During Vapor Phase Heating (VPH), parts are directly immersed in a heated vapor blanket. The saturated vapor condenses and transfers its latent heat of vaporization to the surface of the parts. VPH, also called condensation heating, is therefore a very versatile method of heat transfer.
Galden perfluoropolyether (PFPE) fluids are available with boiling points from 165°C to 265°C and are adaptable for applications such as:
- Polymer Thick Films
- Solder Mask
- Conductive Inks
Benefits of Vapor Phase
Vapor phase soldering provides an innovative method for SMT, which the following will illustrate: At atmospheric pressure the temperature of the vapor will be the same as that of the boiling liquid. Fluctuations in temperature are much less than if infrared or laser heat is used because even if power is increased, the rate of vapor production will increase but the temperature remains the same. Galden PFPE primary VPS fluids are available in a wide temperature range, for example from LS/155 to HS/260 (155°C and 260°C boiling points respectively).
The vapor density of Galden PFPE fluids is much higher than that of air and therefore soldering takes place in an inert atmosphere, thereby removing the added cost incurred from the use of inert gases such as nitrogen.
The process is extremely fast and efficient since the heat transfer coefficient of vapor condensation is about ten times (10x) faster than hot air and about eight times (8x) faster than infra red heat.
VPR is independent of size, shape or geometry with the maximum surface area exposed and every component part seeing precisely the same temperature.
The process is clean as the components only come in contact with distilled vapors. Furthermore, the inertness of Galden fluid does not present a compatibility problem with these components. Also because of their low heat of vaporization, Galden fluids evaporate quickly from the hot surface resulting in rapid, residue free drying of the parts. Galden fluids exhibit high chemical and thermal