According to certain philosophers, the best answer is always the simplest answer. While simplicity isn’t always the nature of nondestructive testing, “simple” is one way to describe visual testing: a method of nondestructive testing.
“Simple” does not imply that visual testing is easy; it is just as important to follow the guidelines of visual testing as it is for any other method. Visual testing is regarded as a simple method because it typically does not involve complicated instruments and equipment like liquid penetrant testing or magnetic particle testing.
When visual testing, the equipment necessary to conduct the inspection can be as simple as the naked eye. In some circumstances, where safety or height are of particular concern, some technicians may opt to use a drone to capture images that would be difficult, impossible, or dangerous to obtain if attempted by a technician.
The simplicity of performing visual testing, and the little to no equipment required, are primary reasons many technicians may opt for this method, but there are a number of circumstances in which visual testing is the right choice over other, more complicated methods.
Visual testing is a very cost-effective method, often costing clients much less than other methods of nondestructive testing. Especially when cost is a factor, visual testing will be the right choice.
It goes without saying that testing methods are only as effective as the technicians performing them. Visual testing is a method that is fairly easy to train for newer technicians, so it may be the perfect method when the technicians for the job are newer and there are no Level III NDT Certified technicians available.
Visual testing also requires little preparation, so when there is no time to clean the asset, visual testing may also be the best method.
While visual testing can be a simple, cost-effective method for inspecting an asset, it does have a number of limitations that make it an inappropriate method for some circumstances.
Visual testing is only effective for identifying surface indications, so it will not be able to detect a flaw that may be below the asset’s surface. It is also only effective for flaws that are large -- these must be large enough to be detected by the unaided eye or a drone’s camera. This means that any flaw below the surface of an asset, like those within a weld, would not be detectable through visual testing.
Visual testing is a method that can also be misinterpreted easily, so it is important that it is not used in circumstances where misidentification can cause damage or injury. Things like utility and light poles are at a constant risk of falling, and failure to identify a flaw in these circumstances could prove deadly.
In general, visual testing should only be reserved for flaws that are large and near the surface.
To the untrained eye, a quick visual test could easily lead a technician to believe that there is no flaw present. It takes a skilled professional to properly interpret a visual test and recognize whether or not that one test is enough.
If you are looking for nondestructive testing services to protect your assets or to become a technician yourself through NDT technician training, it’s crucial to choose the right NDT training institute to meet your NDT needs.
TXNDT is a cut above the rest with superior NDT courses, knowledgeable instructors, and hands-on coursework to prepare all emerging technicians for NDT certification. Check us out online or give us a call today at 281-231-0001 to see how TXNDT can work for you!