surface profile measurement rough pitted steel

Surface Profile Measurement Options on Rough/Pitted Steel Surfaces

Introduction Surface profile is defined as a measurement of the maximum peak-to-valley depth generated by abrasive blast cleaning and impact-type power tools. These operations effectively increase the surface area and provide an “anchor” for the applied coating system. The surface profile depth must be compatible with the total coating system thickness; typically, the thicker the coating system, the deeper the surface profile. For example, a 3-coat 15 mil system may require a 2-3 mil surface profile, while a 40-mil coating...

scanning probe

Using Scanning Probe Technology to Measure Coating Thickness

Introduction Coating thickness measurement is one of the most common quality assessments made during industrial coating applications.  SSPC-PA 2, Procedure for Determining Conformance to Dry Coating Thickness Requirements is frequently referenced in coating specifications.  As SSPC-PA 2 has evolved over the past four decades, a number of procedures and measurement frequencies are referenced in both the mandatory portions of the standard and in the non-mandatory appendices.  While the measurement frequencies were never intended to be a statistical process, it is helpful to...

wet film thickness gage

Calculating and Measuring Wet Film Thickness

Wet film thickness, or WFT is the measured thickness of any applied wet paint that is liquid-based.  A wet film thickness gage should be used by the applicator as the coating is being applied to ensure that the measurement is representative of the calculated wet film before significant solvent evaporation occurs. Even slight delays in taking wet film thickness measurements can result in false low readings, since the solvents may have evaporated from the film before the measurements are...

psychrometer

The Psychrometer Duel: Old School vs. New School

Why do we need to measure ambient conditions? Ambient conditions are the prevailing conditions of air temperature, the moisture content of the air (relative humidity), and the temperature at which condensation will occur (dew point).  Most coating specifications have set requirements for monitoring and documenting results for surface and air temperature, relative humidity and dew point.  These conditions are to be measured and recorded in the specific areas where surface preparation and coating application will occur, then compared to the...