Reflow ovens are used during the assembly process to bond electrical components to the PCB, printed circuit board. During the process solder paste with flux is used to achieve bonding. The perfect balance of heating the solder paste is needed to ensure success. When the temperature is too high, the PCB or the components could be damaged, yet the temperature must be high enough for the bonding to occur. These soldering ovens can now be purchased in a desktop version, the desktop reflow oven.
This particular technology is called surface mount technology, or SMT. Sometimes these ovens are called pick and place machines. The floor models of reflow ovens are very expensive and take up a certain amount of floor space. The desktop versions allow for production of small pieces in small places.
The process is very scientific and really quite amazing. Most of the computerized electronic equipment you use every day was in part manufactured in this manner. As you can imagine, the manufacturing of an electronic device with a PCB is a very precise process that includes the use of robotic technologies such as SMT.
There are four stages that take place in the reflow oven to achieve the end result of the components being securely soldered onto the PCB. These stages, or zones, are the preheat zone, thermal soak, reflow and cooling zone. During the preheat stage there is heat measurement called the maximum slope. As the preheating temperature rises in 1 to 3 degree C increments the oven must determine the maximum slope, the rate at which the heat can increase without damaging the components or evaporating the flux that is part of the soldering paste.
The thermal soak zone is brief, typically only one to two minutes. This stage activates the flux, which is the chemical cleaning agent in the solder paste. The activation of the flux causes oxide reduction on the various component pads and leads. Again, precision is needed to attain the exact temperature. At the end of this zone there should be thermal equilibrium before going into the next zone.
The reflow zone is where the machine got its name. Peak temperature is reached during this phase. It is critical that the highest temperature be 5 degrees C less than the component with the least tolerance for heat. The solder paste at this point is liquid and actually reflows through points of the assembly. This is when metallurgical bonding occurs and the components are successfully bonded to the PCB.
The fourth stage is the cooling zone. During this process the entire assembly cools and the solder joints become solid. During the third stage the oven is at it peak heat. During this final stage everything begins to cool at approximately 4 degrees C each second. After this stage, the whole assembly is ready to move to the next step in the production line.
There are several manufacturers of these soldering ovens. Some people in the market for a desktop model may already have sufficient knowledge of this equipment to make an informed choice. If you do not have the knowledge, talk to other professionals for advice and research at least three different brands before making your purchase.
This particular technology is called surface mount technology, or SMT. Sometimes these ovens are called pick and place machines. The floor models of reflow ovens are very expensive and take up a certain amount of floor space. The desktop versions allow for production of small pieces in small places.
The process is very scientific and really quite amazing. Most of the computerized electronic equipment you use every day was in part manufactured in this manner. As you can imagine, the manufacturing of an electronic device with a PCB is a very precise process that includes the use of robotic technologies such as SMT.
There are four stages that take place in the reflow oven to achieve the end result of the components being securely soldered onto the PCB. These stages, or zones, are the preheat zone, thermal soak, reflow and cooling zone. During the preheat stage there is heat measurement called the maximum slope. As the preheating temperature rises in 1 to 3 degree C increments the oven must determine the maximum slope, the rate at which the heat can increase without damaging the components or evaporating the flux that is part of the soldering paste.
The thermal soak zone is brief, typically only one to two minutes. This stage activates the flux, which is the chemical cleaning agent in the solder paste. The activation of the flux causes oxide reduction on the various component pads and leads. Again, precision is needed to attain the exact temperature. At the end of this zone there should be thermal equilibrium before going into the next zone.
The reflow zone is where the machine got its name. Peak temperature is reached during this phase. It is critical that the highest temperature be 5 degrees C less than the component with the least tolerance for heat. The solder paste at this point is liquid and actually reflows through points of the assembly. This is when metallurgical bonding occurs and the components are successfully bonded to the PCB.
The fourth stage is the cooling zone. During this process the entire assembly cools and the solder joints become solid. During the third stage the oven is at it peak heat. During this final stage everything begins to cool at approximately 4 degrees C each second. After this stage, the whole assembly is ready to move to the next step in the production line.
There are several manufacturers of these soldering ovens. Some people in the market for a desktop model may already have sufficient knowledge of this equipment to make an informed choice. If you do not have the knowledge, talk to other professionals for advice and research at least three different brands before making your purchase.
About the Author:
If you are looking for the facts regarding a desktop reflow oven, go to the web pages online here today. Additional details are available at http://www.sikama.com now.
Tidak ada komentar:
Posting Komentar