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.
A thermal soak zone is next in the process. This soak usually lasts no longer than two minutes and is designed to remove paste volatiles and activate the flux components to begin oxide reduction on leads and pads of circuits. Again the temperature must be precise to prevent spattering or balling of solder from heat that is too high. When the soak is complete a thermal assessment of the entire board is required before it moves to the next zone.
The reflow zone is also called the time above liquidus or TAL. This is the point where the highest temperature is reached. This is a very important component because it must not surpass the highest temperature that can be tolerated by the part most sensitive to thermal damage. The process takes approximately one minute and should be closely monitored to ensure the temperatures do not surpass the limit set for the piece.
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.
A thermal soak zone is next in the process. This soak usually lasts no longer than two minutes and is designed to remove paste volatiles and activate the flux components to begin oxide reduction on leads and pads of circuits. Again the temperature must be precise to prevent spattering or balling of solder from heat that is too high. When the soak is complete a thermal assessment of the entire board is required before it moves to the next zone.
The reflow zone is also called the time above liquidus or TAL. This is the point where the highest temperature is reached. This is a very important component because it must not surpass the highest temperature that can be tolerated by the part most sensitive to thermal damage. The process takes approximately one minute and should be closely monitored to ensure the temperatures do not surpass the limit set for the piece.
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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