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X Ray Testing of Welds: 3 Important Considerations

The X ray testing of welds has become critical in the manufacturing industry especially in the quality assurance of assembled metal components.

Many welded metal components must comply with applicable Australian or international standards before they are put into service. This is particularly true for pressure vessels, pipelines, structural components, lifting equipment etc. These items are tested via non-destructive methods to ensure they meet these technical specifications. This is to prevent costly and catastrophic consequences. It also helps optimise processes to save on time and costs.

For different industries and specific applications, different methods are employed for quality testing of welds. One such non-destructive examination method is the x ray testing of welds. However, before using this method, it is recommended to take note of the following considerations:

1. Are the results accurate and reproducible?

Accuracy and precision are important in any testing methodology. Accuracy refers to the nearness of the test results to the true value. On the other hand, precision is about the reproducibility of the results. To assist with this, it is important that instruments used in the testing process are regularly calibrated to a known standard.

2. Do you require a combination of NDT methods?

For assembled metal components including those in pipes, joints and bends, companies employ a few methods (not just one) in testing welds. This is to ensure the consistency of results and comprehensiveness of the inspection.

Petroleum, automotive, aerospace and other vital industries perform testing on metal components and structures before putting them into service. Aside from x ray testing, they might also perform ultrasonic inspection, dye penetrant testing and magnetic particle inspection. Each of these methods has their own weaknesses and strengths.

3. What are the strengths and weaknesses of the inspection methods?

Different types of defects that may exist in any given sample could require different inspection methods to discover. For example, de-laminations and planar cracks can be difficult to detect using x ray testing or other radiographic methods. Ultrasonic and acoustic-based methods are more recommended for detecting these types of defects.

The size of the surface area to test may also dictate the testing methodology that is used. Dye penetrant testing for example, may be preferred for the rapid inspection of large surface areas at a relatively low cost. The down-sides of this method include the requirement for thorough surface preparation and chemical handling precautions.

X ray testing of welds Australia

Each non-destructive testing method has drawbacks and advantages. The key is selecting the appropriate NDT method to suit your requirements, and to ensure that the testing instruments used are properly maintained and calibrated.

At NDT Equipment Sales, we assist a wide variety of companies in different industries with their non-destructive testing needs. Contact us today and our experienced staff will be happy to help.