8 Failure analysis
Operating instructions GF 500
28
9.
Jointing error on the fusion surfaces
, over the entire or part of the joint
circumference due to
–
dirty and/or oxidized fusion surfaces
–
change-over time too long
–
heater temperature too high/too low
10.
Cavities in the fusion surfaces
due to
–
insufficient fusion pressure
–
cooling time too short
11.
Single, very widespread
or local concentrations of pores due to
–
soiled heating element
–
vapors formed during fusion (water/solvents)
