Carbon Steel Seamless Pipes Specifications

Carbon steel seamless pipes are a type of steel pipe with carbon as the main alloying element, which is widely used in machinery, construction, oil and gas, automobiles and other fields. Compared with welded steel pipes, carbon steel seamless pipes have the characteristics of high strength, wear resistance, corrosion resistance, defect-free, and high temperature resistance, so they have a long service life and can withstand greater pressure and heavy loads.

The size specifications of carbon steel seamless pipes are mainly composed of outer diameter, wall thickness and length, and the values of different standard systems (such as national standards and American standards) are different. The following is an analysis of key parameters.

Outer diameter range

The specifications of large-diameter carbon steel seamless pipes generally refer to pipes with an outer diameter greater than 159mm, and commonly used specifications include φ219mm, φ245mm, φ273mm, φ325mm, etc.

The specifications of small-diameter carbon steel seamless pipes generally refer to pipes with an outer diameter less than 159mm, and commonly used specifications include φ114mm, φ108mm, φ89mm, φ73mm, etc.

The outer diameter of carbon steel seamless pipes has various specifications, such as DN15~DN600, etc. In a wider range, the outer diameter of carbon steel seamless pipes is usually between 6mm and 426mm.

Wall thickness grade

In international standards, the calculation formula for the wall thickness of carbon steel seamless pipes is:

S=(D-d)/2, where S represents wall thickness, D represents outer diameter, and d represents inner diameter.

International standards specify the wall thickness of carbon steel seamless pipes of different types, such as ASTM A106/A106M, ASTM A179/A179M, etc. In these standards, the wall thickness of the pipe has specific requirements and ranges, and the required wall thickness is different according to different uses and service conditions. For example, the ASTM A106 standard stipulates that the commonly used seamless steel pipe wall thickness is SCH40, SCH80, STD, XS, XXS, etc., and the standard values and allowable deviations of these wall thicknesses are also defined in detail.

Taking the American standard as an example, SCH40 (standard wall thickness) and SCH80 (thickened wall thickness) are typical classifications. For example, the wall thickness of DN50 steel pipe SCH40 is 3.91mm, and that of SCH80 is 5.54mm (data source ASTM A106).

Length standard

The length of carbon steel seamless pipes is generally 6 meters, 9 meters, 12 meters, etc.

The common seamless pipe lengths are 5.8m, 6m, and 11.8m, and can also be customized according to customer needs.

Carbon steel seamless pipe specification and weight table

The following table shows the specifications and weights of commonly used carbon steel seamless pipes for reference only.

Common carbon steel seamless pipe specifications

1. DIN1629/DIN2448 (German standard)

Outer diameter range: 6-426mm

Wall thickness range: 1-40mm

Application: Suitable for general purposes, such as conveying fluids, gasoline, air, etc.

2. ASTM A106/A53/API 5L (American standard)

Outer diameter range: 21.3-914.4mm

Wall thickness range: 2-50mm

Application: Suitable for high temperature and high pressure occasions, such as oil, natural gas, etc.

3. JIS G3454/G3455/G3456 (Japanese standard)

Outer diameter range: 15.9-114.3mm

Wall thickness range: 2-14mm

Application: Suitable for conveying low temperature fluids, liquefied gas, etc.

4. GB/T 8162/8163 (bid)

Outer diameter range: 10-426mm

Wall thickness range: 2-60mm

Application: Applicable to structures, machinery, automobiles, pressure vessels and other fields.

5. EN10210-1/EN10216-1/EN10297-1 (European standard)

Outer diameter range: 21.3-711mm

Wall thickness range: 2-100mm

Application: Applicable to construction, machinery, automobiles, air conditioners, boilers and other fields.

Selection and application

1. High-pressure fluid transportation

For example, oil and natural gas pipelines, steel pipes with a wall thickness of ≥6mm are required to ensure pressure bearing capacity.

2. Pipes for mechanical structures

For example, automobile transmission shafts, precision seamless pipes with an outer diameter of 50-150mm and a wall thickness of 3-8mm are commonly used.

3. High temperature environment

It is necessary to add alloy elements such as chromium and molybdenum (such as P11/P22 material), and the working temperature can reach above 450℃ (according to ASTM A335).

Summary

The size and specifications of carbon steel seamless pipes should follow certain principles, such as selecting the appropriate outer diameter and wall thickness according to the requirements of the conveying medium, selecting the corresponding carbon steel seamless pipe specifications considering the pressure level of the pipeline system, and selecting the appropriate length in combination with the engineering design requirements. In addition, the production and application of carbon steel seamless pipes mainly follow specific national or international standards.