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Dear all,
I am doing a survey on the double sided assembly. Please take a few
minutes to complete the following questions. I will be grateful to inform
you the result once I have finished compiling.
If you have filled this before, please ignore it.
Would you care to reply, please email to [log in to unmask]
Thank you very much.
Best regards,
Victor
TN3-------------------------------------------------------
Questionaire for double sided reflow soldering
==============================================
Type of oven used : ( ) IR conventional
( x ) Forced Air
( ) Forced Air with Nitrogen
( ) Others, pls. specify _____________
Brand Name of the oven : __HELLER____________________
How often does your shop floor perform double sided reflow process?
( ) 75 % of the time, or above
( ) 50 < x < 75 % of the time
( ) 25 < x < 50 % of the time
( X ) less than 25 % of the time
What is the length of the PCB commonly used in double sided reflow process?
( X ) 200 mm or above
( ) 100 < x < 200 mm
( ) 100 mm or less
Which connecting medium do you use in the double sided reflow process?
( ) conductive adhesive + solder paste (melting pt. 183 C)
( X ) the same kind of solder paste
( ) high temp. solder paste + solder paste (melting pt. 183 C)
( ) low temp. solder paste + solder paste (melting pt. 183 C)
( ) Others : ____________________________________________________
____________________________________________________
Do you find this process difficult to control? Why? NO BUT IT SHOULD PAY
ATTENTION TO THE HEAT PROFILE ,WHICH HAS A BIG DEPENDENCE ON THE CHIP'S
DIMENTIONS._________________________________________________________________
________
____________________________________________________________________________
____________________________________________________________________________
When doing the second pass, how often did the components on the bottom side
fall off?
( X ) 1. Never happen
( ) 2. 0 < x < 20% of the time
( ) 3. 20< x < 40% of the time
( ) 4. 40< x < 60% of the time
( ) 5. 60< x < 80% of the time
( ) 6. 80% or above
If you answer 2. to 6. please list the components which caused problems :
( ) BGA, # of pins : _____ Size: _____ mm x _____ mm
( ) PLCC # of pins : _____ Size: _____ mm x _____ mm
( ) QFP # of pins : _____ Size: _____ mm x _____ mm
( ) Others(Pls. specify) : Type _______ # of pins _____ Size: ____mm x ____mm
: Type _______ # of pins _____ Size: ____mm x ____mm
What might be the suspected reasons for the fallen components? __RATIO OF
THE WEIGHT AND THE NUMBER OF LEADS
________________________________________________________________________
__________________________________________________________________________
__________________________________________________________________________
Thank you very much for your time.
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