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At this year’s tooling for
extrusion, new processes to put wood flour into plastic were virtually
everywhere—several even start with undried flour. There was also lots of
news at the show in downstream cooling and handling of wood-filled profiles,
including the first nitrogen cooling tank. Related words are design of rigid
pvc profile, plastic, bimetallic in pvc, catheter, molding head, western
There were also plenty of technical firsts in foaming at
tooling for extrusion, specifically the
first known demonstration of foamed tooling for extrusion; the first
micro-foamed polyolefin sheet; and the deployment of a high-tech static
mixer/heat exchanger instead of a second cooling extruder for foamed PS
production.
News in blown film was somewhat less dramatic and includes the first
commercial 10-layer die, more players making side-fed dies with split resin
distribution, and advances in surface winders designed to accommodate
processor shifts to more exotic resins. A host of foreign machine builders
turned up to test the U.S. market as well.
There was loads of new process technology at
tooling
for extrusion for mixing wood with a variety of plastics. The
machine features a special venting section to draw moisture. It adds plastic
via a side mounted, single-screw extruder and uses no melt pump. Nearly a
dozen tooling for extrusion are on order to make building products
and custom profiles.
The CM92 conical counter-rotating twin-screw extruder is fed by a 140-mm
diam. twin-screw VMEDS model with a crammer auger for wood flour. The VMEDS
(Vertical Material Enhancement Delivery System, which has a vertical
integrated feed option) is preheated to 220-240 F with an electrically
heated barrel and an atmospheric vent. The preheater screw has an 8:1 L/D to
promote good distributive mixing and devolatilization, Milacron says. The
system uses no melt pump. Related words are design of rigid pvc profile,
plastic, bimetallic in pvc, catheter, molding head, western tooling
for extrusion is dried in the first four barrel sections, and
polymer is added farther downstream. After moisture is vented, the
compounding machine feeds the mixture to a 6-in., 8:1 L/D single-screw
extruder furnished by Merritt-Davis Corp., Hamden, Conn., with a new feed
section. Output is reportedly 1000 lb/hr. On the show line, the die was from
ETI–Extrusion Tooling Inc., Cummings, Ga., and downstream cooling equipment
was from ESI–Extrusion Services Inc., Akron, Ohio. W&P says it has three
wood-filled processing lines in production and several more on order.Foamed
PET
Probably a world first and certainly one of the most unusual exhibits at NPE
was a demonstration of foamed tooling for extrusion an alliance with
a commercial processor of polyolefin foams, developed an extruder with a
series of seven feeding ports for CO2- and nitrogen-based blowing agents.
Sentinel’s new process also has a specially designed, patent-pending annular
spider die. The die has a computer-controlled, pneumatic internal choke and
an internal and external die-gap adjustment system known as Autojust. The
die is designed for foamed PS, tooling for extrusion, and PP. Related
words are design of rigid pvc profile, plastic, bimetallic in pvc, catheter,
molding head, western
The foamed
tooling
for extrusion uses very high I.V. of 1.2 compared to. 0.8 for bottle
grade PET or 0.62 for recycled or fiber grade PET. The 1.2-I.V. resin is
made by only one supplier using patented solid state “poly-addition” to
raise the I.V of virgin or recycled PET. M&G now offers its high I.V. resins
in the U.S., supplied from Europe, and says that if U.S. demand grows, it
will install poly-addition equipment at its new North American plants.
tooling for extrusion earlier this year for tooling for extrusion
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