Coating inspection services or verifications are commonly requested quality assurance evaluations used when edifices and new constructions are undergoing replacement or repairs of interior of exterior coatings or liners.
Coating inspectors are accountable for the execution and the recording of simple non-destructive evaluations of liquid and non-liquid coatings applied in any form onto metal or other substrates.
ATS Provides the Following Coating Inspection Services for our Clients:
- Dry Film Thickness
- Wet Film Thickness
- Holiday Detection
- Surface Profile Measurement
- Environmental Readings for Coating Application
Dry Film Thickness
One of the most precise measurements of our coating inspection services is the Dry Film Thickness test. Dry Film Thickness inspections deliver critical information about the projected life cycle of the coating and confirms if there are any violations with the required project specifications. It is because of the influence and effect on the quality, process and cost of the final product that Dry Film Thickness is considered to be a key requirement and the most objective element of the coating production industry.
Dry Film Thickness or mostly known as DFT, is the measure of the applied coating over the surface, regardless whether the coating contains a single layer or multiple layers. The coating must be cured (or completely dry) before DFT can be performed. The thickness of the coating is contingent on the adequacy of the surface preparation and the way the paint is applied to the substrate.
Wet Film Thickness
There is also another way to measure coating thickness in coating inspection. Coating thickness can be analyzed immediately upon application on to the surface and that method is called Wet Film Thickness. It is performed with MIL Gauges, Notched Gauges and/or Step Gauges.
Wet Film thickness testing is another outstanding method to measure for coating and quality control and it is also another method to evaluate and examine coatings. Wet Film thickness testing is a way to get an immediate response on the quality of the coating applied, and will deliver information in the event improvements are needed during the application process.
The Dry Film thickness could be forecast by performing or using the Wet Film Thickness method. It could be calculated by using the solids to liquids ratio method (or volume solids content). Utilizing the Wet Film Thickness method also assists in cost control by making sure the correct coating quantity or volume is applied to the surface, enough material is ordered, and adequate protection for wear, corrosion and damage is obtained.
Holiday Testing
Another nondestructive test method utilized in coating inspections is Holiday Testing. It is used to locate discontinuities in the coating such as voids or pinholes. The test consists of establishing an electric circuit to find out if the current flow through the coating completes the circuit. The test is mainly performed to find coating film breaks or subsurface air bubbles that are not visually noticeable.
Holiday testing is mostly used on buried structures, tank interiors, and vessels of chemical storage since it is critical to maintain sufficient protection in corrosive environments. Continuity testing is another common name for Holiday Testing.
Commonly Used Testing Specs:
- ASTM D1212-91: Standard Test Methods for Measurement of Wet Film Thickness of Organic Coatings
- ASTM D3276-15: Standard Guide for Painting Inspectors (Metal Substrates)
- ASTM D4138-07: Standard Practices for Measurement of Dry Film Thickness of Protective Coating Systems by Destructive, Cross-Sectioning Means
- ASTM D4414-95: Standard Practice for Measurement of Wet Film Thickness by Notch Gages
- ASTM D4541-09: Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers
- ASTM D5162-15: Standard Practice for Discontinuity (Holiday) Testing of Nonconductive Protective Coating on Metallic Substrates
- ASTM D7091-13: Standard Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic Nonconductive Coatings Applied to Non-Ferrous Metals.
ATS’ Commitment to Quality
To ensure our clients enjoy services of the highest quality, ATS maintains an ISO 9001:2015 registered quality management system and employs NACE certified coating inspectors. By following the principles outlined in these internationally respected standard organizations for quality assurance, we are able to continually improve our services for our clients’ benefit.
If your company needs a comprehensive array of coating inspection services, contact ATS today — we take a closer look!
