Common Stainless Steel Welded Pipe Standards

In the various engineering projects I've encountered, stainless steel welded pipes are almost ubiquitous—from petrochemical pipelines and building structures to machinery manufacturing and energy projects. While seemingly ordinary, every single pipe is crucial to safety and stability, so material selection and standards cannot be taken lightly.I've compiled several commonly used standards and some of my project experience, hoping it will be helpful.

In the various engineering projects I've encountered, stainless steel welded pipes are almost ubiquitous—from petrochemical pipelines and building structures to machinery manufacturing and energy projects. While seemingly ordinary, every single pipe is crucial to safety and stability, so material selection and standards cannot be taken lightly.

I've compiled several commonly used standards and some of my project experience, hoping it will be helpful.

ASTM Standards

Internationally, ASTM is considered the most widely used standard. Different standards are applicable to different scenarios:

A249: Pipes used in high-temperature, high-pressure boilers and heat exchangers. I used this type of pipe for reactor piping in an oil refinery project; its high-temperature resistance was very stable.

A269: General fluid pipelines, such as those used for cooling water or chemical liquid transportation in factories.

A312: Both seamless and welded pipes are available; very common in petrochemical and natural gas pipelines.

A358: Large-diameter, thick-walled pipes, mostly used in pressure vessels and supporting structures.

A554: Square and rectangular tubing, commonly used in stair railings, furniture, and decorative projects, offering both aesthetics and sturdiness. I worked on a hotel stair railing project that used this type of tubing.

Tips: When selecting tubing, always consider corrosion resistance and mechanical properties, not just the model number.

Japan JIS G3446

This standard is common in the construction and automotive industries, frequently used in bridge structures and automotive exhaust pipes. I worked on a bridge renovation project using G3446 tubing, which, with anti-corrosion treatment, showed no rust even in humid and hot environments.

China GB/T 12770

This type of tubing is commonly used in domestic urban pipe networks and water supply systems, offering excellent pressure resistance and sealing performance. The food industry also uses this type of tubing for intravenous infusions. I saw in a municipal project that, with proper joint treatment, this type of tubing hadn't leaked for over a decade.

Europe EN 10305

Primarily used for high-precision applications, such as medical devices and laboratory equipment. Small diameter, smooth surface, and strict dimensional requirements. In medical device factories, this type of tubing is used for internal tubing of surgical instruments, with virtually zero error.

ASME SA249 (American Society of Mechanical Engineers)

Preferred for high-temperature and high-pressure environments, widely used in petrochemical plants, heat exchangers, and pressure vessels. I have worked on reactor bypass piping in an oil refinery, and before welding, I carefully checked the material and thickness of SA249, ensuring a high safety margin.

Summary of Experience

Selecting tubing should begin with the intended use: high temperature, high pressure, general fluid delivery, structural support—each environment is different.

Corrosive environments are critical: coastal areas and chemical corrosive environments require tubing with high corrosion resistance.

Surface treatment and welding methods: For medical or decorative applications, a smooth surface is crucial; welding must meet process requirements.

Experience Sharing: Try to select tubing based on actual project cases. Even with excellent theoretical data, problems can easily arise without field experience.