IPC-A-610D 10.2.7 Laminate Conditions – Bow and Twist
Acceptable - Class 1,2,3
• Bow and twist does not cause damage during post solder
assembly operations or end use. Consider ‘‘Form, Fit and
Function’’ and product reliability.
Defect - Class 1,2,3
• Bow and twists causes damage during post solder assembly
operations or end use.
Note: Bow and twist after solder should not exceed 1.5% for
through-hole and 0.75% for surface mount printed board applications
(See IPC-TM-650, 2.4.22).
具体的方法可参照IPC-TM-650, 2.4.22, 我找下稍后发给你