Through Hole Reflow

In the pin-and-paste technology, also known as THR (= Through-Hole-Reflow) technology leaded components (THT) are soldered in the reflow process. Paste is printed into the through holes for the pins and the through-hole components are assembled on the board. During melting of the paste in the reflow system, the liquid solder is pulled, due to the wetting- and the capillary forces, into the through-holes, thus forming the solder joint. Note that because of the high thermal loads in the reflow process, the components need to be able to tolerate and withstand the high temperature.