When it comes to types and options of structural steel, it can be confusing. Structural steel is categorized separately for three main reasons. These are geometry, metal composition, and size. When most people think of structural steel, they think of I-beams. However, there are many other forms of structural steel.
The American Society for Testing and Materials (ASTM) developed the first structural steel standard. Standard A9 was the first standard for structural steel used in construction. This standard has been around since 1900, which is more than 100 years ago.
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Why Are There So Many Structural Steel Grade Standards?
You may be wondering why there are so many structural steel grades. You may also wonder why you should buy a certain grade when it is easier to buy steel of the same grade.
Common structural steel grades must meet a set of rules. These include, for example, corrosion resistance, mold growth, fire resistance, strength, and ease of processing. Although steel has an excellent strength-to-weight ratio, without standards it is impossible to determine the end result.
A572-50, made using hot rolling, is an example of a high-strength, low-metal structure. It also withstands a yield strength of at least 50,000 psi, which is another key point. With the right reading skills, you can tell whether it is an iron alloy or a steel alloy by looking at the number at the beginning and the grade.
If you know that the material is made in a standard way with standard ingredients. Then you can be sure of a standard and reliable result. At the end of the 19th century and the beginning of the 20th century, many people had this problem with steel and other things. This led to the establishment of many organizations whose job it was to set standards for production and materials. You can also look at ANSI and SAE, which are two other global steel standards.
Often, different companies have to follow different rules. When it comes to construction materials for structures, you will often see ASTM and EN numbers. Let’s talk about two of these standards.
ASTM Standards
The American Society for Testing and Materials (ASTM) is where the name comes from. It is the best organization in the world when it comes to standards. Anyone interested can join, but it is not compulsory. To avoid antitrust issues, less than half of the people in the standards-setting organization can produce materials.
ASTM was founded in 1898, predating groups and associations such as the IEC, DIN, ANSI, ISO, and AFNOR. ASTM International was founded by a group of engineers and scientists to help solve material problems in the then rapidly developing emerging railway industry.
It has five different ASTM world standards. They conclude:
- Iron and Steel
- Nonferrous Metals
- Ceramic, Masonry, and Concrete
- Miscellaneous Materials
- Subjects
- Materials for Particular Applications
- Deterioration, Corrosion, or Degradation
Many governments use ASTM guidelines to ensure product safety, market access, and health standards. Many groups require compliance with their standards when using certain materials, but ASTM does not actively require compliance with these standards. Governments, businesses, or stakeholders can also make such requirements through external contracts. The US government has issued many regulations that require strict compliance with ASTM standards.
ASTM Standards That Are Strictly Adhered to in the USA
- A36: It consists of 98% iron, 1.03% manganese, and a few other components. Depending on the industry in which it is used, there are various ways to increase the hardness of the steel. This grade is most often used when structural steel is used in large buildings.
- A500B: It is often used for square, round, or rectangular tubes made of cold-formed, welded, and seamless carbon steel. In the USA, it is mainly used for hollow structural sections.
- A572-50: These rules only apply to HSLA (high-strength low-alloy) steel. This type of steel is a common type. When you compare its strength to other types of steel, you will find that it requires less material.
- A588: It is also a type of HSLA steel. It is mainly used in building structures such as houses and bridges. However, it is different from the A572-50 standard. Because this type of steel also needs to be rust-proof in the air.
- A992: This is the standard for structural steel alloys. It is suitable for I-beams and wide flange beams. It is the most popular in the construction industry.
- A6-19: This is the industry standard for rolled structural steel plates, bars, sheet piles, and sections.
- A131-19: This is the standard for structural steel plates used in shipbuilding. The yield strength must be at least 34 KSI.
- A143: This is the standard for protecting hot-dip galvanized structural steel products from embrittlement.
- A148-20e1: This is the standard for steel castings. It includes carbon steel, alloy steel, and stainless steel. All castings must be heated by a specific method.
- A242-13: This standard covers HSLA steel sections, plates, and bars for welding, bolting, and riveting construction. They are used where weight is less of a concern and durability is more important.
Other I-beam Standards
Xinguangzheng can provide you with high-quality structural steel. The following are the I-beam standards we supply most often:
- A36
- A500B
- A572-50
- A588
- A992
In addition, there are other standards available. ASTM has developed regulations for carbon steel, formed steel, quenched and tempered alloy steel, high-strength low-alloy steel (HSLA), and non-rusting HSLA. All other standards that cover the use of structural steel from A0 to A500 include:
- A6-19
- A131-19
- A143
- A148-20e1
- A242-13
However, there are dozens of other standards, such as A1000 for hollow structural sections (HSS). When it comes to steel, ASTM international standards marked with an “A” are the same as all other structural steel standards. The A36 standard is probably one of the most popular standards that structural steel must meet. No matter what standard or type of structural steel you need, Xinguangzheng can provide it according to your requirements.
Start your project today with a tailored price estimate for your steel building.
European and CEN Standards
In the European Economic Area, steel must also comply with other regulations. Developments in the world economy have led to a situation where steel can meet several standards in some areas.
When you see different items, you may be wondering why they all have the “CE” mark. It’s like the one on some electronic products. It stands for “European Conformity,” and that’s what the CE mark means. It’s French for “Conformité Européenne,” the language used in Brussels, where the leaders of the European Union live.
The CE mark itself is not a standard, but it applies to standards that comply with the standards of the European Economic Area. These standards are not American standards. However, as construction materials come from all over the world, you may find that you have a choice between two different standards.
The European Committee for Standardization has developed a number of “EN” or European standard specifications that apply to steel.
- EN 10024
- EN 10034
- EN 10162
In addition, there are many standards for other types of structural steel. For example, the main standards for steel hardware, pipes, steel sheets, and sections or steel profiles:
- EN 1090
- EN 10025
- EN 10210
- EN 10219
- EN 14399
- EN 15048
But this is by no means a complete list of all the rules for steel. Since there are so many seemingly similar standards, is it possible to mix and match them?
Mixing Standards Is Not a Good Idea
Very often, people get their hands on a number of standards for steel. For example, standards such as A36 (no hardware specified) and A325 (hardware-specific)
You might think: “The steels look the same, so it should be okay!” From a physical point of view, they are the same in terms of tensile strength, etc., and they are very similar chemically. But shape and function are the biggest differences between them. If this sounds like something you’ve done, stop right there!
For example, the standard for grade 5 SAE bolts requires a finished hexagonal head. The A325 hexagonal head is heavier, so you think you’re safe as long as you find a grade 5 heavy hexagonal head. But you’re wrong again. The thread structure determines the strength of the skeleton steel. Not only that, they are designed for heavy hexagonal nuts, and both grade 5 and A325 meet different thread size standards.
Structural bolts must also meet specific standards in the ASTM standard. In particular, A307A and A307B bolts are designed to do their job. Both A307A and A307B have a minimum tensile strength of 60 ksi. A307B bolts can only be pulled apart by up to 100 ksi. If they are pulled that tightly, they will break at the head. Pipe fittings flanges use A307B nuts, which are designed to break before the flange does.
Grade 5 nuts can damage more expensive flanges. If too much pressure builds up, the pipe could even explode, endangering lives. If your structure needs to meet a specific standard, such as A36, it is best to choose a standard that matches it, such as A307 or A325.
Summary
It can be difficult and costly to buy the right grade of structural steel. The above are some of the most commonly used grades of structural steel. Hopefully, this information has helped you to better understand them. Even if you know how structural steel standards are set. Without engineering guidance and experience, it can be difficult to know what you need. Don’t worry, we can help you with these issues.
For many years, Xinguangzheng has been meeting the world’s demand for structural and decorative steel. We can source any metal you need from anywhere in the world and deliver it to you in the shortest possible time. Contact us today for the help and materials you need.
