Spray fluxing process uniformly applies flux solids to a SMD and through hole printed circuit board within a desired deposition range, and maintains that range over time before wave soldering . It is measured in micrograms of flux solids per in2 (or cm2). A flux manufacturer recommends flux deposition range of 1,000–1,500 μg/in2.
The job of flux is to remove metal oxides and nonmetallic compounds from interconnect surfaces. To do this job, it needs to be applied to all the metal surfaces to be joined. Therefore, spray fluxing process control also includes, “the ability of the fluxer to penetrate 100% of the plated-through holes.”
Most ordinary fluxers offer little or no process control. Foam fluxers are open vats exposed to the atmosphere in which flux evaporates causing its properties to change, resulting in poor soldering, excessive flux residue, and gallons of chemical waste. Nozzle spray fluxers are better, but have their own inherent problems. Most glaringly, nozzles clog disrupting the uniform application of flux. Fluxers with stationary heads make flux penetration of plated-through holes challenging at best. These under performing fluxing systems cost board manufactures thousands of dollars in wasted materials, rework, and production line downtime due to unnecessary maintenance.
Because of larger orifice size iminds technologies Ultrasonic nozzle does not clog over the period of a month after cleaning. Reduces flux usage by 80% and also reduces environmental pollution. It allows flux deposition density control. Iminds ultrasonic spray nozzle retrofit in to wave soldering machine.
The other applications includes: