Associated Press Writer CAIROâEgypt displayed on Monday newly discovered tombs more than 4,000 years old and said they belonged to people who worked on the Great Pyramids of Giza, presenting the discovery as more evidence that slaves did not build the ancient monuments.
Wave soldering is used for both through-hole printed circuit assemblies, and surface mount.In the latter case, the components are glued onto the surface of a printed circuit board (PCB) by placement equipment, before being run through the molten solder wave.lux in the wave soldering process has a primary and a secondary objective. The primary objective is to clean the components that are to be soldered, principally any oxide layers that may have formed. There are two types of flux, corrosive and noncorrosive.
In the case of soldering process, flux works in two ways cleaning using some chemical reaction they removes oxides from metal surface and this way improves wetting with melted solder. In high temperature metal joining processes (welding, brazing and soldering), the primary purpose of flux is to prevent oxidation base filler materials 27 jul 2013.