The PCB manufacturing assembly reflow oven is a device for soldering PCB mounting components. PCB manufacturing reflow furnaces mainly include infrared furnaces, hot air furnaces, infrared heating furnaces, steam welding furnaces, etc. The most popular ones are forced full hot air furnaces. This section mainly introduces the forced full hot blast stove.
First, the classification of PCB manufacturing reflow soldering furnace
There are many types of PCB manufacturing reflow soldering furnaces, according to the chip processing and reflow soldering heat area, it can be divided into two categories: the overall heating of the PCB circuit board and the rejection heating of the PCb prototype circuit board.
Second, the full hot air reflow soldering furnace is currently the most widely used reflow soldering furnace, the main body consists of furnace body, upper and lower heating source, PCB assembly transmission device, air circulation decoration, cooling device, exhaust device, temperature control device, nitrogen device , the exhaust gas recovery device and the computer control system .
1, air flow design
There are many domestic and foreign manufacturers of PCB assembly reflow soldering equipment. Each manufacturer's airflow design is different, with vertical airflow, horizontal airflow, large return air, and small return air. Either way, high convection efficiency is required, including speed, flow, fluidity, and permeability. The airflow should have good coverage. If the airflow is too large or too small, it is not good.
The figure shows the air flow design. Air or nitrogen enters the furnace from the inlet of the fan. After being heated by the heater, the heat of the hot air is transferred to the PCB assembly board by the top forced hot air generator. The cooled hot air flows through the channel and Export to outlet. Hot air reflow is a process in which hot air circulates continuously in the direction of the designed airflow to generate heat exchange with the heated devices.