Weld testing is a greatly specialised discipline requiring skill and expertise, with testing methods being a central aspect of weld procedures for a multitude of construction and fabrication processes.
The Importance of Weld Testing
Errors in welding can cause significant damage to weld metals which may lead to loss of strength and durability and even costly structural failures.
Testing facilities provide assurance that products are fit for purpose through a variety of inspection methods, such as visual inspection and other testing services that assess weld quality.
Ensuring that specific standards are met allows for the smooth running of assets and the avoidance of errors and possible extra costs.
Weld Testing Methods
Weld Testing can broadly be broken down into two different types; non-destructive testing (NDT) and destructive testing.
Destructive testing measures the physical properties of base metals and components in order to better understand a material’s performance under certain conditions. Compared to non-destructive testing, destructive testing methods are generally easier to perform, while also providing more information and easier interpretation of results.
Destructive testing includes mechanical testing – such as tensile tests, bend tests and impact tests – hardness testing and material analysis. These testing methods are most fruitfully used when testing products that are not going to be mass-produced, as it goes against economic interests to destroy a large number of specimens.
Non-destructive weld testing involves the evaluation of the structural quality of components without causing damage to them. This type of testing has the benefit of saving time and money in product evaluation and research. Various types of engineering make use of NDT methods, such as forensic engineering, mechanical engineering, petroleum engineering and electrical engineering.
An example of a non-destructive testing method is magnetic particle inspection, also known as magnetic particle testing. This technique is used to identify potential flaws in ferromagnetic material surfaces, such as iron, nickel, cobalt and a few of their alloys. Some of the advantages of magnetic particle inspection compared to other non-destructive testing methods are that it is cheaper in comparison, very portable and does not require a rigorous cleaning process before use. However, this method is constrained in other aspects, such as the fact that the material used must be ferromagnetic, and the orientation and strength of the magnetic field is also significant.
Weld Testing at TWI
TWI can help you with all aspects of weld testing, including quality evaluation, process and parameter determination, safety reviews and alignment with quality codes and standards.