ASME Section IX 

Our August, September and October articles will address one of the core facets of our business, a facet that has been included in almost every communique with a potential client:

All weld procedures and welders are certified per ASME B31.1 and B31.3, in accordance with ASME Section IX.

That simple statement has a profound importance in the product that Dixie provides our customers. This month, we will investigate the history of ASME Section IX and the reasons behind its development.

The history of ASME Section IX is closely tied to the growth of the American pressure vessel and power industries. As boilers, steam systems, and later power plants became larger and operated at higher temperatures and pressures, it became clear that weld quality could no longer depend solely on the experience of individual welders. A standardized system was needed to ensure consistent, safe, and repeatable welding practices.

The Early Years (1880s–1915)

During the late 19th and early 20th centuries, the United States experienced rapid industrialization. Steam boilers powered factories, railroads, ships, and electric generating stations. Unfortunately, boiler explosions were common due to poor design, inferior materials, and inconsistent fabrication methods.

Thousands of people were killed or injured in boiler explosions during this period. One of the most significant incidents occurred in 1905 at the Grover Shoe Factory in Brockton, Massachusetts, where a boiler explosion killed 58 people and injured more than 100. Tragedies like this created strong public demand for uniform engineering standards.

Birth of ASME Boiler Code (1915)

The American Society of Mechanical Engineers responded by publishing the first ASME Boiler Code in 1915. This code focused primarily on:

• Boiler design
• Material selection
• Construction methods
• Inspection requirements

At that time, most pressure-retaining components were riveted, not welded.

Welding Changes Everything (1920s–1930s)

As welding technology advanced during the 1920s and 1930s, engineers recognized several advantages over riveting:

• Stronger joints
• Reduced weight
• Lower manufacturing costs
• Faster fabrication
• Improved pressure integrity

However, welding quality varied significantly between fabricators because there were no universal qualification requirements.

Need for Standardized Welding Qualifications

By the 1930s and 1940s, industries using pressure equipment wanted assurance that:

Welding procedures had been proven effective.

• Welders possessed adequate skills.
• Welding variables were controlled.
• Fabrication quality was consistent regardless of contractor.

These needs ultimately led to the development of a dedicated welding qualification code.

Creation of ASME Section IX

ASME officially introduced Section IX (Welding Qualifications) with the 1937 edition of the ASME Boiler and Pressure Vessel Code. Section IX was first issued as part of the ASME BPVC, originally published as a supplement to Section VIII (Pressure Vessels).

In 1941, Section IX became a stand-alone section of the Boiler and Pressure Vessel Code, recognizing the growing importance of welding qualification across all ASME construction codes.

These standardized qualification requirements included:

• Welding procedures
• Welders
• Welding operators

Rather than specifying how every weld must be made, Section IX requires fabricators to demonstrate through testing that their procedures produce sound welds and that their personnel can perform them consistently.

Currently, Section IX is the ASME Standard for Welder Performance and Welding Procedure Qualification. Over the years, Section IX has been expanded to include different welding technologies and new base materials, which we will touch upon at a later date.