Rexarc is currently open from 7:30 AM – 4:00 PM EST, Monday – Friday. Read More


Why Use Stainless Steel for Pressure Vessels?

Choosing the right material for your pressure vessel is one of the most critical design choices to make. Stainless steel is one of the most popular choices, but do you know why it’s a great material to build a pressure vessel with, and what types of steel are best?

What is stainless steel?

Stainless steel refers to an iron and carbon alloy containing between 10 – 30% chromium, although it can also have small amounts of other elements like nickel, titanium, molybdenum, aluminum, and more. The elements making up the steel modify its properties, like its strength, ductility, resistance to corrosion, and melting temperature.

Types of stainless steel

The type of stainless steel is defined by the type and amount of elements making up the alloy. There’s more than 100 different grades of stainless steel, organized into categories including the following:

  • Ferritic
  • Austenitic
  • Martensitic

Ferritic stainless steel

This type of stainless steel often has a higher chromium content than the others, is very resistant to pitting, and has a higher thermal conductivity than austenitic stainless steel. It’s also magnetic, which not all stainless steels are.

Austenitic stainless steel

Austenitic stainless steel gets its name from the crystalline structure it forms, austenite (a face-centered cubic iron alloy). It’s non-magnetic, and often contains nickel, manganese, and nitrogen in addition to the usual chromium content.

Martensitic stainless steel

Martensite is a type of steel crystalline structure formed by rapidly cooling an iron and carbon alloy. It’s harder than austenitic and ferritic stainless steels.

Stainless steel types for pressure vessels

300 series stainless steels are the most commonly used stainless steels in pressure vessel manufacturing. They’re a set of austenitic nickel-chromium steels with a few key differences. The most common types of 300 series steels used for pressure vessels are described below:

  • 304: 18% Chromium, 8% Nickel
  • 316: Similar to 304, but with the addition of molybdenum for higher corrosion resistance
  • 317: Similar to 316, but with the addition of more nickel for even higher corrosion resistance

Why stainless steel is a good material for pressure vessels

There are a lot of reasons why you might choose to use a stainless steel type for your pressure vessel. Stainless steel is a readily available material, easy to machine, and there are many types to choose from for your specific project needs. It’s also a comparatively cheap material to purchase and manufacture, although the addition of nickel does raise the price.

Learn more

Rexarc is an expert in stainless steel pressure vessel design and manufacturing. We’d be happy to answer your questions about the right material for your project, or what the differences between stainless steels are. Feel free to reach out!



We are a one stop shop from custom vessel production to full skidding, plumbing and instrumentation.



We stand by our processes and communicate with you on your project status as much or as little as you would like.



We continually reinvest in our people, business, and equipment technology to ship quality products on time.