graeme herlihy, engel uk, mucell process
TRANSCRIPT
Introduction to MuCell®
Graeme HerlihyManaging Director – Engel UK
MuCell® equipment | insert gas into the melt
MuCell® barrel + MuCell® Interface Kit
MuCell® Gas dosing unit
Gas distribution
Why foaming of thermoplastics?
• lighter
• more accurate
• more economic
MuCell® | foaming of thermoplastics
• Foming agent
- N2 or CO2
• “Internal“ homogenous post-pressure
- no sink marks
- minimized warpage
- weight saving
- clamp force reduction
• Viscosity lowering
- due to physical foaming agent
- optimised filling of cavity –
new mould and filling strategies possible
MuCell® | foaming of thermoplastics
Strategic benefit | capacity use
MuCell® | reduced cycle time
Source: Trexel
Reduced cooling time
More exchange,
Less temperature
Hold time (nearly)eliminated
ΔT
Solid
MuCell®
Pack&Hold CoolingInjectionOpening/Eject./Closing
ΔT depends onmaterial type,part design andmould cooling
Cycle time reduction | optimized cooling is the key
Hot spots | optimized cooling system required
hot spots – optimised cooling system required
MuCell® | clamp force reduction
Strategic benefit | lower tonnage
• Reduced filling pressure
• No “external” holding pressure
Surface quality | surface defects
streaks on part surface
Optimazation |
• special material grades
• higher injection speed
• variotherm mould heating
• IML
• gas counter pressure
• coinjection (core foammelt - skin compact)
• …
Filling process | creation of streaks
MuCell® | applications
• volumetrically filling of the cavity
• increasing the cavity
- by clamp unit or by mould internally
• foaming inside the cavity
MuCell® + decompression stroke | function
part
thickness
time
platen
screw
mould closed
serial precision opening(parallelism controlled)stroke
MuCell® + decompression stroke | advantages
• low density achievable
• higher bending stiffnessat same part weight
• equal cell structures
• insulation effect
plate PP T20
- starting wall thickness 3 mm
- final wall thickness 10 mm
half shell PP T20- starting wall thickness 8 mm- final wall thickness 16 mm
Introduction to MuCell®
Graeme HerlihyManaging Director – Engel UK