Surface Profile Gauge
Pulley Shell Metal Preparation
Adhesion to metal surfaces is dependent on having surface preparation that allows the bonding system to obtain a strong chemical and physical attachment. Metal surfaces
are blasted to increase surface area with a surface pro le of 50-100um giving a good base for adhesion. After sandblasting, surface profile on pulley shell need to be measured using a digital surface profile gauge and results should be recorded.
Bonding at the primer/metal interface is by chemi-adsorption of the primer onto the steel surface. Shot blasting of the steel pulley shell improves adhesion by the following mechanisms:
- removal of surface contaminants such as rust, scale and dirt
- increase of the shell surface area aids the physical attachment of the primer to the steel.
- producing a positive electrical charge over the steel surface
METAL PREPARATION recommendation for best adhesion requires 50-100um surface roughness
PCWI DIGITAL SURFACE PROFILE GAUGE
Digital Metric/Imperial Surface Profile Needle Gauge. Also a Pit & Crack Depth Gauge.