Visual Plus 3 Eddie Current Testing

What Do We Do?

As accredited service providers, National Hydro Cylinder Testing Services technicians are here to perform your Scuba Visual Plus Eddie Current Cylinder Testing in Adelaide.

We operate and manage an approved gas cylinder test station, number 720.
We are focusing and specialising in all Scuba Cylinder Tests and Refills aspects.

With more than 35 years of experience, we can help you with your Scuba cylinders.

When you work with us, you can be assured you will receive high-quality service and care from our friendly technicians, who assist you with all your needs to help you with your Scuba Visual Plus Eddie Current Cylinder Testing Requirements in Adelaide.

man testing scuba cylinder
Scuba Cylinders

Visual Plus 3 Cylinder Inspection

Our licensed gas cylinder test station and capabilities allow us to test and refill high-pressure breathable air gas cylinders ranging from air bank and bailout cylinders to aluminium and steel scuba cylinders.

Endorsed by significant cylinder manufacturers, including Luxfer, Worthington SCI, and Catalina, Visual Plus 3 is the best inspection technology − and because of its exclusive software and versatile calibration features, Visual Plus 3 will be the equipment of choice for inspecting new aluminium alloys in the future.

Visual Plus is a non-destructive testing (NDT) device that utilises eddy currents to detect neck and shoulder cracks, folds or other similar imperfections in aluminium cylinders such as scuba, SCBA (all metal, hoop-wrap or full wrap), beverage, medical, industrial gas cylinders, fire extinguishers, etc.

An electromagnetic wave is introduced into the metal of the vessels near the area, which is desirable to inspect for imperfections (the threaded area).

The wave causes currents to flow circularly in the metal. They are called eddy currents because the flow is circular. An imperfection can increase the path the currents have to flow, making the material appear higher in resistance in that region where the fault is present.

This generates a spike in the computer-generated report, which alerts the technician to a problem that requires further investigation. Hydrostatic testing alone does not reveal cracking in aluminium cylinders’ neck/shoulder area unless they are leaking.

Visual Plus identifies 100% of these defective cylinders.

For all your Scuba Cylinder Testing & Refills in Adelaide.
Call us today on 1300 883 473 or
email us

Sustained Load Cracking “SLC”

Aluminium 6351-T6

6351 Aluminium Cylinders are generally recommended to be replaced with new ones. However, they can still undergo a Hydrostatic and Eddie Current Test if the owner wishes to continue to use them.

Dive Shops and Scuba refillers have the right to refuse air fills as the cylinders pose a risk due to SLC developing and the cylinder experiencing a catastrophic failure.

In August 2016, a worker suffered severe injuries, including partial leg amputation, when an aluminium scuba cylinder catastrophically failed, exploding while being filled—pieces of a failed aluminium cylinder. The failed cylinder was manufactured in 1987 from aluminium alloy 6351–T6. However, the investigation into this incident has not yet determined the cause of the failure. Investigative work into similar losses worldwide has shown that failure is typically caused by sustained load cracking (SLC) in the neck and shoulder area of the cylinder. The problem of SLC only affects cylinders made from aluminium alloy 6351–T6 and is not limited to any one cylinder design or manufacturer. Failures have typically occurred when filling Scuba/SCBA and oxygen cylinders. Catastrophic failures have occurred at or below the working (fill) pressure. Additional control measures for cylinders from the above alloy have been introduced, including the eddy current non-destructive testing (NDT) requirement.

  • For Scuba and SCBA cylinders manufactured from aluminium alloy 6351-T6, eddy current testing must follow the manufacturer’s instructions. Without the manufacturer’s instructions, requalification should include eddy current inspection testing and a visual inspection of the internal shoulder and neck thread area.
  • For cylinders that pass requalification, include in the cylinder test report whether requalification has included eddy current testing.
  • If changing the valve, ensure the valve thread matches the cylinder thread, e.g., tapered or parallel threaded.
  • Where cracks are evident during the inspection, the cylinder must be condemned.

fire extinguisher testing Safety Alert,  Safework NSW

Video explaining “SLC” with SCUBA Cylinders 

Our Services

The Company offers various services to the Scuba Community within Australia.

  • Air Bank Cylinder Testing
  • Eddie Current Testing
  • Hooker Air Line Pressure Testing
  • Hydrostatic Pressure Testing
  • Scuba Cylinder Repaints & Repairs
  • Scuba Cylinder Refills

Scuba Cylinders Out Of Date & Need A Test?