Nozzle/Spray Head

The nozzle/spray head is a critical component of electrostatic spray guns, serving as the final discharge point for coating materials. It atomizes liquid coatings into fine droplets and directs them toward the workpiece while imparting an electrostatic charge to the particles for improved transfer efficiency and coating uniformity. This component is available in materials such as stainless steel, tungsten carbide, and ceramic, each selected based on wear resistance and chemical compatibility. Key parameters include flow rate (0.5–2.5 L/min), spray angle (30–90°), orifice diameter (0.5–2.0 mm), operating voltage (24 V DC ±10%), operating temperature (-40–85°C), ingress protection (IP54–IP65 per IEC 60529), material grade (316L per ASTM A240), and weight (0.15–0.35 kg). These values are reference ranges and must be verified for the specific model and application. The nozzle's design influences coating thickness, transfer efficiency, coverage area, and atomization quality. Proper selection requires consideration of the coating type, desired film build, part geometry, and electrostatic charging requirements. Interfaces include the fluid inlet, electrical connection, and mounting to the spray gun body. Verification questions should address compatibility with the gun model, material certification, and performance testing under actual operating conditions. Maintenance signals include inconsistent spray patterns, reduced transfer efficiency, or visible wear on the orifice. Failure boundaries include exceeding pressure or temperature limits, which can cause material degradation or seat leakage. Always confirm model-specific values and standards with the legal manufacturer or supplier.

The nozzle/spray head receives pressurized coating material from the gun's fluid system and forces it through a precisely engineered orifice. This creates shear forces that break the liquid into fine droplets. Simultaneously, the component is electrically charged (typically through induction or direct contact) to impart an electrostatic charge to the atomized particles, which are then attracted to the grounded workpiece. The spray angle and droplet size are determined by the orifice geometry and fluid pressure.