PCB Baking Specifications

I. The specification of PCB control

1. PCB unpacking and storage

(1) PCB board sealed and unopened can be directly used SMT assembly within 2 months of manufacturing date.

(2) The PCB board manufacturing date is within 2 months, and the unpacking date must be marked after unpacking.

(3) PCB board manufacturing date is within 2 months, after unpacking, it must be SMT assembly and used within 5 days.

2. PCB baking

(1) If the PCB is sealed and unpacked for more than 5 days within 2  months of the manufacturing date, please bake it at 120 ±5°C for 1 hour.

(2) If the PCB is more than 2 months from the manufacturing date, please bake it at 120 ±5°C for 1 hour before SMT assembly.

(3) If the PCB goes beyond 2 to 6 months of the manufacturing date, please bake it at 120 ±5°C for 2 hours before SMT assembly.

(4) If the PCB goes beyond 6 months to 1 year than the manufacturing  date, please bake it at 120 ±5°C for 4 hours before SMT assembly.

(5) The baked PCB must be used up within 5 days (put into the IR  REFLOW), and the unused PCB must be baked for another hour before being  used SMT assembly.

(6) If the PCB is more than one year from the manufacturing date, please  bake it at 120 ±5°C for 4 hours before SMT assembly, and then send it  to the PCB factory for re-spraying tin before SMT assembly.

3. PCB baking method

(1) Large-scale PCBs (≥16 PORT) are placed horizontally, and the maximum  number of a stack is 30 pieces. Open the oven within 10 minutes after  the baking is completed, take out the PCB, and let it cool naturally  (require using anti-bending fixture).
(2) Small and medium-sized PCBs (including 8PORTs below 8PORT) should be  placed horizontally, and the maximum number of a stack is 40 pieces.  The number of vertical type is unlimited. Open the oven within 10  minutes after the baking is completed, take out the PCB, and let it cool  naturally (require using anti-bending fixture).

II. The preservation and baking of PCBs in different regions

The specific storage time and baking temperature of the PCB are not only  related to the production capability and production craft of the PCB  manufacturer, but also have a great relationship with the region.

The PCB made by OSP process and immersion gold process generally has a  shelf life of 6 months after packaging, and it is generally not  recommended to bake for OSP process PCB.

The preservation and baking time of PCB has a lot to do with the region.  In the south China, humidity is generally heavier, especially in  Guangdong and Guangxi. In March and April of each year, there will be  "super humid" weather, and it is cloudy and drizzly for days on end and  very humid at this time. PCB must be used up within 24 hours when  exposed to air, otherwise it is easy to oxidize. After normal opening,  it is best to use it up in 8 hours. For some PCBs that need to be baked,  the baking time should be longer. In the northern regions of China, the  weather is generally dry, the PCB storage time will be longer, and the  baking time can also be shorter. The baking temperature is generally 120  ± 5℃, and the baking time is determined according to the specific  situation.

PCB baking oven