Coating thickness measuring technology is often associated only with the measurements of paint coating like those taken for damage assessment of cars. Nowadays however, modern coating thickness measuring systems are successfully used for inspecting the corrosion protection of bridges, ships, pipelines and all the other steel constructions that are so crucial to all our safety.

The radio-based coating thickness measuring probe QNix® sat: measure where the thump fits

CORROSION is a considerable risk and safety factor causing losses in the billions. Yet, those in charge still underestimate its economic significance regarding cost and growth. Each year, economies, states, communes and industries have to bear considerable losses due to RUST. Often those losses amount to several times the national economic growth (275 billion Dollars in the US / About 70 billion Euros in Germany).

RUST: cause of damage in the billions, defects and disasters.

In 2010, the German Technical Inspection Association (TÜV) reported CORROSION of frameworks and load bearing parts of cars as one of the main causes for defects; an enormous safety risk. RUST can be the reason for automobile manufacturers recalling their cars, for ICEs to break down, bridges and buildings to collapse. Rust can cause catastrophic tanker accidents, leaking pipelines and incidents in nuclear power plants.
Multi-layer coating material provides effective protection against such corrosion. To ensure long-term protection of particularly crucial steel constructions, Duplex coating systems, based on a galvanizing and an epoxy-based coating, are used. However, even that does not keep corrosion at bay for all eternity, since “rust never sleeps“. While DUPLEX coating thickness measurements reduce safety risks, only regular inspections with state-of-the-art Duplex coating thickness gauges ensure the protective function of the coating. Regular inspections also help recognizing dangers to safety and environment in time to prevent disasters and avoid losses in the billions.
The protective function of modern coating material on steel depends significantly on its impermeability against affecting media. If pores have formed, unnoticed subsurface corrosion will start spreading and will destroy the coating. The careful selection of adequate coating material and the quality of the coating process are of the utmost importance to guarantee the durability of the applied layers and thus the safety of steel constructions. This quality of the coating, however, has to be checked regularly.
To ensure the quality and proper protective function of a Duplex system, i.e. the coating thickness of the galvanizing and the epoxy-based coatings on the steel surface, both coating layers have to be inspected and measured using specific coating thickness gauges with combined Duplex measuring modes.

Modern multi-layer measurements using wireless and interchangeable probes.

The latest coating thickness gauges, such as the QNix® 8500 measuring system from AUTOMATION Dr. Nix, Germany, offer a combined measuring mode. This provides a convenient way of measuring and storing the double coating (galvanizing and upper epoxy-based layer) in one single measurement process. It also allows for simultaneous analysis of both layers’ coating thickness. In addition to multi-layer measurements, the interchangeable probes from AUTOMATION Dr. Nix allow for flexible use depending on the measuring task. They offer additional advantages for effective and safe quality control using wireless, radio- based measuring technology. Here especially, the wireless probes of the latest modular measuring system QNix® 8500 have proven themselves in practical application, for instance, when measuring large steel constructions such as bridges, ships, polygons, wind energy plants or antennae that can often only be safely inspected while climbing. The small, only thump-sized, probes allow for safe climbing with both hands, as they are easily fixed to a wristband and because all measurements are transmitted to the gauge via radio.

Summarization: The quality of Duplex corrosion coatings and thus the safety of steel constructions have to be inspected regularly. The latest coating thickness gauges from AUTOMATION Dr. Nix allow for such safety inspections to be achieved completely and effectively on the object directly, using radio-based Duplex probes or combined measuring probes. Fast measuring as well as convenient and miniaturized probes enables users to carry out their coating thickness and corrosion inspections in many situations even under difficult conditions while still complying with current safety regulations and without any cable hindering their work.

To read the full report, published July 2010 in the German “Metall“ magazine, please visit:
http://www.metall-web.de/