European Standards for Materials and Welding Materials

Since the European Standard (EN) has been enforced by the European Union and its member states as the national standard of the country, it has played a positive reference and reference for the application and revision of standards in China and other countries. At present, European standards are increasingly recognized internationally, and most of them have been equivalently equivalently converted into international standards (ISO). This article provides an overview of the European standards for some iron-based materials and welding filler materials from the revision, content, application and corresponding ISO standards.

Development of European standards for some raw materials and welding materials

Most of the European standards for raw materials and welding consumables were drafted and developed by the European Committee for Standardization in 1992-1998, and were eventually voted by the member states. Once adopted, the original national standards of the standard will be abolished and a unified European standard will be implemented. From the content point of view, its source consists of three parts, part of which is the former European Standard (EU). The EU standard is a series of standard technical documents formed by the major member states of the European Union in the historical process of 40 or 50 years. It is more familiar and easy to be accepted by all member states; for example, the former European standard EU20 (the concept and classification of steel) is transformed into the European standard EN10020 (the concept and classification of steel). The second part is the German Industrial Standard (DIN). Due to Germany's economic status in the European Union and its outstanding performance in metallurgy and welding technology, the content of the DIN standard is taken as the current European standard. For example, the German standard DIN8575 (gas-shielded welding wire for heat-strength steel) is converted into the European standard EN12070 (gas-shielded welding wire for heat-strength steel); the third part is to equivalently adopt the existing standard in ISO as the European standard, such as The international standard ISO 13916 (pre-heating during welding, measurement of interlayer and protection temperature) is converted to the European standard EN ISO 13916 (preheating during welding, measurement of interlayer and protection temperature). From the perspective of existing European standards, the existing ISO standards are adopted or referenced as much as possible, and the marking methods and contents are consistent with the ISO standards, which are more detailed and specific than the corresponding ISO standards.

Introduction to the European Standards for some raw materials

Common standards for iron-based materials that can be welded in European standards are as follows:

Take the commonly used non-alloy structural steel and pressure vessel steel as an example, compare the EN standard and the ISO standard from the symbol mark and chemical composition:

Both the standard number + additional symbol marking method is used, and the material marking reflects the material's use, strength performance, quality grade, and supply status. For example, EN10025 S235J2G3, S-structure steel, yield strength below 235-16mm The lowest value is 235Mpa, J2G3—quality level (impact power and delivery status), while in ISO4995 HR235 B, the lowest value of HR-heating state and 235-yield strength is 235Mpa and B-quality grade.

The chemical composition and mechanical properties are basically the same, but the European standard is more detailed. For example, in the standard for strength steel, the European standard lists the lowest yield strength and tensile strength of the material at different supply thicknesses. Value, while international standards only give a range.

Introduction to European Standards for Common Welding Filling Materials (Table below)

For example, manual arc welding of carbon steel and fine-grained structural steel and heat-strength steel is compared with ISO standards from symbol marking and application:

From the standard of carbon steel and fine-grained structural steel welding rods, the marking format is the same, but the meanings are not exactly the same, such as EN-E499 E38 0 RC, E-manual arc welding method symbol, 38-minimum yield of deposited metal The strength is 380Mpa, the minimum elongation is 20c/o, the 0-0°C V-notch impact energy is at least 47J, RC-coat type; ISO2560 E43 2 RC E-manual arc welding method symbol, 43-welded metal The tensile strength is 430-510Mpa, the minimum elongation is 22c/o, and the 0-0°C V-notch impact energy is at least 28J, RC-drug type. From the standard of heat-strength steel electrode, the marking format is the same. Only the chemical composition mark of the deposited metal is CrMo1 in the EN standard and 1CrMo in the ISO standard.

Throughout the marking method of European welding filler materials, the regularity is composed of deposited metal properties or chemical composition + filling material type or code, such as:

EN440 G 46 6 M G3Si1, 46 6— Gas shielded welding deposited metal properties, M G3Si1—mixed gas, G3Si1 welding wire. This way, from the symbol mark, it can be roughly seen whether the material selection is reasonable.

Understanding and application of European standards

European standards have the characteristics of fine classification and strong pertinence. Pay attention to the preconditions in application. For example, the welding rod standard for welding structural steel by manual arc welding is EN499, EN757, EN499 is applicable to the strength structure of material yield strength ≤500Mpa. Steel is used, and EN757 is suitable for steels of strength structural strength with material yield strength >500Mpa. In addition, while the European standards are being formulated, various academic institutions or authoritative departments have developed a number of material use specifications or procedures for the development of materials for cold processing or thermal processing technical regulations, such as the German steel material specification SEW088 (on material melting Welding welding manufacturing procedures). If it is not a special order, the material can be formulated according to SEW088 during welding.