Importance of nondestructive testing emphasised

9th September 2016 By: Kimberley Smuts - Creamer Media Reporter

Importance of  nondestructive  testing emphasised

CERTIFICATION REMAINS CRUCIAL All pressure equipment has to be inspected by a competent person every three years

Regular testing and certification of equipment used in the engineering industry remains important to ensure that degradation of equipment is minimal, comments inspection and testing solutions provider Non-destructive Testing and Inspection Solutions (NIS).

NIS spokesperson Jannie de Beer details that equipment starts to degrade once it is exposed to the atmosphere. He adds that, in some areas, the atmosphere is more corrosive and the equipment could degrade quicker than predicted during the design.

This might manifest in instances where a pressure vessel being used in Johannesburg might not require as much external protection (coating) as the same vessel would when used in coastal towns.

“Contaminants in the product may also affect the corrosiveness of the inside surfaces of equipment . . . degradation might develop in different areas inside two seemingly identical pieces of equipment and is not visible from the outside,” De Beer adds.

He highlights that by inspecting equipment regularly and knowing where to expect degradation will allow for determining the corrosion rate, from which the remaining life can be calculated. This will prevent failure of equipment and loss of containment of the product. It will also allow time to plan for replacement equipment in advance.

Detecting degradation early could also enable equipment owners or users to perform simple repairs such as paint to stop the progress of corrosion, De Beer adds. However, if identified too late, repair become more expensive, especially when grinding and welding is involved.

“Early detection is key to operating safely,” he comments, adding that predicting where the degradation will occur requires experience.

Further, De Beer notes that the South African Bureau of Standards is updating the national standards regularly, which ensures that pressurised equipment is inspected at regular intervals.

He explains that, in accordance with the Pressure Equipment Regulation and SANS 347, all pressure equipment has to be inspected by a competent person every three years. This inspection usually includes a hydrostatic test.

Additionally, non-destructive testing (NDT) could provide additional information that is relevant to the integrity of the equipment during this three-yearly inspection. He puts forward that the continuous professional development (CPD) system is being implemented by the South African Institute of Nondestructive Testing, to ensure that NDT technicians keep up to date with technology.

“The CPD system is already in place for engineers, doctors and accountants, among others. Inspecting equipment regularly is a win for any company owner or user. It keeps the equipment in good condition and will save money,” De Beer concludes.