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Everything you purchase today that is electronic uses circuit boards to keep them running. How these circuit boards are made demands use of complicated specialty equipment designed specifically for making the components for tablets, smart phones and virtually every other electronic devise available. One of the machines needed to create these mobile connections and ensure they work is the reflow soldering oven.
By placing a powdered solder mixture on the circuit board manufacturers can bond two materials. The boards are heated in ovens until the solder becomes liquid and will, when cooled, permanently bind the circuits to the board. To complete the process the boards and circuits must travel through four stages of heat and cooling. These stages are called zones by the manufacturers.
The first zone is a preheat period where the boards and other components are heated to determine the ramp up rate. If the boards and circuitry heat up too fast it can cause damage to the components from thermal shock causing cracking and also spattering of solder paste. If the heating process is too low the needed evaporation of the flux in the paste will be incomplete.
The second step is called a thermal soak. In this zone the board sits for up to two minutes in the heat and works to activate flux components that starts the oxide reduction and removes the excess paste from the actual circuit ends and pads. As with all steps in this process the temperature must be exact. Too high and there will be spattering or balling of any solder being used. Before moving to the next level the boards receive a complete thermal assessment.
The third step in the process is called the reflow zone. It is also referred to as the time above liquidus or TAL and is the point of highest heat in this process. Operators must monitor the temperature closely in this zone because if it surpasses the level of heat that can be tolerated by the weakest component thermal damage will occur. The entire process lasts about a minute and the solder becomes liquid and "reflows".
The final step is the cooling zone. This is a slow process that gradually cools the board and causes the liquid solder to become solid. When done properly it can help to prevent excess thermal shock to the boards and their components. Many companies pay little attention to the cool down rate because it is less critical than the ramp up rate but a cooling rate of four degrees Celsius per second is recommended.
Most equipment used in this process allows the operator to see what is happening inside the closed unit. Some are equipped with viewing windows and others can be attached to a screen using a USB connection. This viewing allows the operator to adjust the temperatures while monitoring the progress of each board.
The importance of these ovens is seen every day in nearly every household in the country. People use electronics virtually everywhere they go whether it is to the office or school or driving down the road using a service to find your way. These ovens help provide the convenience of electronics that have become a way of life for many.
By placing a powdered solder mixture on the circuit board manufacturers can bond two materials. The boards are heated in ovens until the solder becomes liquid and will, when cooled, permanently bind the circuits to the board. To complete the process the boards and circuits must travel through four stages of heat and cooling. These stages are called zones by the manufacturers.
The first zone is a preheat period where the boards and other components are heated to determine the ramp up rate. If the boards and circuitry heat up too fast it can cause damage to the components from thermal shock causing cracking and also spattering of solder paste. If the heating process is too low the needed evaporation of the flux in the paste will be incomplete.
The second step is called a thermal soak. In this zone the board sits for up to two minutes in the heat and works to activate flux components that starts the oxide reduction and removes the excess paste from the actual circuit ends and pads. As with all steps in this process the temperature must be exact. Too high and there will be spattering or balling of any solder being used. Before moving to the next level the boards receive a complete thermal assessment.
The third step in the process is called the reflow zone. It is also referred to as the time above liquidus or TAL and is the point of highest heat in this process. Operators must monitor the temperature closely in this zone because if it surpasses the level of heat that can be tolerated by the weakest component thermal damage will occur. The entire process lasts about a minute and the solder becomes liquid and "reflows".
The final step is the cooling zone. This is a slow process that gradually cools the board and causes the liquid solder to become solid. When done properly it can help to prevent excess thermal shock to the boards and their components. Many companies pay little attention to the cool down rate because it is less critical than the ramp up rate but a cooling rate of four degrees Celsius per second is recommended.
Most equipment used in this process allows the operator to see what is happening inside the closed unit. Some are equipped with viewing windows and others can be attached to a screen using a USB connection. This viewing allows the operator to adjust the temperatures while monitoring the progress of each board.
The importance of these ovens is seen every day in nearly every household in the country. People use electronics virtually everywhere they go whether it is to the office or school or driving down the road using a service to find your way. These ovens help provide the convenience of electronics that have become a way of life for many.
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