Inspection of Lining Application in Steel and Concrete Equipment – NACE SP0288
Lining Material – Section 4
The lining material used shall be verified to be that which has been specified.
Lining material storage procedures and conditions shall be verified to be in accordance with lining manufacturer’s requirements.
Batch numbers of all components of a lining system shall be recorded.
The age and shelf life of lining materials shall be verified. Lining materials that have surpassed their shelf life shall not be used.
Mixing of lining materials shall be verified to be in accordance with the lining materials manufacturer’s written instructions and that the amount and type of thinner used for reduction are as specified.
Paints and thinners shall be stored in well-ventilated buildings at storage temperatures as recommended in the manufacturer’s data sheet.
Protecting Edges, Crevices, and Irregular Steel Surfaces by Stripe Coating – SSPC-PA Guide 11
Background – Section 2
Sharp edges, outside corners, crevices, and welds are often sites where coating failures and corrosion begin due to reduced coating barrier protection (see Figure 1). Reduced coating thickness on these surfaces can be a result of application of inadequate amounts of coating, but the surface tension of the wet coating or coating shrinkage during the drying/curing process can also pull the film away from edges. Sharp edges resulting from cutting, burning, and shearing are especially difficult to coat adequately. Bolt threads combine the adverse effects of sharp edges and crevices.
Stripe Coat Application – Section 4
A “stripe coat” is a coat of paint applied only to edges, welds, outside corners, bolt heads and threads, and crevices, either before or after a full coat is applied to the entire surface. These areas are difficult to coat due to coating shrinkage during cure. Shrinkage pulls coating away from sharp edges, resulting in low dry film thickness. Wet coating may flow over rather than into crevices. This results in a temporary bridge over the crevice that disappears as the coating cures and shrinks, leaving the crevice interior unprotected. Both areas are susceptible to premature corrosion. The practice of applying a “stripe coat” to such areas is frequently referred to as “striping.”
Conventional Air Spray
Gun
Fluid Tip
Air Cap
Air Hose ID
Material Hose ID
Atomizing Pressure
Pot Pressure
Compressed Air Source
Agitator
Airless Spray
Pump Ratio
Pressure
GPM Output
Tip Size
Material Hose ID
Filter Size
Plural Component Spray, Fixed Ratio
Drum Heaters
Hardener feed pump
Resin feed pump
Proportioning pump
In-Line Heaters
Material Hoses
Mixer manifold
Solvent Pump
Compressed Air Source
Plural Component Spray, Variable Ratio
Air Motor(s)
Primary Pump
Secondary Pump
Ratio Adjustment
Mix Manifold
Solvent Pump
Ratio Test, Pump and Metering Test, Mix and Integration Tests