Boiler tubes are hollow steel materials with openings at both ends and a length greater than their circumference. Based on their manufacturing process, they are classified into seamless steel tubes and welded steel tubes.
As critical components of boilers, selecting the right boiler tubes is essential for enhancing service life and operational efficiency. The quality of boiler tubes directly impacts boiler performance, influencing both industrial production and everyday applications.
General Boiler Tube Model Chart
Model |
Material |
Diameter(mm) |
Wall Thickness(mm) |
Length(m) |
||
20G |
Iron |
51 |
5.5 |
6-12 |
||
20MnG |
Iron |
51 |
5.5 |
6-12 |
||
25MnG |
Iron |
51 |
5.5 |
6-12 |
||
15CrMoG |
Iron |
51 |
5.5 |
6-12 |
||
12Cr1MoVG |
Iron |
51 |
5.5 |
6-12 |
||
12Cr2MoG |
Iron |
51 |
5.5 |
6-12 |
||
10Cr9Mo1VNb |
Iron |
51 |
5.5 |
6-12 |
||
1Cr18Ni9Ti |
Stainless Steel |
51 |
5.5 |
6-12 |
||
1Cr18Ni9Ti |
Stainless Steel |
76 |
6.0 |
6-12 |
||
1Cr18Ni9Ti |
Stainless Steel |
89 |
6.0 |
7-12 |
General Boiler Tube Size Chart
Material |
Diameter(mm) |
Wall Thickness(mm) |
Iron |
51 |
5.5 |
Iron |
57 |
6.0 |
Iron |
60 |
6.0 |
Iron |
63.5 |
8.0 |
Iron |
76 |
7.0 |
Iron |
89 |
8.0 |
Stainless Steel |
51 |
5.5 |
Stainless Steel |
76 |
6.0 |
Stainless Steel |
89 |
6.0 |
General Boiler Tube Parameter Chart
Model |
Main Material |
Tensile Strength(MPa) |
Yield Strength(MPa) |
Elongation(%) |
Hardness(HB) |
20G |
Iron |
410-550 |
≥245 |
≥24 |
≤179 |
20MnG |
Iron |
415-550 |
≥245 |
≥22 |
≤179 |
25MnG |
Iron |
450-600 |
≥275 |
≥22 |
≤217 |
15CrMoG |
Iron |
440-640 |
≥235 |
≥21 |
≤207 |
12Cr1MoVG |
Iron |
470-640 |
≥255 |
≥21 |
≤241 |
12Cr2MoG |
Iron |
450-600 |
≥280 |
≥20 |
≤255 |
10Cr9Mo1VNb |
Iron |
585-780 |
≥415 |
≥20 |
≤255 |
1Cr18Ni9Ti |
Stainless Steel |
≥520 |
≥205 |
≥40 |
≤187 |
General Boiler Tube Specification Chart
Material |
Range |
Iron |
Φ51x5.5-6.0x6-12m |
Iron |
Φ57x6.0-7.0x6-12m |
Iron |
Φ60x6.0-7.0x6-12m |
Iron |
Φ63.5x8.0x6-12m |
Iron |
Φ76x7.0-8.0x6-12m |
Iron |
Φ89x8.0-10x7-12m |
Stainless Steel |
Φ51x5.5-6.0x6-12m |
Stainless Steel |
Φ76x6.0-8.0x6-12m |
Stainless Steel |
Φ89x6.0-8.0x7-12m |
Key Factors for Selecting Boiler Tubes
Choosing the right boiler tube is crucial for ensuring efficient and safe boiler operation. The following factors should be considered when selecting boiler tubes:
1. Flow Rate
The flow rate should be determined based on the required heat output and water circulation volume. A flow rate that is too high or too low can negatively impact the boiler’s performance and efficiency.
2. Pressure
Boiler tubes must withstand the maximum operating pressure and temperature of the system. The material's load-bearing capacity should also be taken into account. Selecting tubes with insufficient pressure resistance may lead to pipe bursts, while excessive pressure ratings can increase the risk of ruptures.
3. Material
The choice of material should be based on fuel type, medium, pressure, and temperature. Common materials include:
Carbon steel – Suitable for lower-temperature and pressure applications.
Alloy steel – Offers enhanced strength and heat resistance.
Stainless steel – Provides excellent corrosion resistance for high-temperature environments.
4. Safety Features
Boiler tubes must be equipped with safety valves and pressure-reducing valves to maintain safe operation and prevent excessive pressure buildup.
5. Size
The tube size should be selected based on the above factors. Larger tubes generally increase costs, while smaller tubes may be more suitable for compact boiler systems with lower flow requirements.
Conclusion
Selecting the appropriate boiler tube involves careful consideration of flow rate, pressure, material, and size to ensure safe and efficient operation. In practical applications, choosing the right specifications based on specific system requirements helps optimize performance and extend the boiler’s service life.