The general framework in the very hot air reflow soldering furnace is especially divided into five major parts: heating zone, cooling zone, fuel circulation product within the furnace, exhaust gasoline discharge machine and PCB transmission. So, the framework, theory and attributes of incredibly hot air reflow soldering? Subsequent, permit me introduce to you personally.
Structure, principle and attributes of warm air reflow soldering
Sizzling air reflow soldering composition
1. Hot air reflow soldering structure
The recent air reflow soldering furnace overall body is divided into two sealed packing containers, the upper and decrease sealed packing containers, using a conveyor belt from the middle. The size of component of the furnace overall body is mainly distinctive according to the variety of heating zone and cooling zone. The heating zone with the recent reflow furnace has 4~10 zones, the cooling zone has 1~2 zones, and several furnaces tend not to have cooling. Zone, permit the PCB board awesome the natural way from the air immediately after it's out of the oven. The temperature of every temperature zone may be set programmable. Normally, the temperature selection is usually established from room temperature to about 275 levels (as common). A further vital big difference from the reflow oven is whether or not it has the chance to accomplish nitrogen-filled soldering, or It could only be welded in an air natural environment. End users can frequently pick out the duration in the furnace human body as well as the gasoline setting specifications from the furnace in accordance with their own individual uses.
one. Heating zone composition
The composition of each heating zone during the furnace physique is identical. In each and every of the higher and decreased heating zones, a motor drives the impeller to rotate at a higher pace to generate blowing power of air or nitrogen. Immediately after the gasoline is heated by heating wires or other materials, it's blown out within the perforated plate and hits the PCB board. The motor speed of some reflow furnaces is programmable and adjustable, this kind of as Lifeng ROHS-848, which often can be from 1000~2800RPM, while some furnaces are set when leaving the manufacturing facility. By way of example, the BTU furnace factory has set a substantial pace when leaving the manufacturing facility. 3000RPM. The more quickly the motor speed, the higher the wind along with the much better the heat trade potential. By measuring the wind pressure blown via the gas, it is feasible to monitor whether or not the motor is working normally. Because of into the volatilization from the flux while in the solder paste all through the reflow procedure, it could condense on the impeller, reducing the effectiveness on the wind and leading to a reduce while in the temperature reflow profile. As a result, it is needed to examine and thoroughly clean the impeller on a regular basis.
two. Temperature command procedure
The temperature control of each and every heating zone with the sizzling air reflow soldering machine is undoubtedly an unbiased closed-loop control procedure. The temperature controller maintains the temperature at the established benefit by way of PID handle. The thermocouple wire employed by the temperature sensor is put in under the perforated plate to perception the temperature in the airflow. If your temperature of your heating zone is abnormal, these kinds of as no heating or gradual heating, it's normally necessary to examine if the sound point out relay is regular, and if the heater in the heating zone is getting older and needs to be replaced (this issue is likely to arise inside a reflow oven that's been employed for many years). If there is a temperature exhibit mistake, the thermocouple wire is mostly harmed.
3. The construction of your cooling zone
Right after the PCB board is reflow soldered, it should be cooled straight away to receive a fantastic soldering outcome. Consequently, you will find a cooling zone driving the reflow oven. The structure on the cooling zone is actually a heat exchanger with h2o circulation. Right after the cooling admirer blows the hot air to your circulating drinking water heat exchanger, the cooled air hits the PCB board. The heat during the warmth exchanger is taken away because of the circulating drinking water, along with the circulating drinking water flows again for the warmth exchanger following cooling.
In the cooling process, the flux (Flux) is a snap to condense, so it's necessary to examine and thoroughly clean the flux around the flux filter on a regular basis. Usually, the decrease of the thermal cycle performance will reduce the performance on the cooling method, make the cooling worse, and lead to the product to are unsuccessful. Welding high quality is degraded. The long-term security of overheated soldered PCB boards will lower.
Next, the theory and properties of scorching air reflow soldering
The new air reflow oven transfers warmth electricity through the laminar movement in the sizzling air. The heater and supporter are utilized to maintain the air inside the furnace heated and circulated. The areas to become welded are heated by the sizzling gasoline during the furnace to realize welding. The hot-air reflow oven has the attributes of uniform heating and steady temperature. The temperature distinction between the higher and reduce PCB along with the temperature gradient together the duration in the furnace are usually not easy to control, and it really is normally not merely used.
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