Bridge breaker
Vol. 22 #2, Sept. 1995
The usual cure for a bridged screw, where some polymer has melted onto the screw root and impedes the solids conveying action, is to pull the screw for cleaning. It is sometimes possible to clear the blockage without pulling the screw by pushing a solid polymer rod down into the feed throat as the screw is turning, allowing the screw to bite off large sections of the rod. These large polymer pieces will sometimes provide sufficient wiping action to clean the screw root.
Always use long sections of rod to keep your hands far away from the turning screw. If you don't have a solid rod available, try some of the HDPE or PP flexible pneumatic tubing that is available in most maintenance shops.
See also
Feed throat configuration
Purge
Purge compound
Screw cleaning 2