Application Guidelines for Airless High-Pressure Spraying of Epoxy Floor Coatings

In the construction of Jinfeng epoxy flooring, high-pressure airless spraying delivers a better surface appearance than roller coating, featuring higher gloss and superior wear resistance — since airless sprayed floor paint requires almost no thinner addition.

During spraying, the spray gun shall be kept perpendicular to the substrate surface, maintaining a distance of 30–40 cm.

Move the spray gun steadily at a uniform speed and keep it parallel to the floor surface to avoid paint accumulation and uneven coating. Maintain the spraying distance and vertical angle by body posture; move the gun with the coordination of body and arm instead of twisting the wrist, while keeping the wrist flexible.

Each spray pass shall overlap the previous one by about 20%–30% to form a complete and uniform coating. When spraying corners, aim the spray gun at the center of the corner to ensure even coverage on both sides.

Always pull the trigger when the spray gun is in motion, and release the trigger while still moving the gun. This avoids excessive paint buildup on the surface.

With the same spray width, a larger nozzle orifice results in a thicker film build.

With the same nozzle orifice, a wider spray width produces a thinner film build.

Precautions for High‑Pressure Airless Spraying

(1) Spraying Pressure and Flow Rate

For a specific model of airless spraying equipment, when coating viscosity and inlet compressed air pressure remain constant: the higher the flow rate, the lower the spraying pressure. When the inlet compressed air pressure rises, both spraying pressure and flow rate increase accordingly.

(2) Coating Viscosity and Spraying Pressure

Low‑viscosity coatings generally adopt a pressure ratio of 23:1 or 32:1, while high‑viscosity coatings usually require a pressure ratio around 45:1. However, pressure should not be increased blindly. When spraying high‑viscosity coatings, replacing with a larger‑orifice nozzle is also recommended.

(3) Nozzle Selection

Before high‑pressure airless spraying, select a nozzle with suitable orifice size and spray pattern according to the coating type and construction substrate.