Customization:	Available
Application:	Automotive Industry, Chemical Industry, Food Industry, Oil and Gas Industry, Pharmaceutical Industry
Certification:	CE, ISO9001

Specification	T11	T12	T22
Standard	ASTM A213 / ASME SA213	ASTM A213 / ASME SA213	ASTM A213 / ASME SA213
Outer Diameter Range	Usually 12.7 - 273.05 mm	Usually 12.7 - 273.05 mm	Usually 12.7 - 273.05 mm
Wall Thickness Range	Varies based on application, typically 1.65 - 12.7 mm	Varies based on application, typically 1.65 - 12.7 mm	Varies based on application, typically 1.65 - 12.7 mm
Tube Length	Customizable, commonly 3 - 12 m	Customizable, commonly 3 - 12 m	Customizable, commonly 3 - 12 m

Property	T11	T12	T22
Yield Strength	≥ 205 MPa	≥ 170 MPa	≥ 205 MPa
Tensile Strength	415 - 585 MPa	380 - 515 MPa	485 - 655 MPa
Elongation	≥ 30%	≥ 30%	≥ 20%
Impact Resistance	Good at normal temperatures. Can be enhanced with appropriate heat treatment.	Good at normal temperatures. Can be enhanced with appropriate heat treatment.	Good at normal temperatures. Can be enhanced with appropriate heat treatment.
Fatigue Resistance	Generally better than welded tubes due to the absence of weld seams, which are potential sites for crack initiation.	Similar advantage over welded tubes in terms of fatigue resistance.	Also shows improved fatigue resistance compared to welded counterparts.

Process Step	Details
Billet Preparation	High - quality steel billets are selected. These billets are usually made from continuously cast steel, ensuring uniform chemical composition and structure.
Piercing	The billet is heated to a suitable temperature (around 1100 - 1250°C) and then pierced using a piercing mill. A mandrel is inserted into the heated billet, which is rotated and pushed through a set of rolls, forming a hollow tube.
Rolling	The pierced tube is further processed through a series of rolling mills. This process refines the grain structure, improves the dimensional accuracy, and enhances the mechanical properties of the tube. Different types of rolling mills, such as stretch - reducing mills or mandrel mills, can be used depending on the final product requirements.
Heat Treatment	To optimize the mechanical properties, the seamless tube may undergo heat treatment processes such as annealing, normalizing, or quenching and tempering. Annealing is often used to relieve internal stresses, improve ductility, and enhance the overall quality of the pipe.
Quality Inspection	Stringent non - destructive testing methods are employed, including ultrasonic testing to detect internal defects, eddy current testing to check for surface and near - surface flaws, and hydrostatic testing to ensure pressure - tightness.

Aspect	Performance
Overall Heat Transfer Coefficient	Similar to finned tubes in terms of the base tube's contribution to heat transfer. However, without fins, it may have a lower overall coefficient in some applications. But in scenarios where the fluid has high heat transfer coefficients on its own, the seamless tube can still perform well.
Efficiency	In applications where the focus is on the tube's internal heat transfer (e.g., in some heat exchangers with high - velocity fluids), the seamless construction can contribute to efficient heat transfer due to its smooth inner surface, reducing flow resistance and promoting better heat transfer by convection.

Environment	Performance
General Industrial Atmosphere	Good corrosion resistance due to the presence of chromium and molybdenum in the alloy. Forms a protective oxide layer on the surface.
Steam - containing Environments	Resistant to steam corrosion, making them suitable for use in boilers and steam - related heat transfer applications.
Mildly Corrosive Fluids	Can withstand corrosion from mildly acidic or alkaline fluids. However, in highly corrosive media, additional corrosion protection measures such as coatings or linings may be required.

Industry	Applications
Power Generation	- Boiler tubes in coal - fired, gas - fired, and oil - fired power plants, where high - temperature and high - pressure steam is transported. - Heat exchangers for pre - heating water or steam, as the seamless structure reduces the risk of leakage.
Chemical	- Transportation of various chemical fluids in reactors and processing units, especially those where leak - tightness is crucial. - Heat exchangers for cooling or heating chemical substances.
Petrochemical	- Pipelines for transporting oil, gas, and refined products within refineries. - Heat recovery systems in petrochemical processes.
Mechanical Engineering	- Hydraulic systems where high - pressure fluids are conveyed. The seamless construction can better withstand the high pressures without the risk of weld - related failures.

Control Measure	Description
Raw Material Inspection	Thoroughly test the chemical composition and mechanical properties of incoming steel billets. Ensure compliance with ASTM A213 standards.
In - process Monitoring	Continuously monitor the temperature, rolling forces, and dimensional accuracy during the manufacturing process. Use non - destructive testing methods at intermediate stages to detect any potential defects.
Final Product Testing	Conduct comprehensive tests, including non - destructive testing (such as ultrasonic testing, eddy current testing), hydrostatic testing, tensile testing, and hardness testing. Products must meet all relevant international standards, and may obtain certifications such as ISO 9001 and API (American Petroleum Institute) certifications.

Advantage	Explanation
High Strength and Pressure - Resistance	The seamless manufacturing process results in a uniform and dense structure, giving the tube excellent strength. It can withstand high internal pressures, making it ideal for high - pressure applications in power generation, petrochemical, and mechanical engineering.
Leak - Resistant	Without weld seams, the risk of leakage is significantly reduced. This is crucial in applications where the transported media are hazardous, expensive, or where maintaining system integrity is essential.
Good Fatigue Resistance	Generally, seamless tubes have better fatigue resistance compared to welded tubes. They can withstand repeated cyclic loading without developing cracks or failures as quickly, which is beneficial for applications with fluctuating pressures.
Superior Dimensional Accuracy	The rolling and finishing processes in seamless tube manufacturing can achieve high - level dimensional accuracy. This allows for easier installation and connection in complex piping systems, reducing the need for extensive on - site adjustments.

ASTM A213 T11/T12/T22 Tubes Seamless Ferritic and Austenitic Steel Boiler for Industry

Basic Info.