The top 20 galvanized steel pipe symbols that you must know

The top 20 galvanized steel pipe symbols that you must know

Each galvanized steel pipe symbol represents a unique meaning. They help project owners and technicians identify and purchase the appropriate type of steel pipe. They can be symbols that represent technical specifications, standards, chemical and mechanical properties, etc. However, because there are many symbols, we often get confused. To help everyone understand these symbols, Bao Tin Steel would like to provide the information below.

Galvanized steel pipes currently have about 20 common symbols. Depending on the manufacturer’s brand, they are often printed directly on the tube body. As mentioned, these symbols represent diameter, thickness, length, manufacturing standards, etc. To make it easier for everyone to imagine, we divide them into three groups, including:

The group shows the dimensions of galvanized steel pipes.

DN (mm) – Nominal diameter

Nominal diameter DN stands for Diameter Nominal or Nominal Diameter. It is understood as the nominal pipe size or the approximate inside diameter of the pipe measured in millimeters.

The DN symbol does not represent the exact diameter of the pipe. The actual size will vary slightly. This is only an approximate number, so technicians can easily select and use system pipes. To determine DN, we can apply the formula:

NPS – Nominal Outside Diameter

NPS (or NS) stands for Nominal Pipe Size, which is the North American standard pipe size designation system, with units of measurement being inches (“). This is not the exact outside diameter of the tube. Like the nominal inside diameter (DN), this is only an approximate size of the pipe. It used to help us easily choose pipes for our system.

For example, when saying galvanized steel pipe 1 NPS, This means that the galvanized pipe has an outside diameter of 1.315 inches.

Φ – Outside diameter of the pipe

Φ is similar to NPS; it is a parameter indicating the outside diameter of steel pipes. The big difference here is that the unit is millimeters, not inches. In addition, depending on production standards, pipes will have different actual outside diameters. And phi is just the approximate outside diameter.

Specifically, if the pipe is manufactured according to ASME standards, DN15 will have an outside diameter of OD = 21.34 mm. But when buying pipes or talking about their systems, people often round them up and call them non-21 steel pipes.

SCH – Pipe wall thickness

This is an abbreviation for the word schedule, used to determine the thickness of the pipe wall. The smaller this index, the thinner the tube wall, and vice versa, the larger the number, the thicker the tube wall. This thickness is also divided into levels from thin to thick, such as SCH5, SCH10, SCH20, SCH30, SCH40, SCH60, SCH80, SCH120, SCH160,…

Inch (“) – Unit of measurement according to the American measurement system

Inches are sometimes abbreviated as (in) or with double quotes (“). We can easily see these indicators on steel pipe bodies such as 1/2″, 2″, 3/4″, and 3”,…. To make it easier to use, people convert inches to mm or vice versa (depending on the system). You can convert the resulting figures using the following conventions:

• 1 inch = 25,4 mm
• 1 mm = 0,03937 inch
• 1 foot = 12 inches
• 1 yard = 3 feet = 36 inches

The group represents the production standards for galvanized steel pipes.

Galvanized steel pipes are produced according to many different standards. Each standard will have its symbols and names. Current popular standards include:

ASTM – American Standard

ASTM is the acronym for the American Society for Testing and Materials. This standard provides specific instructions and requirements during the production of galvanized steel pipes. These include requirements for temperature, chemicals, technical parameters, the minimum thickness of the plating layer, etc. Along with that, there are methods to evaluate and check the quality of galvanized pipes before bringing them to market.

JIS – Japanese Industrial Standard

JIS standards stand for Japanese Industrial Standards. This standard regulates the chemical composition, mechanical properties, dimensional tolerances, and thickness of the zinc coating. Steel pipes produced according to this standard are usually of high quality, durable, and less susceptible to corrosion.

BS –  British Standard

BS is the abbreviation for British Standard. It identifies specific requirements when producing galvanized corrugated iron pipes. including quality of components (carbon content, alloys, other chemical substances), size and thickness, plating method, durability, plasticity, and adhesion of the zinc coating.

Currently, Bao Tin Steel is also providing Hoa Phat galvanized pipes according to ASTM, JIS standards, etc. Not only that, we ensure that our prices are always the most competitive. If you have any needs or need advice, call us immediately! Hotline: 0932 059 176.

Group of technical symbols for galvanized steel pipes

This group of symbols helps buyers understand the components, characteristics, dimensions, and weight of galvanized pipes in particular and steel pipes in general. They can be printed on the pipe body or the steel mark accompanying each pipe bundle.

About chemical composition

We all know that iron (Fe) is the main ingredient in steel pipes. However, there are still a few other ingredients, such as phosphorus (P), sulfur (S), and carbon (C). In the standard table, they will be:

• Pmax: Maximum phosphorus content
• Smax: Maximum sulfur content
• Cmax: Maximum carbon content

About the size of galvanized steel pipes

• D: Outside diameter of steel pipe (mm);
• T: Thickness of steel pipe (mm);
• L: Length of steel pipe (mm);
• A: Density of pipe component materials;
• M: Mass per unit length of steel pipe (kg/m)

Regarding mechanical properties

• ReH: Yield limit (MPa). This is the maximum pressure value that galvanized pipes can withstand before being permanently deformed.
• Rm: Tensile strength limit (MPa). This is the maximum stress value that galvanized round pipes can withstand before breaking.
• A: Elongation of steel pipe (calculated in % compared to the original length). This symbol is also known as relative elongation. It helps evaluate the plastic deformation ability of pipes.
• S: Stress generated during hydraulic testing (MPa).
• P: Compression test constant. This constant evaluates the load-bearing capacity of steel pipes.

Above are the most easily encountered galvanized steel pipe symbols. Bao Tin Steel hopes the above information will be really useful to everyone. If you need support, please contact us immediately via our hotline: 0932 059 176.

Tiger Steel is a branch of Bao Tin Steel.