In the assembly industries, the process of attaching electronic components on to a printed circuit board (PCB) is usually done by soldering them onto the board. Reflow soldering oven is one of the most modern devices used for to achieve this attachment. The process starts with a sticky mixture of flux and powdered solder that helps to attach the components on to their correct positions on to the board. A process of controlled heating and cooling then follows to achieve permanent joints.
One or more ceramic infrared heaters can be used for heating the oven. The heat is then directed through the radiation process to the assembly compartments although infrared ovens use fans to direct heat to the assembly. The target is usually to expose PCB to the optimum heat conditions enough to melt the solder into the correct positions without damaging the PCB or devices on it.
In a conventional reflow soldering oven, there are four phases or zone with a unique thermal profile for each. It all starts in the preheat zone where the time/temperature relationship (ramp-rate) is determined. This is the rate at which the temperature changes on the PCB and it is important so that the PCB does not crack or components do not get destroyed. The solvent in the paste starts to evaporate at this phase.
The PCB is then taken to the thermal soak zone where the removal of solder paste volatiles takes place. Flux activation which involves freeing of leads and pads of any oxide then follows. The temperature range is anywhere between 60 to 120 degrees primary depending on the predetermined ramp rate.
The reflow zone is the third place where the temperatures reaches maximum peak, usually above the liquidus point. The soldering paste is molten under efficiently controlled conditions reducing the surface tension of flux at the point of metal juncture. The result of this process is the permanent fixing of electrical components on to the circuit board. The ramp rate and temperature control is highly significant at this phase. The sudden change of temperatures from the soak zone to above liquidus can easily destroy the devices through temperature shock and thus calls for very efficient control mechanisms.
Cooling takes place in the last phase also known as the cooling zone from where the molten solder solidifies into the precise target points permanently fixing the electronic components on to the PCB. The temperature control is still significant as such problems like thermal shock or the excessive metallic formation must be avoided I order to obtain a mechanically sound devices attached with fine grained structured solder.
With the modern sophisticated ovens, the most up to date technologies are employed to give the best possible yields. These are operated by modern setup processes that identify the best possible combination of zonal temperatures and conveyor speed. Among other things, the production time has been significantly minimized greatly increasing efficiency.
The changing customer needs, competition, market condition and the general technology all calls for adopting measures that optimizes operating efficiency in terms of yield and profitability. It is such measures that can ensure the survival of a firm into the future. For assembly firms in particular, an efficient and modern reflow soldering oven is more than necessary as it increases the production rate and minimizes on power consumption.
One or more ceramic infrared heaters can be used for heating the oven. The heat is then directed through the radiation process to the assembly compartments although infrared ovens use fans to direct heat to the assembly. The target is usually to expose PCB to the optimum heat conditions enough to melt the solder into the correct positions without damaging the PCB or devices on it.
In a conventional reflow soldering oven, there are four phases or zone with a unique thermal profile for each. It all starts in the preheat zone where the time/temperature relationship (ramp-rate) is determined. This is the rate at which the temperature changes on the PCB and it is important so that the PCB does not crack or components do not get destroyed. The solvent in the paste starts to evaporate at this phase.
The PCB is then taken to the thermal soak zone where the removal of solder paste volatiles takes place. Flux activation which involves freeing of leads and pads of any oxide then follows. The temperature range is anywhere between 60 to 120 degrees primary depending on the predetermined ramp rate.
The reflow zone is the third place where the temperatures reaches maximum peak, usually above the liquidus point. The soldering paste is molten under efficiently controlled conditions reducing the surface tension of flux at the point of metal juncture. The result of this process is the permanent fixing of electrical components on to the circuit board. The ramp rate and temperature control is highly significant at this phase. The sudden change of temperatures from the soak zone to above liquidus can easily destroy the devices through temperature shock and thus calls for very efficient control mechanisms.
Cooling takes place in the last phase also known as the cooling zone from where the molten solder solidifies into the precise target points permanently fixing the electronic components on to the PCB. The temperature control is still significant as such problems like thermal shock or the excessive metallic formation must be avoided I order to obtain a mechanically sound devices attached with fine grained structured solder.
With the modern sophisticated ovens, the most up to date technologies are employed to give the best possible yields. These are operated by modern setup processes that identify the best possible combination of zonal temperatures and conveyor speed. Among other things, the production time has been significantly minimized greatly increasing efficiency.
The changing customer needs, competition, market condition and the general technology all calls for adopting measures that optimizes operating efficiency in terms of yield and profitability. It is such measures that can ensure the survival of a firm into the future. For assembly firms in particular, an efficient and modern reflow soldering oven is more than necessary as it increases the production rate and minimizes on power consumption.
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