Surface Mount Technology (SMT) is a technology of soldering electrical components onto the pre-printed circuit boards. In order to make the whole process possible, SMT reflow soldering oven is usually used. This is a machine that employs high level of technology and bonding principles in its functionality. It is very complex but offers reliability and better alternative in the field of electrical assembly. This comes with advantages such as reduced board cost, controlled manufacturing and assembling process and reduced material handling.
The reflow soldering is the process of joining electronic devices to the printed circuit boards as the contact pads. This requires the use of solder paste and heat to attach the components. It is the SMT reflow soldering oven that is best in this. It allows for better control of heating process that minimizes chances of defective components.
It all starts by making of solder paste. This is a mixture of small solder particles, flux and some solvent that also work as a cleaning agent. This forms a sticky substance that is used to loosely attach electrical components on to specific points on the circuit board.
The PCB and loosely attached components is then drawn into the heating chambers through a conveyor belt. This then undergoes into four distinct phases in this machine. The first phase is known as preheat zone. This is where the melting point of the solvent is set. The ramp rate (time/temperature rate) is also determined and used to control heating in the following stages.
The second zone is the thermal soak zone. Removal of paste volatiles takes place here through a 60 to 120 second heat exposure of the PCB at a predetermined temperature. This is followed by the reflow stage, the stage in which the whole thing happens. Printed circuit board and components are exposed to the highest possible temperatures. The tolerable (liquidus) temperature for each of the component is determined and the maximum temperature is set just below it. This forces reduction between the surface tension between solder particles so that they melt at the point of contact on the pad.
In the fourth and final zone, the process of cooling takes place. This too is a controlled process. The heating and cooling is such controlled that the PCB and components are not exposed to thermal shock. This is perhaps what makes SMT reflow soldering oven outperform all other methods of bonding.
The oven gets heated by ceramic heaters and heat transfer to the assembly points can be through radiation (hot air) or the infrared electromagnetic radiation depending on the machine make. Other technologies of heat transfer are also used.
These machines have gained favor with electronic assemblers for various reasons. These include simple methods of operating, faster production, high level of accuracy, produces much more component per unit time than any other method. In addition to this, depending on the model, it is possible to attach the components on both sides of PCB and there is efficiency in electricity utilization.
Electronic assembly just like any other industry is highly competitive. In order to remain a relevant market player, a firm must acquire the latest technology and most efficient production methods. The use of SMT reflow soldering oven is no longer optional in electrical assembly. In addition to higher level of production, efficiency and lower power consumption, the machine guarantees firms future survival and profitability.
The reflow soldering is the process of joining electronic devices to the printed circuit boards as the contact pads. This requires the use of solder paste and heat to attach the components. It is the SMT reflow soldering oven that is best in this. It allows for better control of heating process that minimizes chances of defective components.
It all starts by making of solder paste. This is a mixture of small solder particles, flux and some solvent that also work as a cleaning agent. This forms a sticky substance that is used to loosely attach electrical components on to specific points on the circuit board.
The PCB and loosely attached components is then drawn into the heating chambers through a conveyor belt. This then undergoes into four distinct phases in this machine. The first phase is known as preheat zone. This is where the melting point of the solvent is set. The ramp rate (time/temperature rate) is also determined and used to control heating in the following stages.
The second zone is the thermal soak zone. Removal of paste volatiles takes place here through a 60 to 120 second heat exposure of the PCB at a predetermined temperature. This is followed by the reflow stage, the stage in which the whole thing happens. Printed circuit board and components are exposed to the highest possible temperatures. The tolerable (liquidus) temperature for each of the component is determined and the maximum temperature is set just below it. This forces reduction between the surface tension between solder particles so that they melt at the point of contact on the pad.
In the fourth and final zone, the process of cooling takes place. This too is a controlled process. The heating and cooling is such controlled that the PCB and components are not exposed to thermal shock. This is perhaps what makes SMT reflow soldering oven outperform all other methods of bonding.
The oven gets heated by ceramic heaters and heat transfer to the assembly points can be through radiation (hot air) or the infrared electromagnetic radiation depending on the machine make. Other technologies of heat transfer are also used.
These machines have gained favor with electronic assemblers for various reasons. These include simple methods of operating, faster production, high level of accuracy, produces much more component per unit time than any other method. In addition to this, depending on the model, it is possible to attach the components on both sides of PCB and there is efficiency in electricity utilization.
Electronic assembly just like any other industry is highly competitive. In order to remain a relevant market player, a firm must acquire the latest technology and most efficient production methods. The use of SMT reflow soldering oven is no longer optional in electrical assembly. In addition to higher level of production, efficiency and lower power consumption, the machine guarantees firms future survival and profitability.
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