Leistritz Corporation
Contact: Sales Manager
165 Chestnut St.
Allendale, NJ 07401
U.S.
Phone: (201) 934-8262
Fax: (201) 934-8266
Whirling Based Solutions
As the only U.S. based source of whirling equipment, Leistritz uniquely combines leadership in this innovative technology with an extensive background in traditional screw, worm, extruder and auger cutting capability. Utilized by itself, whirling offers a decisive advantage in cutting threads, screw forms, worms... anything with a pitch. When integrated with other techniques, it creates a rich spectrum of total solutions. Examples would include incorporating whirling with milling, grinding, turning as well as material handling via automated systems.
Next Twin Screw Extrusion Workshop to be held
December 1-2, 2004
Program includes presentation by 8 outside industry experts
The Leistritz Twin Screw Extrusion Workshop provides an in-depth review of twin screw
extrusion theory and practices. A unique facet of the program is that classroom training
is combined with "hands-on" operating experience. A partial list of topics is as follows:
Twin screw extruder theory and design
Screw design and process techniques
for mixing and devolatilization
Applications for co-rotation and
counterrotation
Sequencing of multi-stage process
operations
Scale-up of the twin screw extrusion
process
Feeder and materials handling for
pellets, powders and liquids Pelletizing options: strand cut, water ring,
and underwater
Direct extrusion for sheet, film, fibers
and profiles
Process considerations for reactive
extrusion
Troubleshooting twin screw extruders
and systems
Control and monitoring options
Screw assembly and disassembly
Machine maintenance
"Hands-on" demonstrations at Leistritz NJ process laboratory:
Co-rotating and counterrotating twin
screw extruders w/ up to 1200
screws rpm
Downstream addition of fillers, fibers
and additives Devolatilization of polymers
Direct sheet/film extrusion with
gear pump front end
Foam extrusion via gas injection
Outside speakers will include:
Dave Wilson, K-Tron
Chris Case, Conair/Reduction
Engineering
Adam Dreiblatt, Extrusioneering
International
Keith Luker, Randcastle Extrusion
Systems Tom Cunningham, Extrusion Technical
Services
Steve Orroth, Univ. Massachusetts at
Lowel
Rob Jerman, Fluortek
Pete Palmer, Wolock & Lott
Upcoming dates: December 1-2, 2004, and June/December 2005
Place: Classroom sessions are held at the Holiday Inn in Clinton, NJ, and machinery
demonstrations at the Leistritz Process Laboratory (10 minutes away)
Cost: $780, includes handout materials, lunches, and dinner on day 1
To register for this program contact Marion Donnelly at 908/685-2333 or e-mail
to: mhdonnelly@alec-usa.com
Acid flushing of
barrel cooling bores
Example barrels heating/cooling system
Water-cooled extruder barrels are essentially a
series of heat exchangers with coolant bores that
are subject to fouling from scale buildup. The
cooling performance of a new extruder is better than after 3 or 4 years of operation because it has smooth fresh-drilled bores. Older machines often have a layer of crusty mineral deposits lining the bores that act as an insulator.
Scale build-up leads to problems because the bores eventually become blocked. Then the only solution is to remove the barrels from the extruder and drill out the bores, which is time consuming and costly.
A simple preventive maintenance procedure is to
periodically circulate a scale removal chemical
through the bores, typically on a quarterly basis for production machines. Many chiller manufacturers supply small/inexpensive recirculating de-scaler units designed for flushing out cooling passages.
Advanced heating/cooling
technology for modular
barrel sections
Barrels for state-of-the-art twin screw
extruders are modular and typically
4 diameters in length. Heating is via
electric cartridge heaters, placed in
transverse bores in the barrel. Each
barrel section offers intensive liquid
cooling via longitudinal bores that are
close to the process melt for efficient
heat transfer.
Example of electric cartridge heaters and
cooling bores for ZSE-18 twin screw extruder Upcoming Industry Events
Color & Appearance Topcon: 9/20-21/04,
Marco Island, FL- tabletop display, presentation
by Bert Elliott entitled Tips for Optimizing Twin
Screw Extruder Performance
National Research Council of Canada's
Film/Fiber Symposium: 9/28-29/04,
Boucherville, Quebec- presentation by Stuart
Kapp entitled Twin Screw Extrusion Systems
to Manufacture Pharmaceutical
Film/Sheet/Laminates
K 2004: 10/20-27/04, Dusseldorf, Germany-
big exhibit w/ demonstrations
SPE Extrusion Minitec: 11/17/04, Charlotte,
NC-presentation by Charlie Martin entitled
Direct Extrusion from Twin Screw Extruders
American Association of Pharmaceutical
Scientist (AAPS) Annual Meeting: 11/7-11/04,
Baltimore, MD- 10 exhibit
Film & Sheet Conference: 12/8-9/04, Miami,
FL-tabletop display, presentation by Augie
Machado entitled Integrating Single & Twin
Screw Extruders for Film/Sheet Products
Heating features:
Higher wattages per barrel (particularly
beneficial for stuffing or vent barrels)
More even heating (ea. section typically
has 6 or 8 cartridges)
Fast initial warm-up time as cartridges
are internal and close to the screws
(external heaters take much longer to
heat to the core of the barrel)
A failure of even 2 or 3 cartridges does
not cause a machine shutdown Cooling features:
Closed-loop, pressurized recirculating
pump/reservoir/heat exchanger unit
Supply/return manifold headers with
solenoid valves
Micrometer flow control valves for
metering of the coolant
Check valves that prevent liquid from
entering the barrel when solenoids are
deactivated
High temperature/pressure flexible
cooling hoses to allow for thermal
expansion
FREE technical paper:
Tips for Optimizing Twin Screw Extruder Performance
By Bert Elliott, Leistritz Engineering Mgr.
A collection of 17 techniques is presented for increasing the performance of twin-screw extruders. Processors may be aware of some of
these tips, but many are not well known. All are based on solid scientific principles, and have been proven in dozens of extruder
installations. All the techniques presented are easy to apply, so the benefits can be realized quickly.
Compounding of thermoplastic materials and additives is the most common application for todays high performance ZSE-series intermeshing twin screw extruders.
Compounding of polyolefins (HDPE, LDPE, LLDPE, PP)
Compounding of Polystyrenes and Polystyrene Copolymers (e.g. ABS)
Compounding of Engineering Thermoplastics (PA, PET, PBT, PC, ABS, POM,
PMMA, PPO, PPS, PTFE, LCP, PEEK, etc.)
Compounding of heat & shear sensitive materials (XLPE, thermoplastic rubber, foamed polymers etc.)
Compounding of Elastomers (TPO, TPE, TPV, etc.)
Leistritz Group|Disclaimer / Privacy Statement|Imprint
Partner for modern technology
Flexibility starts in the mind
Extrusion Technology
A Pioneer in Extrusion Technology
from 1937 Development of an extruder based on existing screw pump designs. Foundation of the extrusion technology division.
1976 Establishment of AMERICAN LEISTRITZ EXTRUDER CORPORATION in Somerville, NJ, USA as a subsidiary in the extrusion technology field
1992-1997 foundation of sales agencies in France, Great Britain and Singapore
1998 Introduction of the new generation of ZSE High Performance (HP) Extruders with maximum screw revolutions of 1,200 rpm
2001 Conversion of the Extruder division of LEISTRITZ AG into
LEISTRITZ EXTRUSIONSTECHNIK GMBH
Organization of a new sales office in Italy
