The aerosol valve controls flow rate, atomization, and spray pattern. Standard valves work for most products. Specialty valves (foam, stream, mist) serve specific applications. OEM buyers must specify: flow rate (ml/sec), spray pattern, actuator type, and propellant compatibility.
How Aerosol Valves Work
An aerosol valve has four components: The stem (opens when pressed, releases product), the gasket (seals the can, prevents leaks), the spring (returns stem to closed position), and the dip tube (draws product from bottom of can). When you press the actuator, the stem moves down, opening the orifice. Propellant pressure pushes product up the dip tube and out through the orifice. The size of the orifice determines flow rate. The actuator shape determines spray pattern.
Valve Types and Flow Rates
Standard valves have flow rates of 0.5-1.5 ml/sec. Fine mist valves (0.3-0.6 ml/sec) for products needing thin, even coverage. High-flow valves (1.5-3.0 ml/sec) for thick coatings and lubricants. Foam valves use a wider orifice and special actuator to create foam. Stream valves produce a narrow, targeted stream for precision applications. The dip tube length matters -- standard tubes reach the bottom of the can. For tall cans, extended dip tubes are required.
Actuator Types: Fan, Cone, Stream, Mist
Fan actuators produce a flat, wide spray pattern -- ideal for paints and coatings. Cone actuators produce a circular pattern -- good for lubricants and cleaners. Stream actuators produce a narrow jet -- for precision application and hard-to-reach areas. Mist actuators produce ultra-fine droplets -- for products needing thin, even coverage. The actuator orifice size ranges from 0.2mm (ultra-fine mist) to 2.0mm (stream). For OEM buyers, specify the actuator type based on the end-use application.
Propellant Selection
LPG (propane/butane mix) is the most common propellant -- cheap, reliable, works with most formulations. Dimethyl ether (DME) is used for water-based formulations -- it mixes with water. HFO-1234yf is the eco-friendly option -- low GWP, but expensive. Compressed air/CO2 is used for some food and personal care products. The propellant ratio (paint:propellant) determines spray pressure and atomization. Typical ratios are 60:40 to 80:20 (paint:propellant). Higher propellant = finer atomization but shorter spray duration.
What is the most important part of an aerosol can?
The valve. The can body is just a container. The valve determines spray quality, consistency, and user experience. A premium valve on a standard can outperforms a standard valve on a premium can. For OEM sourcing, invest in quality valves (Lindal, Aptar, or equivalent) and test multiple actuator options before finalizing the design.