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.
The oven should be able to heat the adjoining surface melting all the solder into their correct positions without overheating or damaging the electrical components. One or more ceramic infrared heater are used as the source of heat that is then directed to heat the assemblies through radiation process although some ovens(Infrared types) uses fans to direct heat to the assemblies.
A basic reflow oven has four stages through which the operation goes to be complete. The starting point is the preheat zone. This is where the temperature/time rate (ramp rate) is determined. It is the rate at which the temperature of the mounting board and the electrical components on it changes relative to time. This is significant as it helps determine the maximum temperatures possible that can be reached and for how long. The solvent in the mix also starts evaporating at this point.
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.
Maximum temperatures are reached at the reflow zone (the third stage). At this stage, the surface tension of the flux gets reduced at the metal juncture resulting to metallurgical bonding-all the solder powder combines. In considering the maximum tolerable temperature, the components with the lowest thermal damage is very significant as the maximum operating temperature is set slightly below this level. It is at this phase that full control of the temperatures and exposure time must be done for obvious reasons of avoiding device destruction.
The last stage is the cooling zone where the circuit board and its component are cooled. This process too is done under efficient temperature control as sudden temperature changes may result to thermal shock. It is also important to avoid excessive metallic formation at this stage as the desired finished circuit board should have components attached with fined grained structured solder making it mechanically sound.
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 business environment around us is rapidly changing particularly in regards to the customers, market, technology and competition hence the need to continuously review or operating methods to be sure they are optimal. The best reflow soldering oven guarantees maximum productivity and profitability for assembly firms and other businesses require soldering.
The oven should be able to heat the adjoining surface melting all the solder into their correct positions without overheating or damaging the electrical components. One or more ceramic infrared heater are used as the source of heat that is then directed to heat the assemblies through radiation process although some ovens(Infrared types) uses fans to direct heat to the assemblies.
A basic reflow oven has four stages through which the operation goes to be complete. The starting point is the preheat zone. This is where the temperature/time rate (ramp rate) is determined. It is the rate at which the temperature of the mounting board and the electrical components on it changes relative to time. This is significant as it helps determine the maximum temperatures possible that can be reached and for how long. The solvent in the mix also starts evaporating at this point.
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.
Maximum temperatures are reached at the reflow zone (the third stage). At this stage, the surface tension of the flux gets reduced at the metal juncture resulting to metallurgical bonding-all the solder powder combines. In considering the maximum tolerable temperature, the components with the lowest thermal damage is very significant as the maximum operating temperature is set slightly below this level. It is at this phase that full control of the temperatures and exposure time must be done for obvious reasons of avoiding device destruction.
The last stage is the cooling zone where the circuit board and its component are cooled. This process too is done under efficient temperature control as sudden temperature changes may result to thermal shock. It is also important to avoid excessive metallic formation at this stage as the desired finished circuit board should have components attached with fined grained structured solder making it mechanically sound.
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 business environment around us is rapidly changing particularly in regards to the customers, market, technology and competition hence the need to continuously review or operating methods to be sure they are optimal. The best reflow soldering oven guarantees maximum productivity and profitability for assembly firms and other businesses require soldering.
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