1. The PTFE membrane peel off. ---The PTFE membrane peel off caused by the over heating ( Partial temp >330 ℃ will cause the peel of the PTFE membrane)
2.The embrittlement of the fiberglass cloth--As we know the fiberglass cloth can working under 260℃ the instant temp can be 280℃. Only the high temp >300℃ will cause the Embrittlement of filter cloth