000 psi (approximately 290 MPa), and "N" represents specific quality requirements under PSL2 (such as sulfur resistance or low-temperature toughness).

2. Material and Chemical Composition

Domestic corresponding grade: X42N corresponds to L245N or L290N in Chinese standards, belonging to low-alloy high-strength steel.

Chemical composition: Mainly composed of low carbon (C ≤ 0.22%), low sulfur (S ≤ 0.015%), and low phosphorus (P ≤ 0.025%), with trace alloying elements (such as Mn, Nb, V) added to enhance strength and toughness.

3. Specification parameters

Outer diameter range: 21.3mm~1067mm (1/2 "~42"), covering the requirements of small-diameter instrument pipes to large-diameter main pipelines.

Wall thickness range: 2mm~150mm, supporting high-pressure (such as 30MPa or above) conveying scenarios.

Delivery status: Usually in hot-rolled or normalized state, some special purposes require quenching and tempering treatment.

4. Application scenarios

Oil and gas long-distance pipelines: used for onshore and subsea high-pressure oil and gas transmission trunk lines, especially suitable for sulfur-containing (H ₂ S) or low-temperature (below -20 ℃) environments.

Refining facilities: gathering and transportation pipelines and process pipelines for transporting acidic media such as sulfur-containing crude oil and wet natural gas.

5. Performance characteristics

High pressure resistance: yield strength ≥ 290MPa, tensile strength ≥ 415MPa, able to withstand high-pressure transportation demand of 38.

Corrosion resistance: Through sulfur phosphorus control and calcification treatment, it has the ability to resist hydrogen sulfide stress corrosion (SSC) and hydrogen induced cracking (HIC).

Low temperature toughness: maintains good impact toughness below -20 ℃, suitable for cold regions or deep-sea environments.

6. Suppliers and Certification

Provide X42N seamless steel pipes that meet the dual certification of API 5L and GB/T 9711.

Testing requirements: Third party HIC, SSC, and low-temperature impact test reports must be provided to ensure compliance with PSL2 standards.

summarize

API 5L X42N seamless steel pipe has become the preferred material for high-pressure, sulfur-containing, or low-temperature scenarios in the oil and gas industry due to its high strength, corrosion resistance, and low-temperature adaptability. When selecting, special attention should be paid to the supplier's PSL2 certification and performance testing reports in specific environments.