The performance of any electronic gadgets depends on the segments utilized as well as how well they are appended to their contact pad. Given the exactness with which the parts must be connected, special machines are required to perform this fragile task. The machines that are always present in any genuine electronic assembling company are the smt reflow ovens.
The ovens are designed to assist in the process of reflow soldering; the technique whereby some sticky soldering paste made of solder and flux is used to temporarily attach electrical components to the contact pads. This is then followed by highly controlled heating aiming to melt the solder so as to permanently connect the components to the circuit board.
Thanks to this oven, surface mount (smt) components can be attached to the circuit board in a matter of minutes eliminating several labor hours that are necessary if other methods like individual joint soldering is used. The oven is specifically designed to be able to heat the surface melting the solder without damaging any of the electrical components. The typical reflow oven consists of four distinctive stages; preheat, the thermal soak, the reflow and the cooling zone.
In the preheat zone, the ramp-rate is established. This is the rate of temperature increase per second. It is usually 1 to 3 degrees per second. It must not exceed the maximum slope as this can cause thermal shock damaging components or cracking the mother board in the process. It can also lead to the spattering effect. The solvent in the paste also starts to evaporate in this zone.
This is followed by the thermal soak zone lasting for 60 to 120 seconds allowing for the removal of solder paste volatiles. The flux components also begin the process of oxidation of the component pads and leads, a process known as flux activation. The temperature must be right, with low temperatures, flux fails to fully activate while high temperatures causes spattering, balling or paste oxidation or even contamination of components.
The reflow zone then takes over. In this zone, the highest possible temperature as determined by the component with the lowest temperature tolerance in the assembly is reached. The common peak is usually from 20 to 40 degree centigrade above liquidus.
Ultimately, the cooling zone is the last step. It is utilized to cool the prepared board in a controlled way setting all joints as required. In a proper manner, this stage should prevent any intermetallic formation or even the thermal shock. Faster cooling is however done to so as to accomplish fine grains. All in all, there is a need for efficient control system, something possible with most of the modern designs.
If the company intends to improve the efficiency of their production, it pays to buy a new reflow oven. They can be ordered online sometimes with very favorable discounts. The online orders should be done with a lot of care and caution. It is appropriate to fast carry out due diligence, go through the website of the sellers, gather all the information about the specific model to be purchased and talk to customers who have experience dealing with the store. This ensures that the company does not fall prey to substandard products or fraudulent deals as a whole.
The ovens are designed to assist in the process of reflow soldering; the technique whereby some sticky soldering paste made of solder and flux is used to temporarily attach electrical components to the contact pads. This is then followed by highly controlled heating aiming to melt the solder so as to permanently connect the components to the circuit board.
Thanks to this oven, surface mount (smt) components can be attached to the circuit board in a matter of minutes eliminating several labor hours that are necessary if other methods like individual joint soldering is used. The oven is specifically designed to be able to heat the surface melting the solder without damaging any of the electrical components. The typical reflow oven consists of four distinctive stages; preheat, the thermal soak, the reflow and the cooling zone.
In the preheat zone, the ramp-rate is established. This is the rate of temperature increase per second. It is usually 1 to 3 degrees per second. It must not exceed the maximum slope as this can cause thermal shock damaging components or cracking the mother board in the process. It can also lead to the spattering effect. The solvent in the paste also starts to evaporate in this zone.
This is followed by the thermal soak zone lasting for 60 to 120 seconds allowing for the removal of solder paste volatiles. The flux components also begin the process of oxidation of the component pads and leads, a process known as flux activation. The temperature must be right, with low temperatures, flux fails to fully activate while high temperatures causes spattering, balling or paste oxidation or even contamination of components.
The reflow zone then takes over. In this zone, the highest possible temperature as determined by the component with the lowest temperature tolerance in the assembly is reached. The common peak is usually from 20 to 40 degree centigrade above liquidus.
Ultimately, the cooling zone is the last step. It is utilized to cool the prepared board in a controlled way setting all joints as required. In a proper manner, this stage should prevent any intermetallic formation or even the thermal shock. Faster cooling is however done to so as to accomplish fine grains. All in all, there is a need for efficient control system, something possible with most of the modern designs.
If the company intends to improve the efficiency of their production, it pays to buy a new reflow oven. They can be ordered online sometimes with very favorable discounts. The online orders should be done with a lot of care and caution. It is appropriate to fast carry out due diligence, go through the website of the sellers, gather all the information about the specific model to be purchased and talk to customers who have experience dealing with the store. This ensures that the company does not fall prey to substandard products or fraudulent deals as a whole.
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