Visual Testing (VT) is a method of examining for surface flaws on a piece of material or equipment by assessing it visually. It is the oldest form of testing and remains one of the most reliable to this day. No examination is more valuable than the one performed using the eyes of an experienced inspector. In fact, many other NDE methods simply provide an enhanced or volumetric view for the eyes of the inspector to analyze.
Direct visual examination is the key to ensuring welding operations are performed in accordance with the governing codes and procedures. Visual examination is performed during in-service examinations of piping, vessels, tanks, boilers, and other equipment to detect a wide range of conditions and may be supplemented by mechanical measurements, photography, magnification, or chemical etching or response methods.
Aside from its reliability, it has several advantages compared to other testing methods. It doesn’t require any complicated equipment, and is therefore much less expensive to perform than other testing methods that do require expensive equipment. Likewise, it’s also much less difficult to perform than other methods.
While VT is among most reliable NDE methods, that doesn’t mean it’s without its limitations. Many flaws might not be visible to the naked eye yet still be dangerous. Likewise, VT can only detect flaws in areas that can been seen, so those that are in areas that are difficult or impossible to examine visually, such as subsurface flaws, may go undetected in a visual examination. Hi-Tech Testing has the expertise and capabilities to perform a multitude of other conventional and advanced NDE/NDT methods to account for this.
Many inaccessible areas can be visibly examined using one of several remote viewing devices available to our personnel such as videoprobes, zoom cameras, or camera crawlers. Hi-Tech Testing has personnel certified in visual examination via AWS CWI, AWS SCWI, API Inspector and ASNT Level III VT.