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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 is one of the machines that get used more often than any other machines in the electrical line of assembly. Before passing over to the oven, the solder paste made of flux, small solder particles and chemical cleaning agents is used to loosely attach the electrical components on to the printed circuit board (PCB) and then sent to the next step.
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.
Through a conveyor belt, the PCB and the mounted components are directed into the oven. This requires time and temperature precision to avoid destroying any of the components. There are four phases that these components pass through in the oven. In starts at preheat zone where time/temperature rate (ramp rate) is determined. This is important to the other zones too as it gives the correct temperature to be used. The melting point of solvent is also set here.
This is followed by thermal soak zone where the PCB and its components are exposed to heating at specific temperature for between 60 to 120 seconds to remove paste volatiles. The third stage is reflow zone. At this stage, PCB gets exposed to the maximum possible temperature that is tolerable by all the electronics on it. This is usually set below the liquidus temperature-the temperature above which the electronics get destroyed. At this point, the surface tension at the joints and the joints is reduced, melting the solder and as such bonding the pads and electronics.
The cooling zone is the last phase where controlled cooling is done to avoid thermal shock. This result of this is permanent bonding of the electrical components to PCB ready for use in electronic market after cleaning and testing.
Most of these ovens use ceramic heaters as the source of heat. The heat flows to the assemblies through hot air using fan (radiation) or just the infrared electromagnetic radiation. As the new models are introduces, the techniques of heat transfers are improved.
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.
The revolution in technology has seen production of better SMT reflow soldering ovens with the latest ones being very efficient in energy consumption, capable of large volume of production thus reducing assembly and handling time and with better quality finished products which all translates to higher profits for the firm and better and safer electronics.
This is one of the machines that get used more often than any other machines in the electrical line of assembly. Before passing over to the oven, the solder paste made of flux, small solder particles and chemical cleaning agents is used to loosely attach the electrical components on to the printed circuit board (PCB) and then sent to the next step.
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.
Through a conveyor belt, the PCB and the mounted components are directed into the oven. This requires time and temperature precision to avoid destroying any of the components. There are four phases that these components pass through in the oven. In starts at preheat zone where time/temperature rate (ramp rate) is determined. This is important to the other zones too as it gives the correct temperature to be used. The melting point of solvent is also set here.
This is followed by thermal soak zone where the PCB and its components are exposed to heating at specific temperature for between 60 to 120 seconds to remove paste volatiles. The third stage is reflow zone. At this stage, PCB gets exposed to the maximum possible temperature that is tolerable by all the electronics on it. This is usually set below the liquidus temperature-the temperature above which the electronics get destroyed. At this point, the surface tension at the joints and the joints is reduced, melting the solder and as such bonding the pads and electronics.
The cooling zone is the last phase where controlled cooling is done to avoid thermal shock. This result of this is permanent bonding of the electrical components to PCB ready for use in electronic market after cleaning and testing.
Most of these ovens use ceramic heaters as the source of heat. The heat flows to the assemblies through hot air using fan (radiation) or just the infrared electromagnetic radiation. As the new models are introduces, the techniques of heat transfers are improved.
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.
The revolution in technology has seen production of better SMT reflow soldering ovens with the latest ones being very efficient in energy consumption, capable of large volume of production thus reducing assembly and handling time and with better quality finished products which all translates to higher profits for the firm and better and safer electronics.
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Prospective customers can find industrial smt reflow soldering oven from www.sikama.com. Order directly from us by using this link http://www.sikama.com and see how much you will save today!
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