SuZhou Tonkida Electromechanical Technology Co., Ltd Professional SMT whole line supplier

The reflow device does contain a heating circuit inside, which heats air or nitrogen to a high enough temperature to blow the board, which is already attached to the component, so that the solder on both sides of the component melts and bonds to the motherboard. This Process is not only a simple temperature Control, but also needs to ensure the overall control of equipment performance, temperature process and SPC (Statistical Process Control) to ensure welding quality.

Reflow welder

First, the basic process of reflow process adjustment

The basic process of reflow process adjustment usually includes the following key steps:

1, confirm the equipment performance:

a, hot air flow: the better range is between 4.5 ~ 6.5kl/cm²·min. Off-hour may lead to insufficient thermal compensation and decrease of heating efficiency; When it is too large, it may cause welding problems such as offset and BGA tinning. This can be optimized by adjusting the frequency of the hot air motor.

b, empty full load capacity: empty full load difference should be controlled within 3℃ to ensure temperature stability under different load conditions.

c, chain speed accuracy, stability: the chain speed deviation should be kept within 1% to ensure the consistency of the welding process.

d, track parallelism: confirm the track parallelism to prevent the phenomenon of cleats and plate drops, these problems may lead to the bottom of the board, PCB bending and tin and other defects.

e, SPC control: Implement SPC control of equipment performance, and use relevant detection tools (such as reflow process performance tester, track parallelism tester, etc.) for real-time monitoring and data analysis.

Reflow heating

2, temperature process modulation:

On the basis of confirming the stability of equipment performance, temperature process modulation is carried out. This includes adjusting the temperature Settings in each temperature zone and the speed of the transmission chain according to the recommended curve of the solder paste supplier to obtain a better furnace temperature curve parameter.

3. SPC control:

Throughout the production process, continuous SPC control is carried out to ensure the stability and consistency of welding quality. Through regular sampling test product temperature curve, and comparison analysis with standard curve, timely detection and correction of deviations.

SMT production line

Second, the technical characteristics and advantages of reflow welding

Compared with wave soldering, reflow welding has the following technical characteristics and advantages:

1. Small thermal shock: the thermal shock of components is small, which helps to protect sensitive components.

2, the amount of solder applied can be controlled: the amount of solder applied can be controlled to avoid defects such as virtual welding and continuous welding.

3, self-positioning effect: with self-positioning effect, can automatically correct small deviations of components.

4, pure solder components: solder will not be mixed with impure, to ensure the quality and reliability of welding points.

5. Flexible process: different welding processes can be used for welding on the same substrate to meet the manufacturing needs of complex electronic products.

6, high welding quality: simple process, high welding quality, help to improve the overall performance and reliability of the product.