BLOW MOLDING: Electric Machines Starting to Purr
Growing use of electric drives in blow molding machinery gathered steam at the K 2010 show, as suppliers rolled out new all-electric
and hybrid models for extrusion blow, injection-blow, and stretch-blow production. There was also a strong emphasis on higher output as demonstrated by a new dual-parison hydraulic wheel machine that claims production rates approaching that of PET.
Other new developments included novel lightweighting options for PET containers, an automatic handle-insertion system, a novel mold-change system with removable inserts, and a vision-based quality-management system for rigid containers. (Additional news was reported in our September K show preview.)
ALL-ELECTRIC EXTRUSION BLOW
Uniloy Milacron (uniloy.it) introduced the first all-electric sequential coextrusion machine for producing 3D automotive air ducts. The twin-parison UMA 12 SeCo2 EnergiaZero has a clamp force of 12 metric tons in a tiebarless configuration. W. Muller GmbH (wmuller.com) developed a patented sequential coextrusion head for the machine.
Bekum (bekum.de) launched the production model of its EBlow x07 D series all-electric shuttle machine. The series is available with platen widths of 350 to 700 mm and clamp force of 8 to 24 metric tons (m.t.) in single and twin-station versions.
In development is an all-electric continuous-extrusion shuttle from Automa (automaspa.com) for bottles up to 6L. The Apex AT480D, slated for commercialization early next year, has 10 m.t. of clamp force and can run up to six cavities. The double-carriage machine has a dry cycle of 2.2 sec.
Plastimac (plastimac.com) showed off its latest all-electric Plastiblow PB5E/DL. The double-station extrusion blow unit comes with 80-mm horizontal extruder and a smaller vertical extruder for producing 5L jerry cans with a view stripe. The head design is said to facilitate precise parison control and rapid color change.
For injection-blow, MBM Maschinenbau Muhldorf GmbH (maschinenbau-muehldorf.de) unveiled its second-generation fully-electric machine. The Unimax 50FE-EcoSpeed has a 50-m.t. clamp and is about 20% more energy efficient than its predecessor. It is designed to process a wide range of materials while offering improved process control and quiet operation. Cleanroom compatibility suits it to pharmaceutical and cosmetic/personal-care bottles.
The new 85S hybrid injection-blow unit from Jomar Corp. (jomarcorp.com) produced 4-oz clarified PP medical bottles in 10 cavities at 3500/hr at the show. Another new injection-blow machine from Jomar is the Model 20 for small bottles.
PUSHING THE ENVELOPE ON SPEED
Wilmington Machinery (wilmingtonmachinery.com) highlighted dual-parison capability for its SB (Small Bottle) Series of extrusion blow wheel machines (introduced at NPE 2009), boosting production output to near PET levels. It molds 80- to 250-ml containers for single-serve dairy, juice, yogurt, and food. With 40 stations, a two-parison model has demonstrated 6-sec cycles for an 80-ml HDPE bottle, a rate of 800 bottles/min. With 60 stations, output could be 1200/min.
Kautex Machines Inc. (kautex-group.com) showcased its KLS machine range with integrated downstream automation for quality management and product traceability. Off-spec parts were identified via leak detection, part weighing, and vision inspection.
There was also strong emphasis on improved speed and output in stretch-blow molding, as demonstrated by KHS GmbH’s (khs.com) InnoPET Blomax Series IV reheat model, which now produces 0.2- to 2L bottles at 72,000/hr, vs. the previous rate of 43,200/hr.
SIPA SpA (sipa.it) launched a new rotary stretch-blow molder that’s said to offer increased production flexibility for different size containers. The SFR 6 EVO has six cavities and is the smallest version in the series, producing up to 13,800 bottles/hr. It is ultra-compact and can be equipped with preferential heating. It has produced 1L water bottles weighing just 16 g (with a stretch ratio of 18) at 2200/hr.
Nissei ASB Co. (nisseiasb.co.jp) has boosted PET bottle output with a new two-row, one-step stretch-blow machine and also introduced a reheat model for wide-mouth hot-fill applications.
SAVING ENERGY & MATERIAL
Sidel (sidel.com) showed SmartWeight, a lightweight 500-ml PET water bottle weighing less than 10 g with a much stiffer base for better mechanical performance and appearance. The company’s overstroke base technology consists of synchronizing the blow molding process with the rise of the base, thus increasing the lengthwise stretching rate of the preform. This helps to decrease the quantity of material in the base and ensures more uniform distribution.
Krones AG (krones.com) introduced its NitroPouch concept to produce a “featherweight” 330-ml PET water bottle weighing just 4.4 g with wall thickness from 0.06 to 0.1 mm. Nitrogen gas at 1.5 bar introduced during filling and capping gives the bottle sufficient rigidity. Bottles meet topload requirements for warehouse storage and transit even after internal pressure falls to 1 bar. A minimum nitrogen pressure of 0.3 bar is required to to maintain adequate stiffness for a good consumer “feel.”
An optimized oven configuration helps reduce power consumption by up to 45% and heating time by up to 15% with Sidel’s SBO Universal2 Eco stretch-blow molder. It uses fewer heating modules and fewer lamps per module.
New FlexWave microwave heating technology from Krones uses significantly less energy than infrared ovens. This oven concept for Contiform stretch-blow machines requires no start-up time and offers processing flexibility because it is not affected by preform color, initial temperature, grade of PET, or proportion of recyclate. It can even process two-color preforms. Fewer heating stations means less waste in case of an emergency stop.
Krones also launched the ProShape alignment and temperature-control module for molding oval or asymmetrical containers. Inserted between the standard oven and blowing wheel, the module uses aluminum molds to achieve a precise temperature profile for producing unusual bottle designs or for lightweighting oval containers. Production rates can be up to 2000/hr.
Meanwhile, Siapi S.r.l (siapi.it) launched its HandleMatic 360° concept, which permits integration of a handle for any type of container during or after blowing. The system has been successfully implemented in North America with Siapi’s EA2S blow molding machines for 5-gal refillable PET water jugs.
Sidel has developed the 3L DeepGrip PET bottle with a deep blow molded grip that requires no external handle. Developed with PTI-Europe, the container uses Sidel’s punching-conforming technology to produce a single-material bottle and handle suitable for water and vegetable oil. The bottle is formed in a standard mold where the reversed cavity of the future grip is preformed, creating two “ears.” The bottle is then conveyed by its neck with grips for transfer to the conforming mold. The two ears are pressed against each other via punching to obtain the deep grip. The pistons turn the material over and form the grip, while simultaneous blowing at a pressure of less than 20 bar prevents bottle deformation.
For greater production flexibility, Sidel developed the Modulomold system, which enables several different bottles of the same size (up to 0.7L) to be produced in a single mold using removeable inserts. The bottles have two shared parts (the labeling area and the base) while the shoulder and/or body can be customized using the inserts. It takes less than 30 sec to change a set of inserts.
Sidel also showed the SafeSense stretch-blown HDPE bottle as an option to extrusion blown HDPE containers for dairy products. It is 20% lighter thanks to the preform conditioning that precisely controls thickness distribution. Airtight capping is also possible without an aluminum sealing lid. Stretch-blown HDPE bottles also offer higher output and less waste than extrusion blowing.
A vision-based quality-management and process-monitoring system was shown by Agr International Inc. (agrintl.com). The OptiCheck finish/seal surface module monitors and manages finish defects and helps ensure proper closure fit and function. A multi-camera imaging system provides 360° gauging of container finishes from 20 to 80 mm. The OptiCheck sidewall uses four cameras for 360° inspection for common defects in translucent materials.
Here’s a quick guide to fixing four nettlesome problems in processing PET bottles.
INJECTION MOLDING AT NPE: Molding Exhibits Show Off Cell Integration with Multiple Processes & Operations
If you’re interested in lightweight composites, IML, LSR, multi-shot, inmold assembly, barrier coinjection, micromolding, variotherm molding, foams, energy-saving presses, robots, hot runners, and tooling—they’re all here in force.
Advances in materials, feedblock/die technologies, and winding can help processors develop more sophisticated cast-stretch products.