In the petrochemical industry, piping systems need to withstand complex working conditions such as high temperature, high pressure and corrosive media for a long time. Therefore, selecting steel pipe materials that comply with international standards is crucial for the safety and long-term stable operation of units. Among numerous industrial piping standards, ASTM A671 is widely used in key piping systems of petrochemical processing units due to its excellent weldability, stable mechanical strength and rigorous quality inspection system. This article will…

In liquefied natural gas (LNG), low-temperature storage and transportation, chemical plants, and energy pipeline systems in cold regions, materials must maintain excellent strength and toughness in low-temperature environments. If steel pipe materials suffer brittle fracture at low temperatures, it will pose severe safety risks to the entire pressure system. Therefore, in many industrial projects, engineers select welded steel pipes complying with the ASTM A671 standard as key pipeline materials. This article will conduct an in-depth analysis of why ASTM A671…

In thermal power plants, combined cycle power plants and large-scale energy projects, piping systems need to withstand high temperature, high pressure and complex operating conditions for a long time. Therefore, selecting welded steel pipes that comply with international standards is crucial to ensuring system safety. Among numerous pressure pipe materials, ASTM A671 standard steel pipes are widely used in power plant steam pipelines, water supply systems and circulating water systems due to their stable performance and reliable welding quality. This…

In petrochemical, electric power, natural gas transmission and refinery projects, engineers often need to select welded steel pipes suitable for pressure piping systems. Among them, ASTM A671 standard steel pipes are widely used in pressure pipelines and industrial equipment connection systems due to their excellent weldability and reliable mechanical strength. However, in the actual engineering procurement process, some common misconceptions often lead to improper material selection, increased costs and even risks to system safety. This article will analyze the common…

In petrochemical, power, natural gas transmission and refinery projects, engineers often encounter two welded steel pipe standards—ASTM A671 and ASTM A672—when selecting pressure pipe materials. The two share certain similarities in manufacturing methods, but there are distinct differences in base material sources, performance requirements and application fields. For procurement engineers, understanding the core differences between ASTM A671 and A672 not only helps select pipe materials correctly but also effectively reduces project operation risks. This article provides a detailed analysis from…

In industries such as petrochemical, power generation, natural gas transportation, and refineries, high-pressure pipeline systems impose extremely strict requirements on material strength, weldability, and long-term reliability. Steel pipes manufactured under the ASTM A671 standard have become an important choice for many high-pressure pipeline projects due to their excellent mechanical properties and stable welding performance. However, different projects vary in pressure levels, temperature environments, and corrosion conditions. Therefore, selecting the appropriate grade and class of ASTM A671 EFW welded pipe is…

The key updates to the 2025 Edition of the ASME IX Welding Code mainly focus on six aspects: clarification of tolerance rules, optimization of welding procedure qualification, additive manufacturing processes, adjustment of welding process variables, upgrading of non-destructive testing (NDT), and supporting technology upgrades. Details are as follows: Clarification of Tolerance Rules 1.New Engineering Judgment Acceptance Clause (QW-100 Subparagraph (f)) It is clarified that when dimensions, specifications, or other parameters are not given as maximum values, minimum values, or with…

Mastering the differences in global welding standards is a compulsory course for the industry: European EN standards mandate CE certification, the American AWS system is flexible and practical, and Chinese GB standards are accelerating their integration with international standards. Overview of the European Welding Standard System The European welding standard system is mainly formulated by the Comité Européen de Normalisation (CEN) and closely cooperates with the International Organization for Standardization (ISO) to form the EN ISO series of standards. These standards cover the entire process of…

In bridge, factory, energy, and heavy-load engineering projects, the low-temperature safety of structural steel often determines the long-term reliability of the project. Especially in high-latitude, cold, or areas with significant day-night temperature differences, focusing solely on strength is no longer sufficient. Impact toughness becomes the key indicator that truly affects the structure's ability to resist brittle fracture. This article, written by LONGMA with over 20 years of experience in structural steel pipe production and quality control, systematically analyzes the impact…

In large-scale infrastructure and industrial construction projects, the reliability of structural materials directly determines engineering safety and service life. With increasing bridge spans, higher loads in industrial buildings, and increasingly complex service environments for heavy-load structures, conventional structural steels can no longer meet comprehensive performance requirements. Thanks to its higher yield strength, excellent weldability, and stable low-temperature toughness, S355 high-strength steel has become a mainstream choice in the fields of bridge steel, industrial building steel structures, and heavy-load structural steel. As…

In large-scale steel structures, bridge engineering, pressure vessels, marine equipment, and other projects, welding performance is often more critical than nominal strength in determining the long-term safety of the structure. As a widely used high-strength structural steel in the European EN 10025 system, S355 steel is extensively employed in load-bearing welded structures due to its excellent strength-toughness balance. However, in practical engineering, many quality issues stem not from the material itself but from insufficient understanding of S355's welding performance, welding…

In structural steel selection and engineering procurement, the delivery condition determines the actual performance of the material on site. This article, written by LONGMA with 20+ years of manufacturing and quality-control experience, systematically introduces the performance parameters of S355K2 and S355K2+N, the key differences from S355J2 (s355k2 vs s355j2), and common ASTM equivalent references, helping procurement engineers better control risk and cost. What is S355K2? S355K2 is a non-alloy structural steel defined under EN 10025-2 (Material no. 1.0596). It belongs…

Russian welding seam standards usually adopt the State Standard of the Russian Federation (GOST) or the Technical Regulations of the Russian Federation (FZ). These standards specify requirements for welding processes, welding seam quality, welding materials, welding equipment, welding inspection and testing, etc. It should be noted that specific welding seam standards and requirements may vary by industry and product. Therefore, in practical applications, it is necessary to select applicable standards and requirements according to the actual situation. Overview of the…

In the EN 10025-2 standard system, the S355 series is one of the most widely used structural steels. However, even though they all belong to S355J2, different delivery conditions such as S355J2+N, S355J2+AR, and S355J2M result in significantly different performance and application scenarios. Many buyers focus only on the grade itself while ignoring how heat treatment/delivery conditions affect performance, weldability, impact toughness, and even the final product lifespan. This article analyzes the differences among the three from heat treatment methods,…

In global steel procurement and engineering projects, “S355J2 Equivalent” is one of the most frequently searched technical keywords. Many users also search specifically for: s355j2 equivalent astm、s355j2 us equivalent、s355j2 equivalent indian standard、s355j2 steel equivalent — often because cross-standard material comparison directly affects project safety, procurement compliance, and cost. This article organizes all mainstream equivalents of S355J2 under ASTM, ASME, AISI, EN, GOST, and Indian Standards, and provides detailed comparison tables so buyers can quickly confirm whether S355J2 meets their engineering…