Flat-fan nozzles arrayed in a manifold header are the standard choice for uniform film coating on moving webs, strip, and conveyor lines. They produce a controlled fan-shaped spray with a relatively flat distribution curve, which makes them easy to overlap for full-width coverage. Nozzle spacing, stand-off distance, operating pressure, spray angle, and orifice size all need to be matched to your target coat weight and line speed. Hydraulic atomizing nozzles are preferred when coat weights are very low or when fine droplet size is needed to minimize impingement effects.

Overspray reduction comes from several levers: right-sizing orifice diameter to the required flow rate at the lowest pressure that maintains pattern integrity, minimizing stand-off distance to reduce drift (especially with fine droplets), and synchronizing nozzle on/off gating with line start and stop events. Hydraulic atomizing nozzles at minimum operating pressure produce larger droplets with less drift tendency than higher-pressure operation. Air-atomizing nozzles offer the most droplet size control and can meaningfully reduce overspray compared to hydraulic nozzles for viscous materials.

In many cases, yes — provided the nozzle body and seal materials are chemically compatible with both coating systems. 316L stainless steel bodies are compatible with most water-based and many solvent-based coatings. The critical check is the seal: EPDM and silicone have limited resistance to aromatic and ketone solvents, while PTFE and Viton offer broader solvent resistance. Verify seal compatibility against your specific solvent chemistry before switching fluid types on the same nozzle.

For coating fluids containing abrasive particles, fillers, or pigments, hardened orifice materials are essential to maintain accurate flow rates and pattern quality over time. Tungsten carbide orifice inserts provide the highest wear resistance and are preferred for heavily loaded abrasive systems. Ceramic inserts offer good wear resistance at lower cost for moderate abrasion levels. Standard stainless orifices enlarge progressively in abrasive service, causing flow rate creep and pattern distortion — the orifice, not the body material, is what matters most for abrasion resistance.

Start with your required coat weight in grams per square meter, line speed in meters per minute, and web or surface width. These define the total fluid flow rate needed per meter of width. Divide by nozzle count per meter to get individual nozzle flow rate, then select an orifice size that delivers that flow at an appropriate pressure for your fluid viscosity. Stand-off distance sets spray width per nozzle; spacing is then set so adjacent spray widths overlap 10–30%. NozzlePro application engineers can work through this calculation with your specific parameters.

Hydraulic atomizing nozzles use fluid pressure alone to break the liquid into droplets — simpler, no compressed air needed, and effective for low-to-medium viscosity fluids at moderate coat weights. Air-atomizing nozzles use compressed air to atomize the liquid, giving much greater control over droplet size across a wider viscosity range and allowing very low coat weights with fine, consistent droplets. Air-atomizing is preferred for high-viscosity coatings or applications where droplet uniformity is critical, though it requires a compressed air supply and runs at higher operating cost.