This method, together with Ultrasound Testing (UT), increases the reliability of tests on metals, metal sheeting, masts and steel rigging parts examined to reveal cracks and possible breakage points.
A crack is the condition which precedes total structural failure. In fact, it is triggered at loads lower
than those required for complete breakage.
Surface cracks that do not extend internally within the workpiece can escape both visual inspection and UT, which primarily evaluates the interior of the material and therefore, in various cases, Penetrating Liquids (PT) need to be employed.
An example of where Penetrating Liquids are required (as a complement to UT examination), is during inspection of rigging Tips or threaded pins.
Perfect cleanliness of the samples is a prerequisite for performing this test.
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