Unlocking the Strength of Stainless Steel: A Guide to Stainless Steel Tube Standards

As professionals in the stainless steel tube industry, it is essential to understand the importance of stainless steel tube standards for successful and safe operations. Standards are designed to promote safety, reliability, and quality. Without them, manufacturers cannot ensure the consistency of their product.

 

They also help to reduce costs, as they eliminate the need to continually monitor and inspect products.

 

In addition, standards provide a common language for communication between buyers and sellers, helping to ensure that everyone is on the same page. Standards also help to ensure that materials are compliant with international regulations and standards. This helps to ensure that products are safe, reliable, and of high quality.

 

With the increasing demand for stainless steel tube products, understanding the standards that govern them is essential for businesses and consumers alike. These standards ensure the quality and safety of the products, allowing them to meet the needs of both the industry and the consumer.

stainless steel tube standards

Common standards explanation

When it comes to stainless steel tubes, there are a few common standards that are widely used in the industry. These include:

 

- ASTM A312

- ASTM A270 /EN10357 / DIN11850

- ASTM A554/EN10296-2

- ASTM A269/EN10217-7

- ASME SB677

 

All of these standards are popular for their extremely corrosive resistance.

ASTM A312 Stainless Steel Tube Standards

The ASTM A312 is a standard specification for seamless and heavily cold-worked austenitic stainless steel tubes

Stainless Steel Grade for ASTM A312 

Although ASTM A312 is one of the most commonly used stainless steel tube standards , there are many grades of stainless steel that are suitable for use in its production. The most common grade is 304, which offers excellent corrosion resistance, along with other grades such as 316 and 321. Each grade offers different levels of performance, so it is important to determine the right grade for the specific application.

 

Chemical Composition for ASTM A312

 

Grade

Carbon

Manganese

Phosphorus

Sulfur

Silicon

Chromium

Nickel

Molybdenum

304

0.08

2.00

0.045

0.03

1.00

18.0-20.0

8.0-11.0

 

304L

0.35

2.00

0.045

0.03

1.00

18.0-20.0

8.0-3.0

 

316

0.08

2.00

0.045

0.030

1.00

16.0-18.0

11.0-14.0

2.00-3.00

316L

0.35

2.00

0.045

0.030

1.00

16.0-18.0

10.0-14.0

2.00-3.00

 
 
Mechanical properties

 

Grade

Tensile Strength, min Ksi (Mpa)

Yied Strength ,min ksi (Mpa)

304

75  (515)

30  (205)

304L

70  (485)

25  (170)

316

75  (515)

30  (205)

316L

70  (485)

25  (170)

 

 

Permitted Tolerance in wall thickness in ASTM A312

 

Tolerance, %  from Nominal

NPS Designator

Over (+)

Under  (-)

1/8 to 2 1/2 Incl,  aal t/D ratios

20.0

12.S

3 to 18 incl., t/D up to 5% incl

22.5

12.5

20 and larger, welded all t/D ratios

17.5

12.5

20 and larger, seamless t/D up to  5% incl

22.5

12.5

20 and larger, seamless  t/D > 5%

15.0

12.5

 

Where:
t = Nominal Wall Thickness
D = Ordered Outside Diameter

Application of ASTM A312

ASTM A312 is suitable for a variety of applications, including chemical processing, food processing, pharmaceuticals, and heat exchangers. It is also widely used in the oil and gas industry due to its superior corrosion resistance and strength.

 

Additionally, ASTM A312 is known for its tight dimensional tolerances and ability to meet the most exacting standards. Its superior properties make it the ideal choice for many applications.

 ASTM A270/EN217-7 Stainless Steel Tube Standards

 

 

Stainless Steel Grade for ASTM A270

Most stainless steel tubes produced for use in ASTM A270 stainless steel tube standards are grade 304 or 316. Grade 304 is a low-carbon stainless steel alloy, while grade 316 is a higher-carbon alloy. Both grades are highly corrosion-resistant and have excellent mechanical properties. They are also cost effective and offer excellent weldability. The mechanical properties and chemical composition of 304 316 can be referred to above .

Permitted Tolerance in wall thickness in ASTM A270

Taking into account ASTM A270 stainless steel tube standards, permitted tolerance in wall thickness of stainless steel tubes must be considered. This tolerance is set at +/- 12.5% of the specified wall thickness, and it applies to all sizes of tubes.

The tolerance limit can be varied depending on the particular product, such as by using a tighter tolerance or by increasing the wall thickness.

The purpose of this tolerance is to ensure that the tube meets the specified requirements, and that any defects are minimized.

 

Manufacture processes of ASTM A270

Forming: The selected stainless steel billets or coils are formed into tubing through various methods, such as hot or cold working processes like extrusion, rolling, or welding. The forming process ensures the creation of tubes with the required dimensions and specifications.

 

 

Heat Treatment: In some cases, heat treatment may be employed to improve the mechanical properties of the stainless steel tubing, such as increasing its hardness or strength. Annealing, quenching, or tempering processes might be used based on the required properties.

 

 

Cold Drawing/Cold Rolling: This process involves reducing the diameter and wall thickness of the tubing through cold working, typically to achieve the desired dimensions and surface finish. Cold drawing or cold rolling helps in achieving tight tolerances and a smooth surface finish.

 

 

Finishing: Surface finish is crucial for sanitary tubing to meet the specifications outlined in ASTM A270 stainless steel tube standards . Finishing processes like polishing, grinding, or buffing are employed to achieve the required surface roughness and cleanliness, ensuring the tubing's suitability for sanitary applications.

ASTM A270

Application of ASTM A270

ASTM A270 stainless steel tube standards is commonly used in food, dairy, and beverage industries due to its sanitary requirements and corrosion resistance. It is also used in pharmaceutical and medical industries for its superior hygienic standards.

Stainless Steel Grade for ASTM A554

Stainless steel grade for ASTM A554/EN10296-2 is an important factor to consider when selecting a tube for specific applications. Depending on the grade, welded tubes are suitable for different temperatures and corrosive environments.

 

Generally, the higher the grade, the higher the strength of the tube, making it more resistant to corrosion. The grades that are available include 304, 316, 316L, 409, and 430.

 

Element (Percentage by Weight)

Grade 304

Grade 316

Grade 316L

Grade 409

Grade 430

Carbon (C)

≤ 0.08

≤ 0.08

≤ 0.035

≤ 0.08

≤ 0.12

Manganese (Mn)

≤ 2.00

≤ 2.00

≤ 2.00

≤ 1.00

≤ 1.00

Phosphorus (P)

≤ 0.045

≤ 0.045

≤ 0.045

≤ 0.045

≤ 0.040

Sulfur (S)

≤ 0.030

≤ 0.030

≤ 0.030

≤ 0.040

≤ 0.030

Silicon (Si)

≤ 1.00

≤ 1.00

≤ 1.00

≤ 1.00

≤ 1.00

Chromium (Cr)

18.0-20.0

16.0-18.0

16.0-18.0

10.5-11.7

16.0-18.0

Nickel (Ni)

8.0-10.5

10.0-14.0

10.0-14.0

-

-

Molybdenum (Mo)

-

2.0-3.0

2.0-3.0

-

-

Nitrogen (N)

-

-

-

-

-

Copper (Cu)

-

-

-

-

-

rectangular tube satin finish

Mechanical Properties

 

Stainless Steel Grade

Tensile Strength (MPa)

Yield Strength (MPa)

Elongation (%)

Hardness (HRB/HB)

304

515 (min)

205 (min)

40 (min)

92 (max)

316

515 (min)

205 (min)

40 (min)

95 (max)

316L

485 (min)

170 (min)

40 (min)

95 (max)

409

380 (min)

205 (min)

20 (min)

88 (max)

430

450 (min)

205 (min)

22 (min)

183 (max)

Outside diameter tolerance and wall thickness tolerance of ASTM A554 

 

Property

Tolerance

Outside Diameter (OD)

±0.005 inches (0.13 mm) to ±0.015 inches (0.38 mm), depending on size and wall thickness

Wall Thickness

±10% to ±12.5% of the nominal wall thickness, depending on specified size and wall thickness

Manufacture processes of ASTM A554

Tube Formation:

Welded Tube: Stainless steel strips or coils are formed into a tubular shape through various methods like rotary bending, roll bending, or continuous bending processes.

Welding: The formed tube edges are welded together using various techniques such as TIG (Tungsten Inert Gas) welding, laser welding, or high-frequency induction welding, ensuring strong and consistent bonding.

 

Surface Treatment:

Polishing/Finishing: The tubing surface might undergo processes like polishing, grinding, or buffing to achieve the desired surface finish (e.g., brushed, satin, mirror finish) specified in ASTM A554.

 

Application of ASTM A554

ASTM A554 stainless steel tube standards is used in various industries like architecture, automotive, and construction due to its resistance to rust, strength, and good looks. It's commonly seen in handrails, automotive exhausts, and building structures because it doesn't corrode easily and is strong. Basically, it's a durable, good-looking steel tubing used in many things we see and use every day!

rectangular tube satin fiish application

Stainless Steel Grade for ASTM A269

In regards to ASTM A269/ EN10217-7, the stainless steel grade used is of vital importance. It is essential to select the right grade to ensure optimal corrosion resistance, mechanical properties, and weldability.

 

304 and 316 are the two most common grades, with 304 being the standard grade and 316 containing higher levels of molybdenum, giving it superior resistance to pitting and corrosion.

 

Other grades such as 321 and 347 are also available, but their uses are usually limited or specialized.

 

 

Building on the importance of the mechanical properties of stainless steel grade, the permitted tolerance in wall thickness of ASTM A269/ EN10217-7 is a critical factor to consider.

 

This standard specifies the requirements for seamless and welded austenitic steel tubes intended for general corrosion-resisting and low- or high-temperature service.

 

It includes the permissible variations in wall thickness, outside diameter, and average wall of tubes.

 

It also includes the minimum number of tests, and the type of test to be performed for quality control.

 

Application of ASTM A269

 

ASTM A269 stainless steel tube standards is widely used in industries such as chemical processing, automotive, and medical equipment due to its corrosion resistance and durability. It finds applications in heat exchangers, pipelines, and food processing equipment, meeting stringent standards for cleanliness and reliability. Its versatility makes it a preferred choice for structures, equipment, and systems requiring resilience against corrosion in harsh environments.

Moving on, the next topic to be discussed is ASME SB677, which provides extremely corrosive resistance.

 

ASME SB677 – Extremely corrosive resistance

The ASME SB677 standard provides exceptional corrosion resistance for stainless steel tubes in highly corrosive environments. It offers superior resistance to pitting and crevice corrosion, along with extreme resistance to stress corrosion cracking. This standard is widely used in chemical plants, food processing, and other industries where high levels of corrosive agents are present.

 

The use of this standard ensures that stainless steel tubes are able to withstand the harshest of conditions and maintain their structural integrity. ASME SB677 is a great choice for applications that require maximum corrosion resistance and reliability.

ASTM A790 – Good resistance on stress corrosion cracking

Adhering to the common standard of ASTM A790 provides good resistance to stress corrosion cracking. It is a standard mainly used in the production of stainless steel pipes for various industries. This standard sets requirements for steel composition, chemical analysis, mechanical properties, and testing.

 

The steel must be an austenitic stainless steel with excellent corrosion resistance and a minimum chromium content of 18%. It also requires a maximum carbon content of 0.03%. In addition, the ASTM A790 standard requires a minimum tensile strength of 620 MPa, and a minimum elongation of 25%.

 

The good resistance on stress corrosion cracking makes it a reliable choice for applications that require extreme corrosion resistance. This marks the conclusion of the explanation of ASTM A790 and its good resistance on stress corrosion cracking.

 

Conclusion

In conclusion, comprehensive understanding of stainless steel tube standards is essential for successful application. With this knowledge, it is possible to identify the right type of steel for the intended purpose, ensuring that the project is completed to the highest quality.

The most commonly used stainless steel standards are ASTM A312, A790, and A269. Each of these standards has its own advantages and disadvantages, depending on the project requirements.

The ASTM A312 standard is most suitable for seamless stainless steel pipes and tubingBoth of these standards offer good resistance to stress corrosion cracking.

On the other hand, the ASTM A269 standard is suitable for heat exchanger and condenser tubing applications. This standard is more resistant to corrosion and provides good strength at high temperatures.

In conclusion, stainless steel tubes are an important material for a variety of applications.

The various standards for stainless steel tubes are essential in ensuring the quality and consistency of these materials.

Understanding the common standards can help ensure the proper selection and use of stainless steel tubes for the desired application.

 

 

Vinmay Stainless Steel ------Your Best Partner of Stainless Steel Tube Business

Foshan Vinmay Stainless Steel Co.,ltd is a large-scale international enterprise which concentrates on manufacturuing and selling of stainless steel welded tubes and the related fittings.

Our products are strictly produced according to a various of international standards including stainless steel welded tubes for ornamental and mechanical structure purposes (ASTM  A554/EN10296-2) ; Stainless steel welded tubes for boiler, heat exchanger and condenser ( ASTM A249/EN 10217-7) ; Stainless steel sanitary welded tubes ( ASTM A270/ EN 10357 / DIN 11850) and light gauge stainless steel water tubes  ( EN 10312).

If you are planing to purchase stainless steel tube recently , please feel free to contact us today!

 

 

 

 

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