ASTM A53 (or ASME SA 53) and A106 are the two most popular steel types used in different industries. They are helpful for various purposes like transporting hot steam or fluids under high pressure. 

A53 and A106 share a few fundamental differences that you might overlook at first glance. However, these differences become crucial when sourcing for your business or operations. 

For example, A53 pipes come in three types, F, E, and S. They are also classified into two grades, Grade A and B. Each one again has different properties. 

Additionally, A106 pipes are also available in Grade A and B. However, only a single type of ASTM A106 pipe exists, unlike A53. 

In this blog, we will explore the differences between A53 and A106 pipes. We will go into details such as chemical composition, physical properties, tolerances of the pipes, and more. 

 A53 PipesA106 Pipes
DescriptionSpecifications for zinc-coated, welded, and seamless steel pipesSpecifications for standard carbon and seamless steel pipe
Common TypesF, E, S-
Common GradesA and BB
Common UsesLow-pressure water, gas, oil, and steamHigh-temperature and high-pressure applications in oil, power, and stressful industries
Yield Strength30,000 (Grade A)


35,000  (Grade B)

30,000 (Grade A)


35,000  (Grade B)

Tensile Strength48,000 (Grade A)


60,000 (Grade B)

48,000 (Grade A)


60,000 (Grade B)

Chemical CompositionChromium 0.4, Carbon 0.25 - 0.3, Manganese 0.95 - 1.2, Sulfur 0.45Chromium 0.4, Carbon 0.25 - 0.3, Manganese 0.27 - 1.06, Silicon 0.1
Wall thicknessThe nominal pipe’s size (minus) 12.5%The nominal pipe’s size (minus) 12.5%
Weight Per Foot+ / - 10%Between - 3.5% and 10% against specification
OD sizeNPS ⅛” - 1.½”NPS ¼” - 30”

Let’s start by looking at the difference between Grade A and Grade B pipes. 

Differences Between Grade A And Grade B Steel Pipes

Grade A and B steel pipes share a few differences in manufacturing and composition. Let’s explore them below:

Manufacturing Process

A53 Pipes

Type F Grade A steel pipes rely on a continuous coil for production. Additionally, the manufacturers seal the longitudinal joint using forge welding. However, you cannot buy Grade B pipes for type F A53 as there are no specifications.

All A53 pipes use raw steel produced in the following ways:

  • Basic oxygen furnace
  • Open hearth furnace
  • Electric furnace

Type E steel pipes, for instance, come in Grade A and B. They are produced using a continuous coil and rely on electrically-generated heat to seal the longitudinal joints. However, Grade B steel pipes undergo a heat treatment of at least 540 degrees C post welding. 

What about type S A53 steel pipes?

They are also available in Grade A and B. Manufacturers utilize the extrusion method to produce both grades of the pipes. 

A106 Pipes

A106 Grade B is the most common grade used in industries. Manufacturers melt raw steel using a furnace, just like A53 pipes. Additionally, they may also make use of refining or degassing. 

Additionally, producers use steel casts or strand casts. They also use heat treatment after the pipe is hot-finished. 

However, they treat cold-drawn pipes after they finish the cold draw pass. They are made only with a seamless execution method.

Cold Drawn pipes

Chemical Differences

A53 Grade A and B pipes share almost the same chemical composition except for a few metals. The same applies to A106 Grade A and B pipes. 

Below is a chart comparing both grades for A53 pipes:

TypeS & ES & EF

What about the composition of A106 Grade A and B pipes?

Manganese0.27 - 0.930.29 - 1.06

Benefits of Galvanized ASTM A53 and A106 Pipes 

Many industries use galvanized A53 and A106 pipes. What is a galvanized steel pipe?

Galvanized pipes go through a process called hot-dip galvanization. Manufacturers use the process to apply a protective layer of zinc both on the outer and inner sides of the pipe.

Generally, producers use a zinc coating of 1.6 to 1.8 oz per square foot. What are the benefits of galvanized A53 and A106 pipes?

Protection from Corrosion

Galvanization offers steel pipes protection from rust and corrosion. You can use them for different hazardous environments and fluids that cause corrosion.

As a result, your pipes last for a longer pipe compared to metals like iron or standard steel. 

High Durability

Steel is a durable material. Additionally, the protective layer of zinc provided during galvanization makes it more sturdy.

Therefore, you don’t have to worry about anything, even in stressful working conditions. 


Galvanized pipes are more affordable than copper pipes. They offer the same level of performance and durability but for a lower price. 

As a result, you can expect more returns from your investment. 

Pipe Tolerance: A53 vs. A106

The manufacturing tolerances for A53 pipes are as follows:

  • The thickness of the wall: At least the minimum size of the pipe (minus) 12.5%
  • Weight per foot: + / - 10%

Now, let’s check out the tolerance for A106 pipes:

  • The thickness of the wall: The nominal pipe’s size (minus) 12.5%
  • Weight per foot: Between - 3.5% and 10% against specification
  • Diameter: NPS 1/4″- 30″

A53 vs. A106: Chemical Composition

The chemical composition of A53 and A106 pipes are mostly similar. However, there are a few differences, like the presence of silicon in A106 pipes and its absence in A53 pipes.

Additionally, they also contain different amounts of the following components:


  • A53 - 0.95 - 1.2
  • A106 - 0.27 - 1.06


  • A53 - 0.05
  • A106 - 0.035


  • A53 - 0.45
  • A106 - 0.035

A53 vs. A106: Mechanical And Physical Properties

We will now explore the mechanical and physical properties of A53 and A106 pipes. 

Mechanical Properties Of A53 Pipes

The tensile strength of A53 pipes should be a minimum of 48,000 psi for Grade A. 

The minimum tensile strength for A53 Grade B pipes is 60,000 psi. 

Moreover, the yield strength of A53 Grade A pipes is 30,000. The same is 35,000 for A53 Grade B pipes. 

Physical Properties Of A53 Pipes

You can find the physical properties of A53 pipes below to make an informed purchase:

  • Density at 20-degrees C Kg/dm3 - 7,85
  • Modulus of elasticity kN/mm2 at:
  • 20-degrees C - 210
  • 300-degrees C - 192
  • 400-degrees C - 184
  • 450-degrees C - 179
  • Thermal conductivity at 20 degrees C W/m K - 51
  • Specific thermal capacity at 20 degrees C J/kg K - 461
  • Specific electrical resistivity at 20 degrees C - 0,20

Next, we will look at the properties of A106 pipes. 

Mechanical Properties of A106 Pipes

The tensile strength for A106 pipes is a minimum of 60,000 psi, while the yield strength for this type of pipe is 35,000 psi. 

Physical Properties of A106 Pipes

What are the physical properties of the A106 steel pipe?

The wall thickness for A106 pipes is between 50 mm to 7.00 mm. Additionally, the pipe size ranges between ½-inches and 36-inches for a nominal bore. 

How To Test Each Type Of Pipe And Grade

You may order a batch of A53 and A106 pipes by contacting a supplier. However, how do you make sure of the quality?

There are standard testing requirements for evaluating different steel pipes. We will discuss the testing requirements of both pipes so that you don’t have to compromise. 

Testing Requirements for A53 Steel Pipes

Perform the following tests on your A53 pipes before you pay the invoice:

  • Elongation testing - Established by formula
  • Tensile testing:
  • Grade A - 48,000 psi
  • Grade B - 60,000 psi
  • Yield testing:
  • Grade A - 30,000 psi
  • Grade B - 35,000 psi
  • Hydrostatic testing - transverse weld tension (= / > 8.625” OD)
  • Flattening testing - Bend test (- / = 2.375” OD)

Testing Requirements For A106 Steel Pipes

Here are the testing requirements for assessing the quality of A106 pipes:

  • Flattening Testing:
  • For nominal pipe size 2 to 5: < / = 400 
  • For nominal pipe size 6 and more: < / = 200
  • Tensile Testing:
  • For nominal pipe size 5 and less: < / = 400
  • For nominal pipe size 6 and more: < / = 200
  • Bending Testing:
  • For nominal pipe size 2 and less: < / = 400

Final Thoughts

A53 and A106 are different in composition and properties. They are also used for different purposes in a range of industries. Purchase your steel pipes based on the right information to ensure your investment brings expected results.