SMT chip processing what are the requirements and precautions?

With the development of miniaturization of electronic products, the size of SMD components is also getting smaller and smaller. The requirements of high-sensitive components on the processing environment are also getting higher, putting higher demands on SMT chip processing. As a well-run and well-controlled SMT chip factory, in addition to strictly controlling the process flow, we must strictly control the environment of the SMT workshop and clearly understand some precautions.

First, SMT chip processing plant environmental requirements

SMT production equipment is a high-precision mechanical and electrical integration of equipment, equipment and process materials on the environment cleanliness, humidity, temperature has certain requirements. To ensure the normal operation of equipment, reduce environmental damage to components, improve quality, SMT workshop environment has the following requirements:

1, power

Generally require single-phase AC220 (220 ± 10%, 0 / 60Hz), three-phase AC380 (380 ± 10%, 50 / 60Hz), the power of the power to more than double the power consumption.

2, gas source

According to the requirements of the equipment to configure the pressure of the gas source, you can use the factory gas source, you can also configure a separate oil-free compressed air machine, the general pressure greater than 7kg / cm2. Requires clean, dry clean air, so the need for compressed air to oil, dust, water treatment. Air pipes are made of stainless steel or pressure-resistant plastic tubing.

3, exhaust

Reflow and wave soldering equipment need to configure the exhaust fan. For all hot blast stoves, the minimum flow rate for the exhaust air duct is 500 CFM (14.15 m3 / min)

4, temperature and humidity

The workshop temperature is 23 ± 3 ℃, generally 17 ~ 28 ℃, relative humidity 45% ~ 70% RH.According to the size of the workshop to set the appropriate temperature and humidity meter, timing monitoring, and is equipped with temperature and humidity control Facilities.

5, anti-static

Staff need to wear anti-static clothing, shoes, anti-static bracelet to enter the workshop, anti-static work area should be equipped with anti-static ground, anti-static seat cushion, anti-static bags, crates,

Second, SMT chip processing considerations

1, solder paste refrigeration

Paste just bought back, if not immediately use, need to be refrigerated in the refrigerator, the temperature at 5 ℃ -10 ℃, not less than 0 ℃. SMT chip processing manufacturers on the use of paste mixing, there are many online explanations, not much introduction here.

2, timely replacement of Mounter easy loss of goods

In the placement process, due to the aging of the placement machine equipment and nozzle, feeder damage, easily lead to the placement machine crooked, and the high thrown material, reducing production efficiency and increase production costs. In the case of equipment can not patch machine, you should carefully check the nozzle is blocked, damaged, and the feeder is intact.

3, test the temperature

PCB welding quality is good or bad, and reflow process parameters set has a great relationship. In general, the day needs to be twice the furnace temperature test, the lowest one day to test again to continuously improve the temperature curve, set the temperature curve fit welding products. Do not miss out on this link for the sake of your productivity and cost savings.