In the dispensing industry, jet valves are commonly used in high-speed, high-precision applications. Unlike needle valves, jet valves rely on high-frequency switching to “shoot” adhesive, making them ideal for micro-volume, high-speed dispensing.

The core principle of jet valves is to use a rapidly moving needle or vibrating diaphragm to form continuous and stable micro-droplets of adhesive. With millisecond-level response, they perform exceptionally well in high-speed SMT, microelectronics packaging, and similar scenarios. Jet valves are often used to handle 0.001–0.01 mL micro-drops in consumer electronics, LED packaging, and miniature medical devices, ensuring accuracy and consistency.

Structurally, jet valves consist of a high-frequency drive mechanism, a needle or diaphragm, the valve body, and a micro-nozzle. Drives are typically pneumatic or piezoelectric, requiring high responsiveness and repeatability. Nozzle diameters usually range from 0.1 to 0.3 mm to ensure droplet precision. Proper adjustment of pressure and drive parameters according to adhesive viscosity, dispensing frequency, and nozzle size is essential to prevent inconsistent droplet sizes or dripping.

Compared to needle valves, jet valves dispense smaller, more precise amounts but demand stricter control of adhesive viscosity and particle size. High-viscosity adhesives or those containing large particles can clog nozzles and disrupt continuous dispensing. Therefore, jet valves are almost always used with filtration and degassing systems to ensure adhesive purity. Additionally, jet valves have minimal post-dispense suck-back; residue control relies on programmatic high-speed needle operation rather than mechanical retraction, unlike screw or needle valves.

In practical projects, jet valves have been applied in Mini LED encapsulation. Each LED chip requires only a tiny amount of epoxy, with precise placement and shape. Traditional needle or time-pressure valves cannot achieve this accuracy. Optimized jet valves can dispense dozens to hundreds of chips per second, with stable, consistent drops, significantly improving production efficiency and yield.

Despite their high precision, jet valves come with higher costs and maintenance requirements. Needle or diaphragm wear directly affects droplet accuracy, requiring regular inspection and replacement. Stable air supply and control systems are critical, as minor fluctuations can cause inconsistent dispensing or dripping. Jet valves are best suited for applications demanding micro-volume, high-speed, and high-consistency dispensing rather than all dispensing scenarios.

Overall, jet valves play an irreplaceable role in high-speed precision dispensing. Selecting the right valve according to adhesive properties and process requirements ensures optimal precision and efficiency. In practice, proper technique and process understanding are just as crucial as the tool itself for successful dispensing.