In global steel engineering projects, S355J0 equivalent is one of the most frequently searched technical topics by procurement engineers and design institutes. As a steel pipe manufacturer with 20+ years of production experience, LONGMA fully understands the uncertainties of cross-standard material sourcing. This article provides a complete analysis based on authoritative data, standard clauses, and test evidence to help you accurately determine material equivalence, reduce project risks, and improve procurement efficiency. S355J0 Equivalents in International Standards (Core Comparison Table) The following…

Tungsten Inert Gas (TIG) Welding is an arc welding process that generates heat between a non-consumable electrode and the workpiece. The electrode rod, weld pool, arc, and the heated area adjacent to the workpiece are all shielded by a gaseous medium to prevent atmospheric contamination. This shielding is provided by a single gas or gas mixture, which must offer full protection—even minute air infiltration can contaminate the weld bead. As a non-consumable electrode inert gas shielded welding process, TIG/GTAW operates…

S235JR is one of the most widely used non-alloy structural steels in EN 10025-2. Whether in steel structure construction, pressure pipeline frames, mechanical support manufacturing, or bridge and steel platform assembly, welding is involved in almost every processing stage. Therefore, understanding S235JR weldability, mastering suitable welding electrodes, and developing a scientific process plan are key to ensuring safety and cost-efficiency in engineering projects. This guide analyzes S235JR welding from multiple perspectives—including metallurgical principles, welding risks, filler materials, electrode selection, testing…

The core requirements for grinding after welding include ensuring the weld surface is smooth and flat, removing slag and defects, controlling the base metal removal amount to no more than 5% of the thickness or 0.2mm, aligning the grinding texture with the weld direction, and adjusting specific operations according to the welding type (e.g., thermit welding) and material (e.g., stainless steel). Main Purposes of Grinding After Welding Eliminate Surface Defects: Remove slag, spatter, porosity, undercut, and other flaws to prevent…

As one of the most commonly used non-alloy structural steels in the EN 10025-2 standard, S235JR occupies an important position in fields such as building structures, bridges, machinery manufacturing, petrochemicals, and transmission pipelines due to its stable mechanical properties, good weldability, and wide processing adaptability. For purchasers, selecting the most suitable S235JR material among different product forms is a key issue related to cost, quality, and safety. This article will comprehensively analyze the S235JR product system from four dimensions: performance…

The presence of shielding gas acts like an invisible barrier, blocking the intrusion of oxygen and moisture from the air into the weld seam. If the barrier is stable, an oxide film will not easily form on the metal surface, the purity of the weld pool will be improved, and ultimately the strength and appearance of the weld seam will be more reliable. There are many factors involved, but the core lies in three key aspects: gas type, gas purity…

In structural steel procurement, S235JR is one of the most widely used non-alloy structural steels due to its stable performance and excellent processability. It is commonly applied in steel structures, mechanical components, infrastructure, and pipe systems. However, different projects have different requirements for strength, ductility, and safety factors. Therefore, customers' most frequent questions usually include: What is the S235JR tensile strength? Does the S235JR yield strength meet the project requirements? Do the S235JR mechanical properties vary with thickness? How does the…

Vacuum heat treatment refers to a heat-treating process in which the workpiece is heated to the required temperature in a vacuum atmosphere of 10⁻¹~10⁻² Pa, followed by cooling in different media using different methods. Vacuum heat treatment is recognized in the modern heat-treatment industry as an efficient, energy-saving, and pollution-free clean heat-treatment technology. Parts treated by vacuum heat treatment feature no oxidation, no decarburization, degassing, degreasing, excellent surface quality, minimal deformation, high comprehensive mechanical properties, and stable reliability. Therefore, vacuum…

In the fields of steel structures, pressure components, bridge engineering, and pipeline manufacturing, engineers often need to choose among S235JR, S275JR, S355JR, and Q235, four commonly used structural steels. However, different projects have different requirements for strength, weldability, impact toughness, and cost. So which grade is the most reliable choice? This article analyzes the topic from five dimensions: standards, chemical & mechanical properties, testing methods, application scenarios, and procurement risk control—helping you clearly determine which steel grade best fits your…

In the process of steel procurement and engineering material selection, questions such as “Which Werkstoff number corresponds to S235JR?” or “Why do some documents show 1.0037 while others show 1.0038?” are very common. Properly understanding the relationship between the S235JR steel number and the historical/modern numbering systems is essential for technical specification review, MTC (Mill Test Certificate) verification, and cross-standard comparison (DIN, EN, JIS, ASTM). This article analyzes the topic from five perspectives: numbering origin, standard evolution, technical differences, inspection…

Visual inspection is a commonly used welding quality inspection method. Its main purpose is to check the surface quality of welding joints, including weld shape, dimensions, undercut, depression, porosity, etc. Visual inspection can be carried out by the naked eye or with the help of magnifying glasses, as well as auxiliary tools such as laser rangefinders and optical measuring instruments. This method can effectively detect surface defects of welding joints but cannot identify internal defects. Overview of Core Standard Systems…

Among global structural steel standards, EN 10025 S235JR is one of the most widely used baseline grades in engineering, steel structure fabrication, and machinery manufacturing. Since different projects require different levels of toughness, weldability, and load-bearing capacity, choosing the correct delivery condition—such as +AR / s235jr ar or +N / s235jr+n—directly affects engineering safety, welding quality, and procurement risk control. Based on the EN standard framework, this article analyzes EN 10025-2 S235JR from five angles: delivery conditions, testing methods, service condition selection, quality…

The performance of welding defects on radioscopic films is a key basis for welding quality evaluation. Various common welding defects have distinct image characteristics and corresponding standard specifications on the films. There are 18 typical defects, including uneven welds, root incomplete fusion, insufficient reinforcement, root weld bead, external undercut, internal undercut, root depression, burn-through, isolated slag inclusion, linear slag inclusion, internal incomplete fusion, inner-side incomplete fusion, porosity, chain porosity, bead inclusion, transverse crack, centerline crack, and root crack. By systematically…

In engineering material selection and procurement, S235JR and S275JR are commonly used non-alloy structural steels defined in EN 10025-2. At first glance, they seem similar in application, but they differ clearly in strength grade, chemical composition limits, mechanical properties, and inspection requirements—differences that directly impact structural safety, weldability, and low-temperature performance, determining whether they can be considered “equivalent alternatives.” Key Performance Comparison at a Glance   Parameter S235JR S275JR Nominal minimum yield strength 235 MPa 275 MPa Tensile strength Rm (typical range) ~360–510…

In engineering procurement and structural design, one of the most frequently asked questions is:Can the European standard steel S235JR (EN 10025-2) be interchanged with the American standard ASTM A36? The short answer: They are similar in most general structural applications, but not strictly identical. There are key differences in mechanical properties, delivery conditions, and impact toughness requirements, which must be verified through testing and certification to minimize procurement risk. Differences in Standards and Definitions S235JR (EN 10025-2) Non-alloy structural steel with a…