![]() The convection types are further subdivided into three classifications: radiant dominant (Class 1 IR), a combination of convection and IR dominant (Class II IR), and convection dominant (Class III). ![]() There are three types of commonly used production soldering stations: wave solder, convection and vapor phase reflow (VPR). As a result, the thermal stress applied to the packages is minimal. As a result of the above features, the heating conditions can be kept low and the processing times can be short.Since soldering is performed in an inert atmosphere, there is minimal oxidation or contamination of the soldered sections.Since the latent heat of vaporation is used, the temperature can be controlled precisely.The efficiency with which heat is transmitted to the work is extremely high and the whole work is heated evenly regardless of the shapes of the components.Vapor phase soldering has the following characteristics. This equipment consists of the first vapor phase used for the batch reflow soldering, a preheater, cooling, and a second vapor phase to prevent splashing of the liquid from the first vapor phase. This results in highly efficient and even soldering of the product.įigure 1 shows the structure of the equipment used in this method. And it allows lower temperature processing than infrared or hot air processing.Īs mentioned above, in this method, a special inert liquid is heated by a heater and the product to be soldered is immersed in the saturated vapor atmosphere acquired by the boiling of that liquid, and the vapor that contacts the product releases its latent heat of vaporation as it condenses. Component temperature never exceeds the vapor temperature in a vapor phase system-a significant benefit for complex board architectures and low-mass, heat - sensitive devices, including surface mount technology. Vapor phase soldering offers a higher rate of heat transfer than other reflow heating modes, conducting energy uniformly without dependence on circuit assembly mass, geometry, color or composition. High reliability soldering minimizes the high cost and delay of defective board rework. This heating mode has been adapted to mass reflow soldering, paint and polymer coating and polymer fusing, where it provides precise temperature control in a clean, non-oxidizing and non-flammable environment. Heat is transferred when the hot, saturated vapor condenses on a surface and gives up its latent heat of vaporization. Vapor phase or condensation heating is a direct contact process that takes place in a zone of heated, saturated vapor.
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