Weldtest NZ Limited

Visual Inspection Overview

This fortnight we are looking at Visual Inspections and providing a brief but interesting overview.

Visual inspections are one of the most common and oldest forms of non-destructive testing (NDT).
Although to be technically correct, a visual inspection is really an examination rather than a test. The difference being that a test requires equipment being utilised or incorporated into the examination. A test is also normally invasive.

Although visual inspection/examination remains a surface inspection only, it is still extremely effective and is widely used as a reliable form of quality control.

Compared to other inspection methods, visual examination is more cost effective. This is because there is little to no equipment required to perform the test and wider areas can be examined much quicker as a result. Visual inspections are simple and less technologically advanced compared to alternative testing methods.

This type of inspection also often eliminates the need for further types of testing but is normally the minimum required for pre-test methods such as magnetic particle inspection (MPI) or magnetic testing (MT) and or ultrasonic testing (UT). Visual inspections are widely used in the structural steel industry.

Visual inspection is typically the first step in the testing process and is used to inspect a variety of external and internal surfaces. These include but are not limited to storage tanks, pressure vessels, piping, castings, forgings, machined components and welded structures.

So there we have it for this fortnight. Please feel free to email us if you have any feedback or thoughts for upcoming articles.