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.
This attaching electronics to PCB requires heating of soldering paste so that it attaches electronics on the pad on solidifying. This requires a complicated and an efficient technique, and there currently better technology to do this than an SMT reflow soldering model.
The beginning point is making of the soldering paste. This is a mixture of flux, some chemical used as cleaning agent and small solder particles. This makes a sticky paste that is used to loosely hold the electronics on to their predetermined positions on the PCB.
SMT soldering ovens are designed with specific zones, stages which numbers to a total of four. It all starts from the preheat zone. In this stage, the melting temperature of the solvent in paste is set. The time/temperature relationship also known as ramp is determined to help control heating in other zones.
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 heaters in these types of oven are made of ceramic materials with various options through which heat reaches the heating zones. The heat transfer can either be through hot air (radiation) and infrared electromagnetic radiation among other alternatives.
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.
This attaching electronics to PCB requires heating of soldering paste so that it attaches electronics on the pad on solidifying. This requires a complicated and an efficient technique, and there currently better technology to do this than an SMT reflow soldering model.
The beginning point is making of the soldering paste. This is a mixture of flux, some chemical used as cleaning agent and small solder particles. This makes a sticky paste that is used to loosely hold the electronics on to their predetermined positions on the PCB.
SMT soldering ovens are designed with specific zones, stages which numbers to a total of four. It all starts from the preheat zone. In this stage, the melting temperature of the solvent in paste is set. The time/temperature relationship also known as ramp is determined to help control heating in other zones.
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 heaters in these types of oven are made of ceramic materials with various options through which heat reaches the heating zones. The heat transfer can either be through hot air (radiation) and infrared electromagnetic radiation among other alternatives.
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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