K 2007 Extrusion: Extrusion Outputs Go Through the Roof
Dramatic production demonstrations of cast and blown film set throughput records on the show floor in Dusseldorf. More high-speed demos were hosted by several German OEMs’ at their plants during the show. Not only have extruders speeded up, but several vendors displayed faster downstream chill rolls, winders, and surface inspection systems too.
Space does not permit repeating all the news reported in our September show preview. See Learn More below for additional developments from Alpine, Battenfeld Extrusion, Brampton, Cincinnati Extrusion, Davis-Standard, esde, Kiefel, Kuhne, Macro, Plast-Control, SML, and more.
BIGGER TORQUE MOTORS
Larger drive motors are part of the high-speed extrusion story, especially bigger sizes of permanent-magnet, synchronous torque motors. The latter have reached a new milestone—sizes big enough for 100-mm diam. extruders. Previously “syn-torque” motors could power extruders only up to 90 mm.
The largest syn-torque motor so far was launched by Parker Hannifin’s SSD Drives Div. in France with 22,100 Nm (430 hp) of torque. It turns at up to 600 rpm and is suitable for 100- to 120-mm extruders. Parker unveiled a whole new line of HT (high-torque) motors with built-in thrust bearings for extruders in three shaft heights and variable depth. A mid-size (7000 Nm) HT motor was shown at K by Parker’s customer Isoplast Srl in Italy, which makes extruders for pipe, tubing, and cast film. This motor also appeared on blown film lines from Dolci and Ghioldi.
Siemens has also upped the power of its 1FW3 line of syn-torque motors, designing sizes up to 18,000 and 20,000 Nm, suitable for extruders up to 120-mm diam. Siemens has actually built half a dozen motors up to 16,000 Nm, which Macchi of Italy is using on 100-mm blown film extruders. Macchi installed five of these over the past 12 months, including one in the U.S. Siemens also has built 14,000-Nm Reitorque motors for 90-mm Reifenhauser extruders and for 90-mm extruders from Windmoeller & Hoelscher.
To drive 100-mm extruders, Baumuller Nuernberg GmbH is raising the torque of its largest DST 315 syn-torque motor. It’s currently limited to 13,500 Nm of peak torque. The next version, due by June, will gain about 20% more torque.
A. Carnevalli & Cia. from Brazil (represented here by Mark One Machinery) demonstrated a five-extruder, five-layer blown film line driven by Baumuller syn-torque motors. Two 50-mm extruders have 38-hp motors; three are 60-mm with 65-hp motors. Carnevalli offers syn-torque motors on blown film lines with up to nine layers and nine extruders.
Several extruder builders announced modifications of screws and barrels to take advantage of the output capacity and energy efficiency available with syn-torque motors. Reifenhauser developed new low-temperature screws to boost efficiency of a 70-mm Reitorque extruder from 400 w/kg/hr to 300.
Baumuller displayed automation and control products such as a small, inexpensive approach to PLC extruder control. A printed circuit board with all major extrusion control functions can replace an independent PLC with a separate power supply. The board can be added to Baumuller’s Bmaxx drive, the frequency converter that controls an extruder motor, starting at about 500 Euros. Baumuller has software templates that can be used to control all extrusion line functions, from barrel and die temperatures to upstream feeding and downstream winders and cutters.
FILM & COATING AT WARP SPEED
Several companies claimed new productivity records at the show. Dolci Extrusion Srl of Italy (represented here by Kampf Machinery), ran five-layer, four-extruder LLDPE cast stretch film at the machine’s top rated speed of 600 m/min. On the last day of the show, Dolci cranked its FCL 5 Strato-Cast line up to 646 m/min. Output was close to 3520 lb/hr of 2-meter-wide, 20-micron film. The line featured the “world’s largest chill roll” of 1.5 meter diam. and a Contrawind 2PRO winder, enhanced for higher speed. Dolci also ran a Rotowind 2000 twin rewinder upgraded for faster robotic roll changes.
Colines in Italy ran 1-meter stretch film throughout the show at speeds of 500 m/min and outputs of 1320 lb/hr, making 2-in. rolls of hand stretch film every 16 sec.
Too big for the show floor, Gloucester Engineering’s new mid-sized Cast 3000 film line for 3-meter, five-layer LLDPE stretch film ran at the firm’s Vienna tech center during the show. It put out over 4400 lb/hr of 12-micron film at over 500 m/min, a 12% increase over previous systems. Higher outputs need faster cooling, so the new line uses a special chill roll upsized from 1 meter to 1.2 meter diam.
Dalaker Kunststoffmaschinen of Germany showed a new water-cooled polishing-roll stack that reportedly uses 25% less energy than typical chill rolls. Its GLW rolls have very thin surface metal—13 mm vs. the typical 30 mm—for better heat transfer to cool film at up to 2640 lb/hr.
W&H demonstrated its new 180-mm-diam. Filmex extruder, its largest, for stretch film and cast PP film at its in-house expo during K. The line made 25-micron, three-layer cast PP film 1.8 meters wide at 350 m/min and more than 2200 lb/hr, which W&H says is a record.
Reifenhauser reportedly broke a winding speed record at its in-house exhibit, where a new Midex rotary-arm unit wound cast PP film at 460 m/min and 3000 lb/hr. Servo motors control reel changes in 1.5 to 5 sec, depending on roll size. Tapeless crosscuts use an air stream and sensors to position film on the new roll. A contact slide roll with proportional valves controls winding pressure.
Blown film outputs also reached new highs at the show. W&H demonstrated a three-layer coex line with a 90-mm extruder driven by Siemens’ 11,000-Nm (192-hp) syn-torque motor, the largest at the show, and two 70-mm extruders with 150-hp syn-torque motors. The line ran at 1650 lb/hr with a 250-mm die and dual air ring. That’s 53 lb/in. of die circumference, which W&H says is a world record, up from 37 lb/in. three years ago, when W&H first demonstrated its dual air ring.
Hosokawa Alpine in Germany demonstrated the flexibility of its X die by running mLLDPE, HDPE, PP, and TPO on the same 3-layer die at the show with a dual air ring. Product changeovers were done with Alpine’s One-Touch automatic changeover system, which adjusts all process variables to a new recipe.
Extrusion coating outputs are also up. Davis-Standard ER-WE-PA in Germany offers a new high-speed line capable of up to 800 m/min, thanks to improvements in cooling and web handling. The extruder runs at up to 400 rpm.
New slot-coating die technology from Cloeren can adjust the flow passage to compensate for variations in the viscosity of the solution. The slot die was developed for a confidential application that requires very accurate coating thickness. The die also has a positioning device that can place it at precise distances from the substrate and a new high-accuracy delivery system with a tank and metering pump.
Cincinnati Milacron announced that it is now producing limited numbers of single-screw extruders in India. Its production there is focusing on smaller models with different designs tailored for North and South America and Eastern Europe.
Another Indian name in extruders is Kabra Extrusionstechnik Ltd., a licensee of Battenfeld Extrusionstechnik (BEX) in Germany for pipe and profile extruders. It’s 14% owned by BEX and sister company American Maplan. At K, Kabra introduced a multi-layer stretch-cling film extruder with liquid PIB dosing.
BETTER BARRIER SHEET
A new coex route to extruded barrier PET sheet was introduced by Amut SpA of Italy. It uses five extruders and a nine-layer feedblock and die from Extrusion Dies Industries (EDI). The structure is PETG-PET-regrind-tie-EVOH-tie-regrind-PET-PETG for thermoformed trays. Amut has built three so far. Regrind from PET sheet laminated to coex barrier film can’t be reused (it turns PET cloudy). But in this PET sheet configuration, the EVOH layer is so thin and starved by the feedblock at the edges, and there’s no PE, so the encapsulated regrind can be used.
Barrier PET sheet is typically made by laminating five-layer olefinic barrier film onto PET sheet at the first nip. But if the “bank” of PET at the nip gets too big, it makes invisible holes in the barrier film. Welex has developed a novel laminator that assembles film and sheet with a cool roll on the opposite side from the nip, which avoids breaking the barrier film. Welex has sold 10 of the new laminators in the past year to convert monolayer PET sheet into barrier laminates.
Dipiemme Srl of Italy showed an unusual “Roller Roof” system that forms clear corrugated roof panels between two heated calender rolls and a shaped cooling roll. The result is TD corrugation, unlike the MD corrugation typically produced by extruding roof panels through a hollow profile die. Dipiemme built the first of its roller sets (Italian Pat. 1265477) three years ago, but showed it for the first time at K.
PVC PROFILES & PIPE
Profile extruders are getting longer and outputs higher. Theysohn Extrusionstechnik’s latest TTM (Theysohn Torque Master) parallel twin-screw is longer to boost output—32:1 L/D rather than the usual 28:1. The Austrian company also offers a new choice of Allen-Bradley or Siemens controls.
KraussMaffei Berstorff introduced the largest size of its 32:1 L/D twin-screw PVC profile extruders using a new drive concept that gains 25% higher output. Model KMD 133-32/P (133 mm) produces up to 2200 lb/hr with dual strands.
Amut launched three new Max models of counter-rotating twin-screws with much higher motor torque to permit higher output. The BA 76 Cemax with a 38-hp motor produces over 550 lb/hr; BA 92 Nomax with 60-hp motor puts out over 814 lb/hr; and BA 114 Bimax with 97 hp runs over 1276 lb/hr.
Theysohn showed new calibrator plates with inserts that allow profile changes by replacing only the inserts in a plate instead of the whole plate. Also new is a configuration of a half-dozen or more dry calibrators that are 200 mm thick with patented inner cooling channels, instead of a solid, one-piece calibrator block.
Trinity Technology GmbH may be an unfamiliar name in calibrators. This five-year-old firm designs calibrators in Austria and builds them in China using German tool steel. It has a U.S. office.
Inoex in Germany showed a new camera system to inspect profile surfaces for flow lines produced by web supports inside the profile. Called Promex Objective, it was developed with Ascona GmbH in Meckenbeuren, Germany, a maker of visual measuring systems. The camera inspects stripes of light cast diagonally across the profile to reveal any surface ripples. The software grades the severity of the lines from 1 to 10, allowing processors to set a quality limit.
Pixargus GmbH in Germany, a spinoff from the RWTH Technical Univ. in Aachen (U.S. office in Charlotte, N.C.), introduced what it calls the first on-line profile dimension control with optical measuring heads. ProfilControl-Dimension HT-740 is installed between the die and calibrators.
HDPE PIPE & TUBING
Two OEMs brought new devices that adjust the diameter of pipe dies. Rollepaal bv in the Netherlands showed a new mechanical way to adjust HDPE pipe diameter on the fly by moving an outer shell in or out over a conical fixed center. Adjustment is made in 2-mm increments by manually moving spacers in or out. Three customers are testing the die, together with Rollepaal’s adjustable-diameter pipe cutter.
Rollepaal also recently extended the range of its adjustable cutters for PVC and HDPE pipe to go from 32 to 225 mm and from 110 to 520 mm. Previously the range was 60 to 125 mm.
Inoex introduced a new MaxFlexx feature that can be added to an existing die. It allows two alternative die gaps—either 8 or 25 mm—by retracting four movable pieces to open the larger gap. Two devices are now in the field. Inoex also extended the adjustability range of its Advantage polyolefin pipe calibrator sleeve up to 1200 mm diam.
Periplast Equipamentos Industriais in Portugal (represented in North America by its U.K. agent, Marshall & Co.) this year introduced an extruder, die, and downstream equipment (including a swarfless planetary cutter) to make up to 2-meter diam. solid-wall HDPE pipe, the largest size made today. (The first 2-meter HDPE pipe was made in 2004 by Pipelife Group in Norway on a Reifenhauser 150-mm extruder.)
Larger pipes need larger test devices. Zumbach Electronics increased the diameter of its Wallmaster ultrasonic wall-thickness gauge to handle pipe up to 23.6 in. OD. Zumbach also launched a new pipe surface-quality inspection system that operates at up to 500 m/min using three CCD cameras.
Two German firms, Drossbach GmbH and Gebr. Frankische Rohrwerke GmbH, announced a new partnership at the show that allows both firms to supply a full size range of pipe corrugators. Drossbach will build them for pipe diameters over 800 mm and Frankische will make smaller models.
In small corrugators, Corelco in France showed its NG (New Generation) high-speed, double-wall corrugators for 40 to 63 mm OD. Corelco can run 40-mm corrugated HDPE pipe at 21 m/min or about 330 lb/hr.
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