IF 930

nozzle cleaner


Interflux® IF 930 cleans and de-oxidizes wettable nozzles of selective soldering systems. IF 930 replaces IF 920.

IF 930 syringes 2

Suitable for

  • Selective soldering is a soldering technology in electronics manufacturing, typically used for PCB designs with mainly SMD (Surface Mount Device) components for reflow soldering and only a few through hole components that cannot pass through the reflow soldering process. These are usually thermally heavy mass components like e.g. big transfo's or thermally sensitive components like e.g. film capacitors, displays,  connectors with sensitive plastic bodies, relays, etc... The selective soldering process allows to solder these through hole components without protecting or affecting the SMD components on the bottom side of the PCB.  The selective soldering process is very flexible as the parameters can be programmed for each solder joint separately. The main limitation of the process however is the throughput or the production capacity. This can be considerately improved when using a low melting point alloy that allows for faster soldering speeds increasing production capacity up to 100% (double). The process starts with the application of a liquid flux that will deoxydize the surfaces to be soldered. This flux is applied by a micro jet or drop jet fluxer that shoots little drops. The correct calibration and programming of this fluxer is essential to get good soldering results. A common mistake is that flux is applied outside of the contact area of the soldering nozzle. This flux will remain as an unconsumed flux residue. For some fluxes and sensitive electronic circuits this can lead to increased leakage currents and failure in the field. It is advisable to use fluxes that are specifically designed for selective soldering and that are absolutely halogen free. The IPC classification for fluxes allows up to 500ppm of halogens for the lowest activitiona class but also these 500ppm can be critical, so absolutely halogen free is the key word. The next step in the process is preheating. This process step evaporates the solvents of the flux and provides heat to support good through hole wetting of the solder. Soldering is a thermal process and a certain amount of heat is needed to make a solder joint. This heat is needed from the bottom as well as from the top of the through hole component to be soldered. This heat can be provided by the preheating and by the liquid soldering alloy. Some basic machines do not have preheating, they will have to apply all heat through the liquid soldering alloy and in general they use higher temperatures for soldering. A preheating unit is usually a short wave IR (infrared) unit that applies the heat from the bottom side of the PCB. In most cases, the time and power of the preheating can be programmed. For thermally heavy boards and applications, top side preheatings exist. Usually they are hot air (convection) units where the teperature of the air can be programmed. When using this unit, it is important to know if there are any temperature sensitive components on the top side of the board that might be affected by this preheating.  Several systems for soldering exist. The one where the PCB board is standing still and only the soldering nozzle is moving is definitely preferred as all G-forces should be avoided when the solder solidifies. In the soldering step, a liquid soldering alloy is pumped through a soldering nozzle.There are different nozzle sizes and shapes available, wide nozzles, small nozzles, long nozzles and short nozzles.  Depending on the components to be soldered, one is preferred to another. In general wider nozzles and shorter nozzles give better heat transfer and are preferred. Smaller and longer nozzles can be used for situations with limited accessibility. Wettable nozzless are preferred to non wettable nozzles as they give a much more uniform flowing of the solder and more stable soldering results. Nitrogen flooding of the nozzle is advisable to have a stable flowing of the solder. The nitrogen is preferrably preheated because when not, it will cool down the solder and the PCB. The optimisation of the soldering program is essential for optimisation of the throughput/capacity of the selective soldering machine. This will focus on finding the minimal times and maximal speeds that give good through hole wetting in combination with no bridging.

Key advantages

  • Safe and easy one-step cleaning

  • In 2006 legislation restricted the use of lead (Pb) in electronics manufacturing.  However there were a lot of exemptions formulated, mainly due to the lack of long time reliablity experience with the lead-free alloys. This resulted in a lot of electronics manufacturing sites that were using both lead-free and Pb containing alloys in their soldering processes. For wave and selective soldering, a lot of electronic manufacturers desired the use of  the same flux chemistry with both types of soldering alloys. This was because they were familiar with the chemistry in terms of reliability. Also introducing new materials in a manufacturing can require a lot of paper work, extra storage capacity, etc...Although the lead-free alloys require higher operating temperatures than the Pb-containing alloys, by increasing the applied flux quantity in a lot of cases the same flux chemistry can be used for both alloys. However in some cases, usually when soldering electronic units with high thermal mass, it is not possible to use the same flux for both soldering alloys. In these cases, usually a flux with higher solid content is needed. A lot of solder wires and solder pastes are available with the same flux for both lead-free and SnPb-alloys.

  • Non abrasive

  • Absolutely halogen free soldering chemistry contains no intentionally added halogens nor halides. The IPC classification allows up to 500ppm of halogens for the lowest 'L0' classification. Soldering fluxes, solder pastes and solder wires from this class are often referred to as 'halogen free'. Absolutely halogen free soldering chemistry goes one step further and does not contain this 'allowed' level of halogens. Specifically in combination with lead-free soldering alloys and on sensitive electronic applications, these low levels of halogens have been reported to cause reliability problems like e.g. too high leakage currents.  Halogens are elements from the periodic table like Cl, Br, F and I. They have the physical property that they like to react. This is very interesting from the point of view of soldering chemistry because it is intended to clean off oxides from the surfaces to be soldered. And indeed halogens perform that job very well, even hard to clean surfaces like brass, Zn, Ni,...or heavily oxidized surfaces or degraded I-Sn and OSP (Organic Surface Protection) can be soldered with the aid of halogenated fluxes. Halogens provide a great process window in solderability. The problem however is that the residues and reaction products of halogenated fluxes can be problematic for electronic circuits. They usually have high hygroscopicity and high water solubility and give an increased risk on electro migration and high leakage currents. This means a high risk on malfunctioning of the electronic circuit. Specifically with lead-free soldering alloys there are more reports that even the smallest levels of halogens can be problematic for sensitive electronic applications. Sensitive electronic applications are typically high resistance circuits, measuring circuits, high frequency circuits, sensors,...That's why the tendency is to move away from halogens in soldering chemistry in electronics manufacturing. In general when the solderability of the surfaces to be soldered from component and PCB (Printed Circuit Board) are normal, there is no need for these halogens. Smartly designed absolutely halogen free soldering products will provide a large enough process window to clean the surfaces and get a good soldering result and this in combination with high reliability residues.