PCB shelf life is how long? And how to determine the baking temperature?
Update Time ： 2017-05-03 View ： 4177
PCB after the completion of the manufacturing, there is a shelf life, more than the shelf life of the need for PCB baking, otherwise easy to make the PCB in the SMT line production, the issue of PCB burst plate.
PCB save time, as well as the use of industrial oven baked PCB temperature and time are the industry norms.
PCB shelf life is how long? And how to determine the baking temperature?
A, PCB control norms
1, PCB unpacking and storage
(1) PCB board sealed unopened manufacturing date within 2 months can be directly used on-line
(2) PCB board manufacturing date within 2 months after unpacking unpacking date must be labeled
(3) PCB board manufacturing date within 2 months after unpacking must be within 5 days on the line after use
2, PCB baking
(1) PCB in the manufacture date within 2 months of sealing opened more than 5 days, please take 120 - 5 DEG C baking for 1 hours
(2) PCB for more than 2 months before the date of manufacture, before the line, please bake at 120 + 5 DEG C for 1 hours
(3) if PCB exceeds the manufacturing date from 2 to 6 months, please bake for about 120 ~ 5 DEG C on the line for 2 hours
(4) if PCB exceeds the manufacturing date for 6 months to 1 years, please bake for about 120 ~ 5 DEG C on the line for about 4 hours
(5) baked PCB must be used within 5 days (IR REFLOW), the use of the end of the need to bake for another 1 hours before the line can be used.
(6) PCB for more than 1 years before the date of manufacture, please refer to the 120 - 5 DEG C baking 4 hours, sending the PCB factory to use on-line re spray tin
3, PCB baking method
(1) large PCB (more than 16 PORT) with a flat and put in place, a stack of up to a maximum of 30 pieces, baking finished within 10 minutes to open the oven to remove the PCB PORT natural cooling (need to press the anti plate Bay fixture)
(2) small and medium PCB (8PORT 8PORT) mining flat is placed, a maximum number of 40, the vertical number is not limited, baking 10 minutes to open the oven to remove PCB flat natural cooling (need to pressure plate Bay fixtures)
Two, different regions of PCB preservation, baking
PCB specific storage time and baking temperature, not only with the PCB manufacturer's production capacity and production process, but also has a great relationship with the region.
OSP process and pure gold deposition process of PCB, generally in the shelf life of 6 months after the packaging, OSP process is generally not recommended for baking.
Have a great relationship with the preservation of PCB and curing time in the southern region, the general moisture is relatively heavy, especially in the areas of Guangdong and Guangxi, in March and April of each year there will be back to the south of the rainy weather, every day, it is very damp. PCB exposure in the air must be used up within 24 hours, otherwise easy to oxidation, after the normal Kaifeng, the use of 8 hours is the best. For some PCB that need to be baked, the baking time is longer. In the northern region, the weather is generally more dry, PCB preservation of the president some time, baking time can be shorter. The baking temperature is generally 120 ~ 5 DEG C baking, baking time according to the specific circumstances to decide.
For the preservation of PCB time, baking time and temperature, to analyze specific issues, based on PCB control standard, according to the different manufacturers of the production capacity, technology, regional and seasonal, specific choice.
