[admin]

In the selection process of the high carbon steel tube, the matching principle of wall thickness, outer diameter and material is the key to ensuring the safe and reliable operation of the pipeline.

I. Principles for Wall Thickness Selection

Wall thickness is an important parameter that determines the load-bearing capacity, corrosion resistance and service life of pipelines. According to relevant standards and engineering practices, the selection of wall thickness should follow the following principles:

Pressure resistance requirement: The pressure that the pipeline can withstand is an important factor in determining the wall thickness. According to standards such as GB/T 9711.1 and GB/T 9711.2, the wall thickness should meet the strength requirements of the pipeline under working pressure. For example, when conducting strength verification using the ASME B31.3 formula, the fatigue stress caused by vibration loads needs to be considered additionally. It is recommended to reserve a strength redundancy of 15%-20%.

2. Corrosive environment: The environment in which the pipeline is located (such as pH, oxidizability, etc.) will affect its corrosion rate. In highly corrosive environments, carbon steel pipes or stainless steel pipes with larger wall thickness should be selected to extend their service life.

3. Economy: Under the premise of meeting safety and service life requirements, a reasonable wall thickness should be selected as much as possible to reduce material consumption and costs. Excessive wall thickness will lead to resource waste, while too little wall thickness may sacrifice the safety of the structure.

4. Standard Specifications: National and industry standards (such as GB/T 3090-2000) have clear regulations on the wall thickness of steel pipes, which must be strictly followed to ensure the quality of pipelines and the safety of the project.

Ii. Matching of Outer Diameter and wall thickness

The matching relationship between the outer diameter and the wall thickness directly affects the pressure-bearing capacity, weight and cost of the pipeline. Steel pipes of different outer diameters correspond to different recommended wall thickness ranges to ensure their performance under specific working conditions.

1. Recommended wall thickness range: According to the recommended wall thickness table provided by Parker Hannifin Corporation, steel pipes with different outer diameters have corresponding recommended wall thicknesses. For example:

The recommended wall thickness for steel pipes with an outer diameter of -4 inches is 0.75 inches.

For steel pipes with an outer diameter of -6 inches, the recommended wall thickness is 1 inch.

For steel pipes of -8 inches and above, the recommended wall thickness is 1.5 inches.

2. Relationship between wall thickness and weight: The greater the wall thickness, the greater the weight of the steel pipe. For example, for a steel pipe with an outer diameter of 0.028 inches and a wall thickness of 0.035 inches, the weight is 10,300 pounds, while for a wall thickness of 0.049 inches, the weight is 9,700 pounds. Therefore, on the premise of meeting the strength requirements, a smaller wall thickness should be selected as much as possible to reduce costs.

3. Matching of wall thickness and diameter: In actual engineering, the diameter and wall thickness of steel pipes need to be reasonably matched. For example, for a pipe with an outer diameter of 16 millimeters, its wall thickness can be 2.5 millimeters, 3 millimeters or 3.5 millimeters. The wall thickness of a pipe with an outer diameter of 25 millimeters can be 3.5 millimeters, 4 millimeters or 4.5 millimeters.

Iii. Material Selection and Matching

The choice of material directly affects the corrosion resistance, strength and service life of the pipeline. According to different usage environments, appropriate materials should be selected.

1. Common carbon steel: It is suitable for dry environments, has a relatively low cost, but is not corrosion-resistant.

2. Stainless steel (such as 304/316 series) : Suitable for acidic and alkaline environments, it has good corrosion resistance, but the cost is relatively high.

3. Alloy steel (such as 15CrMo) : Suitable for high-temperature working conditions, it features high strength and heat resistance.

4. Matching of material and wall thickness: Steel pipes of different materials have different strengths and toughness. Therefore, when choosing the wall thickness, the characteristics of the material should be taken into account. For instance, the wall thickness of stainless steel pipes is usually thicker than that of carbon steel pipes to ensure their stability in corrosive environments.

Iv. Comprehensive Considerations

In actual engineering, the selection of wall thickness, outer diameter and material also needs to take into account multiple factors comprehensively to ensure the overall performance of the pipeline system.

1. Structural and environmental factors: For heavy industrial building structures, large-span structures, and structures directly subjected to dynamic loads, seamless steel pipes with good comprehensive performance should be selected. For structures operating under low-temperature conditions, steel pipes with good resistance to low-temperature brittle fracture should be selected. For open-air structures or environments where harmful media act, steel pipes with strong corrosion resistance should be selected.

2. Economy and feasibility: Under the premise of meeting the flow and pressure requirements, factors such as the cost of the pipe material, installation difficulty and maintenance convenience should be comprehensively considered to select an economically reasonable pipe diameter and wall thickness.

3. Construction and installation requirements: The connection method and installation requirements of the steel pipes will also affect their selection. For example, the wall thickness of the pipe for hot-melt installation should not be less than 2.0mm.

V. Summary

The selection of high carbon steel tube should comprehensively consider the matching relationship between wall thickness, outer diameter and material, and be combined with specific engineering requirements and usage environment. By rationally choosing the wall thickness, outer diameter and material, the safety, reliability and economy of the pipeline can be ensured. In practical applications, national standards and industry norms should be strictly followed to ensure the long-term stable operation of the pipeline system.

http://www.torichsteel.com
TORICH

[Author]

Posts