Do not force double-wall spiral together if the inner liner is catching.
Check
Look inside the joint for buckled perforated liner or bunched insulation.
Check that inner liner and outer shell are aligned before pushing.
Deburr/correct any sharp collar edges.
Use an alignment sleeve or helper support for large pieces.
Verify no insulation is exposed into the air path before sealing.
Steps
Look inside the joint for buckled perforated liner or bunched insulation.
Check that inner liner and outer shell are aligned before pushing.
Deburr/correct any sharp collar edges.
Use an alignment sleeve or helper support for large pieces.
Verify no insulation is exposed into the air path before sealing.
Say this to your foreman
The double-wall spiral at [location] caught the inner liner and packed insulation into the pipe. I pulled it back apart. Do you want this liner straightened or the section replaced before we seal it?