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What is a coded Welder, Multi Coded Welder or Just Coded Welding?

As a coded welder, you will possess the skills required to work in some of the most highly regulated sectors and on a range of safety-critical applications such as pressure vessels and pressure pipework.

So What is a Coded Welder?

A coded welder is a terminology used for an approved welder against a particular standard. The qualification or standard you are approved for will not mention the term coded welder.

The name coded welder is a technical term to describes a time served and skilled welders. Who will have completed a welder approval testing to a specification or standard such as ASME IX.

For the UK approvals are conducted to BS EN ISO standards and for the  USA the ASME IX and AWS standard.


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Why have Coded Welders?

Applying standards of practice ensure that a welded joint has an acceptable level of quality and integrity required for the job. As a coded welder in the UK you will be working to one of the following:

  • National British Standard (BS)
  • European British Standard European Standard (BS EN)
  • US American Welding Society (AWS) and American Society of Mechanical Engineers (ASME)
  • International Standards Organisation (ISO)

Standards for specific industries and job roles:

Class 1 Welder Coding –  BS EN ISO 9606ASME Section IX

Welder approval testing is carried out by a competent welder observed by a welding inspector. An assessment of the weld quality using non-destructive (X-ray, UT) and mechanical (Bend Tests) testing techniques takes place in a UCAS approved laboratory. Once both elements pass, the welder becomes approved.

Approval tests examine a welder’s skill and ability under pressure. Testing demonstrates that a welding procedures design is fit for purpose, producing a welded joint that will meet the mechanical and quality requirements for the job.

Usually, testing is job-specific. You will be tested to that specification to qualify thus becoming a coded welder.

 BS EN ISO 9606ASME Section IX are appropriate for welders working on pressure vessel, piping, off-shore structures and for other products where the consequences of failure are catastrophic such as structural steel.

Class 2 Welder Coding, BS 4872

In less demanding situations, such as small to medium building frames and non-structural work, an approved welding procedure may not be necessary. However, to ensure an adequate level of skill, welders are often recommended to a less stringent standard such as the BS 4872.

The  BS 4872 offers a measure of competence to people who are using welding for maintenance or as a small part of their job role.

Being a coded welder in a particular specification does not cover you for all standards. Each specification requires welder training, welding tests and examination. People who have passed multiple tests for different standards are called multi-coded welder.

Adapted from https://www.twi-global.com/technical-knowledge/job-knowledge/standards-application-standards-codes-of-practice-and-quality-levels-038 BS EN ISO 9606ASME Section IX

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