Surface Treatment

Reasonable and rigorous pretreatment procedures are critical to guarantee paint adhesion and durability. We have undertaken projects for port machinery, paper-making machinery, solar and wind power transformer tanks. Such equipment is widely deployed in coastal regions, high-acid environments and sun-exposed Gobi areas, where stringent anti-corrosion requirements apply.

We own large sandblasting booths and pickling & phosphating tanks in-house to deliver robust protection against highly corrosive conditions. Our workers regularly attend centralized training hosted by major paint manufacturers to ensure painting operations strictly follow specifications. For quality inspection, we are equipped with coating thickness gauges and support third-party type tests.

Painting Coating Processes

• Pre-treatment: Remove oil, rust and scale by sandblasting or chemical cleaning to ensure clean and active substrate surface.

• Inspection: Check workpieces for cracks, pits and sharp edges before coating.

• Masking: Protect threads, holes and assembly surfaces against paint/powder contamination.

• Surface preparation & drying: Fully dry parts to eliminate moisture before coating.

• Coating application: Liquid painting or electrostatic powder spraying under controlled environment.

• Curing: Oven curing according to specified temperature and time profile.

• Post inspection: Check coating thickness, adhesion, appearance and run tests for defects.

• Finishing & packaging: Touch-up for minor flaws and protective packaging.

Powder Coating Processes

• Degreasing: Remove grease and contaminants on carbon steel surface.

• Pickling: Immerse workpieces in acid tank to strip rust, mill scale and welding oxides.

• Multi-stage rinsing: Wash off residual acid to prevent over-corrosion.

• Neutralization: Neutralize leftover acid.

• Surface conditioning (activation): Refine metal grains for consistent phosphate film.

• Phosphating: Form dense zinc phosphate conversion coating on substrate.

• Final rinsing & passivation sealing.

• Drying: Completely dry workpieces before coating.

• Masking: Protect threads, holes and mating surfaces.

• Electrostatic powder spraying: Powder adheres evenly to grounded metal in spray booth; overspray recovered for reuse.

• Oven curing: Heat at 160–200°C for 10–20 minutes, powder melts, flows and cross-links into tough coating.

• Cooling: Cool naturally to room temperature.

• Inspection: Check coating thickness, adhesion, color and surface defects.

Stainless Steel Sandblasting

Stainless steel sandblasting is a mechanical surface pretreatment method. By spraying qualified abrasive media under controlled pressure, it removes welding discoloration, oxide scales and surface contaminants without damaging the base metal. It creates a uniform matte finish, improving surface cleanliness and aesthetic performance.

This process is widely applied to stainless steel equipment and structural parts for papermaking, energy and marine industries. It eliminates welding stains and surface blemishes, forming a consistent textured surface. Our workshop adopts strict masking and dust cleaning procedures to protect precision threads and mating surfaces. After blasting, parts are fully cleaned and inspected to avoid embedded grit and secondary pollution.