Material Drying
10 visualizações
PA66 moisture absorption expansion dimensions
Fenómeno do problema
Precision fitting parts swell in size after a period of use in humid environment, and assembly seizes
Análise das causas
PA66 equilibrium water absorption of 2.5% brings 0.5-1% dimensional expansion, while rigidity decreases by 50-60%; precision parts used in wet environments will inevitably lose fit if moisture absorption allowance is not reserved
Solução
①Reserve moisture absorption expansion allowance in the design of precision parts for wet environments; ②Moisture condition after molding to pre-stabilize dimensions before assembly; ③Evaluate switching to low water absorption PA12 for demanding scenarios; after adjustment, take continuous samples to verify the effect, confirm stability before resuming mass production
Conclusão principal
PA66 dimension management must account the water absorption into tolerances; moisture conditioning pretreatment is a necessary process, and high-precision wet-environment parts should consider material upgrade; after confirming effectiveness, fix the parameters and practices into the work instructions to prevent recurrence
Isto foi útil?
0 pessoas acharam isto útil
Obrigado pelo seu comentário!