A guide to stainless steel and nickel alloy tube standards

Stainless steel and nickel alloy tubes are selected when ordinary carbon steel cannot provide the required combination of corrosion resistance, temperature performance, strength, or service durability.

The supplied TÜV Rheinland material list includes a wide range of ASTM, ASME, UNS and nickel alloy designations, covering stainless steel, duplex stainless steel, nickel-copper alloys, nickel-chromium-molybdenum alloys, and other corrosion-resistant materials.

Rather than treating these grades as one broad "stainless steel" category, buyers should understand the differences between the material families and the standards used to specify them.

Stainless and Nickel Alloy Materials in the List

The supplied table includes the following major material groups:

Important: The table above follows the supplied material list. The source image is a TÜV Rheinland approved material list; it should not be interpreted as stating that every listed grade is itself a certification or approval held by Union Steel Industry.

Stainless Steel Tubes: ASTM A213 and A312

Two of the most prominent stainless steel specifications in the table are ASTM A213 and ASTM A312.

The listed dimensional range for both is:

Outside Diameter: Ø25–101.6 mm

Wall Thickness: 1–15 mm

The source lists grades and alloys including:

TP304

TP304L

TP304H

TP316

TP316L

TP316H

TP321

TP310S

TP310H

TP347

TP347H

N08800

N08810

N08811

N08020

N08028

The presence of both conventional stainless grades and higher-alloy materials in the list demonstrates the range of materials available for thermal and corrosion-resistant tube applications.

ASTM A213 Stainless and Alloy Tubes

The A213 section of the source includes both conventional stainless grades and high-temperature alloy materials.

Examples include:

TP304 / TP304L
TP316 / TP316L
TP321
TP310S / TP310H
TP347 / TP347H

It also lists nickel-iron-chromium alloy designations such as:

N08800, N08810 and N08811

This combination makes the A213 material family particularly relevant when tube selection involves thermal equipment and demanding service conditions.

ASTM A312 Stainless Steel Pipe

The supplied list also identifies ASTM A312 grades including:

TP304

TP304L

TP304H

TP316

TP316L

TP316H

TP321

TP347

TP347H

along with:

N08800

N08810

N08811

N08020

N08028

The table gives the same Ø25–101.6 mm / 1–15 mm dimensional range.

For procurement, the important point is to identify not only "stainless steel" but the specific grade and standard required by the project.

Duplex Stainless Steel: ASTM A789 and A790

The approved material list also contains duplex and stainless grades under ASTM A789 and A790.

The listed designations are:

S31500

S31803

S32205

S32750

S32304

Both standards are shown with:

Ø25–101.6 mm

Wall Thickness: 1–15 mm

These materials are relevant when a project requires a combination of stainless corrosion resistance and higher-strength duplex material characteristics.

For buyers, the grade designation is critical. "Duplex stainless steel" alone is not sufficient for a technical RFQ because different duplex grades have different compositions and performance requirements.

Nickel Alloy Tubes: ASME SB / ASTM B Standards

The second major material family in the source is the ASME SB / ASTM B series.

Unlike conventional carbon steel or stainless steel specifications, these materials include numerous nickel alloy designations identified by UNS numbers.

ASTM B161 / ASME SB-161

The source lists:

N02200

N02201

with Ø25–101.6 mm diameter and 1–15 mm wall thickness.

ASTM B163 / ASME SB-163

Listed materials include:

N06600

N06601

N08825

N08800

N08810

N08811

ASTM B165 / ASME SB-165

The listed grade is:

N04400

ASTM B167 / ASME SB-167

The source lists:

N06600

N06601

N06690

These grades demonstrate the broad range of nickel-based materials covered by the approved material list.

High-Alloy Materials in the B Series

The table also contains several specifications associated with higher-alloy corrosion- and heat-resistant materials.

ASTM B407

Listed grades:

N08800

N08810

N08811

ASTM B423

Listed grade:

N08825

ASTM B444

Listed grade:

N06625

ASTM B622

Listed grades:

N10276

N06885

ASTM B677

Listed grades:

N08925

N08926

ASTM B729

Listed grade:

N08020

All of these entries are shown in the supplied table with the same reference dimensional range of Ø25–101.6 mm and 1–15 mm wall thickness.

Why Nickel Alloys Are Considered for Demanding Service

Nickel alloy tubes are generally considered when material selection requires performance beyond conventional carbon steel or standard stainless grades.

Depending on the specific alloy, project requirements may involve factors such as:

Corrosion resistance

High-temperature service

Resistance to aggressive process environments

Strength at elevated temperature

Long-term material stability

However, these properties vary significantly between individual alloys.

Therefore, a buyer should never specify only "nickel alloy tube" without identifying the required ASTM/ASME specification and UNS designation.

Stainless Steel vs. Duplex vs. Nickel Alloy

The material families in the source can be viewed at a high level as follows:

This is a material-selection framework rather than a ranking. The appropriate grade depends on the actual operating environment.

How to Specify Stainless or Nickel Alloy Tubes

A complete inquiry should include:

Material standard

For example:

ASTM A213

ASTM A312

ASTM A789

ASTM A790

ASTM B161

ASTM B163

ASTM B165

ASTM B167

ASTM B407

ASTM B423

ASTM B444

ASTM B622

ASTM B677

ASTM B729

Grade / UNS designation

Examples include TP316L, S32750, N06625, N10276 and N08825.

Dimensions

The supplied list generally shows:

Ø25–101.6 mm

Thickness 1–15 mm

Project requirements

Also confirm applicable heat treatment, testing, inspection, certification, surface condition, length and other project-specific requirements.

FAQ

1. What stainless grades are listed?

The table includes TP304, TP304L, TP304H, TP316, TP316L, TP316H, TP321, TP310S, TP310H, TP347 and TP347H.

2. Which duplex grades are listed?

S31500, S31803, S32205, S32750 and S32304 are listed under A789/A790.

3. Which nickel alloys are included?

The table includes UNS designations such as N06625, N10276, N08825, N06600, N04400 and others.

4. What dimensions are listed?

Most stainless and nickel alloy entries are shown as Ø25–101.6 mm with 1–15 mm wall thickness.