Husky Unify - Assistance; Disassembling the Hot Runner for Fluidized Bed Cleaning

Cleaning the manifold passages is rarely required. However, if necessary, manifold passages must
be cleaned using the uidized bed process. Only the uidized bed cleaning process will
successfully remove the resin completely from the melt channels of the hot runner components.
Fluidized bed cleaning is a process with aluminum oxide particles in a high temperature retort.
The heated air at 343 to 454 °C (650 to 850 °F) levitates the aluminum oxide particles creating a
liquid-like behavior. The temperature and ow of the uidized bed pyrolizes (thermally
decomposes) the polymer.
NOTE:
Husky does not recommend using a uidized bed to clean mold plates and components.
6.15.1.1 Assistance
Husky provides a full system repair and cleaning service, in addition to helping customers
nd a
local uidized bed cleaning process.
Contact your nearest Husky Regional Service and Sales oce for more information.
6.15.1.2
Disassembling the Hot Runner for Fluidized Bed Cleaning
When disassembling a hot runner for uidized bed cleaning, do the following:
IMPORTANT!
Before disassembling a hot runner for uidized bed cleaning, please note the following:
• When removing resin from the mold, make sure the faces of the manifold are kept scratch
free. Scratches around the nozzle housing, valve bushing, manifold bushing and piston
cylinder, or sprue bushing/sprue bar surfaces may cause severe resin leakage.
• The thickness of the manifold(s) is extremely important for the performance of the hot
runner. There is a risk that cleaning the surface through grinding or sanding would change
the total height of the stack and thereby increase the cold clearance. This would result in a
resin leak.
IMPORTANT!
The uidized bed cleaning process will anneal Beryllium Copper (BeCu), causing rapid failure of
the components when returned to service.
Mechanical cleaning of BeCu components must not damage any of the sealing surfaces. Use only
soft brass, hardwood sticks, Scotch-Brite, or soft brass brushes. Do not use abrasive methods to
clean BeCu components.
v 2.2 — March 2021 Unify Manifold System
106 Assistance