Defining Coating Inspection & Its Need

Coating Inspection

In the field of manufacturing, you already know how important it is to follow the correct sequence of different operations in every aspect. There are various types of coating inspections which fall in the category of NDT services. These processes are executed by highly skilled and trained personnel to read the classification and efficiency of the material. The techniques that are included in the inspections are typically based on different welding codes like, ISO, ASME, API, EN and Australian Standard.

Before conducting any coating inspections, magnetic particle and liquid penetrant testing are done. However, this depends on the type of composition of the materials and the achievement the owner is looking for.

What is the need for coating inspection?

Coating inspection is typically used to figure out ductility, hardness and tensile strength involving the parts that take most of the stress. Thus, without breaking or damaging the material, with the help of NDT, it becomes easy to determine the breaking point. This means that prevention of major accidents becomes easy while maintaining a safe working ground.

Inspection procedure

The procedures of coating inspection include electromagnetic waves, used to gauge the thickness of a specific coating, and measuring the heat distribution (thermography) of the substance. This process determines the quality of the coating (binding to its substrate).

Also, lasers are used to measure the profile of the surface without physically harming the substrate. In the industry of coating inspection, sometimes the use of permanent base coating helps to determine the ductility of the material. The applied coating itself fluoresces under a black light. This allows inspectors to determine the imperfections in the base quite easily.

Gauges and industrial coatings

Various electronic gauges are the most significant contribution to the field of coating inspections. These equipment nowadays are standard inspection devices for quality assurance and control in the industry. These tools are also capable of performing other functions like, ultrasonic waves to figure out the dry film thickness of an applied coating.

The importance

Coating inspection is one of the most important sections in the field of NDT. To protect the superiority of the material, accurate measuring is important, which can only be done through qualified inspectors in Melbourne. They precisely allow the industry to perform as per the mentioned specifications to avoid forensic complications.

Before hiring any NDT company, it’s crucial to check whether or not they are qualified from the WTA and perform any documentation service for inexperienced welders.


The Working Processes Of A Good Welding Inspector

Welding InspectionA typical welding inspector is entrusted with the task of overseeing each and every activity as well as duty of a welding staff so as to ensure that all things are in ideal working manner. The job of the professional is making sure that welders conduct their tasks within the fixed deadline and quality specifications. It is also important for him or her to possess advanced knowledge about welding processes and procedures in order to be capable of providing guidance in problematic scenarios.

A good welding inspector is also expected to visually assess the welded products in order to check for room to improve or eliminate deformities. They can even utilise stress equipment for putting stress on weld joints. They are responsible for collecting records of readings from tests for future reference. They primarily work in the field of manufacturing processes and building construction.

Let’s take a quick look at the the different duties performed by professionals of welding inspection in Melbourne:

Welding Inspection

  • Interpretation of purpose as well as requirements of the various standards, codes and specifications.
  • Making sure that a specific process is available, approved and employed in the production.
  • Verifying the availability of enough legitimate welder approvals, and also making sure that only the approved ones are utilised in production.
  • Checking the parent material against markings and documentation.
  • Inspecting the correctness of different welding consumables like gases, fluxes, filler wires, electrodes, consumable inserts, etc.
  • Inspecting that the fit-up, weld preparations and dimensions are according to the specifications.
  • Verifying that the required preheat complies with the particular procedure.
    Assistance & agreement along with preparation of ITPs or Inspection & Test Plans.
  • Surveillance at the time of welding for ensuring compliance with required procedures like preheat, post heat and interpass temperature control requisites.
  • Inspecting to ensure conduction of post weld heat treatment as per specification requirements.
  • Dimensional check and visual inspection of the completed weld against specification drawings and requirements.
  • Utilising various methods of non destructive testing like magnetic particle, ultrasonic inspection, radiography or liquid penetrant to study their results on a specific welding work.
  • Evaluating and preparing inspection reports for a client or employer.
  • Maintaining each and every record of all inspections that they have carried out.

So, basically, these are the things that comprise the regular working processes of a certified welding inspector in Melbourne or anywhere else in Australia. They play a very important role in ensuring the quality & safety of different manufactured products.

What Does A Coating Inspector Actually Do?


To put it in the simplest of terms, a coating inspector or CI is essentially a professional who possess certification and training from programmes like NACE Coating Inspection Programme. Technically speaking, the fundamental job of any coating inspector is to assess the conditions during which a spray, paint or coating has to be applied. In addition to that, he or she must also suggest the kinds of coating which would safeguard the material in question against detrimental corrosive environments.

In order to be a fully qualified coating inspector in anywhere within Australia, an aspiring individual first has to undergo a specific formal certification programme recognised by the industry. The courses encompassed in the programme are designed for training an individual in standard coating inspection techniques or improving the quality of their amateur skills.

Basically, there are two kinds of inspectors who check corrosion protection systems on various materials – Level 1 and Level 2:

Level 1 – Coating inspectors belonging to Level 1 are knowledgeable of techniques used for preventing corrosion using paints & coatings, inspection and quality control, information about how to conduct surface inspection for coating application after surface preparation, coating specifications, project assessments and safety standards.

Level 2 – Level 2 qualified inspectors are educated about responsibilities and roles of a CI, role of coating manufacturer for any pertinent project, techniques utilised for coating application, evaluation of those techniques, preparation of inspection plans, and handling unusual situations like too much or less coating, etc.

However, no matter what level a CI in Melbourne belongs to, he or she always has to ensure that the quality of a finished product is in compliance with industry standards. Quality control initiates with assessment of the product using a number of methods that can help to decrease factors which adversely affect quality. Certain methods associated with quality control of corrosion protection coatings include failure testing, statistical process regulation, acceptance sampling and analytical quality control.

Corrosion of various materials can lead to mishaps and financial meltdown. As such, coating inspectors play a very important role for manufacturing industries. Their knowledge proves to be important at every step of corrosion protection coating application – right from deciding the most suitable protection up to checking quality of the coating. In case additional safeguarding methods are necessary, a CI recommends and encourages them too. In other words, they serve as a backbone for ensuring consistency of quality in case of manufactured products.

Measurement Of Thickness Of Duplex Coatings

For corrosion-resistant coatings, thickness of each single coating is a very important factor for determining quality. And measurement of that thickness is usually obtained by using non-destructive methods. Different kinds of duplex coatings are normally classified as per their measurability. They have been described below in detail:


  • Those comprised of a zinc-nickel or zinc-iron alloy layer and an organic layer. Due to their high costs, they are usually found on components of automobiles for preventing corrosion entirely.
  • Systems installed on piping like shopping carts, brake lines, certain household appliances having zinc thicknesses of 30 microns or less and organic coating of plastic or paint with thicknesses of 200 microns or less.
  • Hot-dip galvanized steel components having zinc layers denser than 80 microns, paint layers with thickness of over 85 microns and distinguishing iron-zinc diffusion zones. They are generally found in steel construction.
  • Versions having zinc thicknesses from 0 to 10 microns, deposited either in a dip bath or galvanically, and also paint thickness within 150 microns. They are common in vehicle body manufacturing.

As duplex systems combine metallic and organic coatings, the methods used for measuring them involve usage of economical and non-destructive instruments that are easy to handle. Such coating inspection techniques incorporate eddy current and magnetic induction test methods. The latter test procedure is normally performed as per DIN EN ISO 2178 for measuring nonmagnetic coatings primarily applied to iron, steel and other ferrous metals. On the other hand, the eddy current method test is conducted as per the DIN EN ISO 2360 to measure non-conductive, non-magnetic coatings on various non-ferrous metals.

Eddy current method, which is phase sensitive, necessitates the metal coating to have significant electrical conductivity so that the current can actually develop. However, zinc coatings often exhibit lesser electrical conductivity of below 1MS/m due to having crystalline structure. For carrying out thickness measurement on basis of phase measurement, frequencies above 10 MHz are used.

In general, large components present within practical measurement amalgamate magnetic induction with phase sensitive eddy current. With extra action input from the operator, the measurements are performed using both methods successively after placing a probe. After that, the data of the measurement is collected suitably.

Thus, these are the industrial processes used for measuring thickness of duplex coatings. The above explanation is a simple demonstration of the methods involved. If you want to know more about them, look up informative articles over the Internet or get in touch with an expert.