NPE Newsfinder: Injection Molding

The abundance of injection molding news at this year’s show is staggering. There are more and bigger all-electric machines than ever, including first-time introductions by several suppliers. Electric technology is also taking new forms, such as beltless drives and “direct-pressure” clamping without a toggle. Energy-saving electro-hydraulic hybrids are also evolving.

Look for micro-molders making parts of less than half a gram, as well as lots of big machines that have dainty footprints. Vertical machines will be present in force; gas assist and multi-material molding will be everywhere; and whole new machine lines will be launched into the marketplace. Molders looking for a bargain will face a daunting array of machines from unfamiliar Brazilian and Far Eastern vendors. And don’t miss the unusual or first-time demonstrations of special techniques like melt oscillation (Scorim process), hollow-parts molding (Die Slide process), gas counterpressure, gas assist paired with LIM or multi-material molding, and new water injection molding (it’s like gas assist without gas).

 

All-electrics get bigger

Electric servo-driven presses will be more numerous at this show and physically larger than ever before. At least 11 companies will display all-electric machines this year, compared with two at NPE ’97. Hulking on the show floor will be the largest all-electric model ever yet built: a 1550-ton Ultima UN machine from Ube Machinery Inc., Ann Arbor, Mich. It will be accompanied by last year’s largest electric press, now the second largest at 1100 tons. Ube and partner Niigata in Japan are jointly developing even bigger electric models than these.

The Powerline all-electric series from Ferromatik Milacron, Batavia, Ohio, is also moving up in size. Its newest and largest model is 935 tons (up from 750).

The Japanese-built Milacron Fanuc series of all-electrics has grown larger, too, with the new Roboshot “i” series that extends from 17 to 385 tons. (see PT, April ’00, p. 38).

Toyo of Japan (represented by Maruka U.S.A. Inc., Rockaway, N.J.) will bring a new 300-ton electric machine that extends its Plastar Si Series beyond the previous top end of 200 tons.

Also extending the range of its electric machines—at both ends of the scale—is Toshiba Machine Co. America, Elk Grove Village, Ill. It will bring new models of 22, 186, 242, and 386 tons. (Earlier sizes are 44, 66, and 110 tons.)

New SE-S electric machines from Sumitomo Plastics-Machinery (America) LLC, Norcross, Ga., are a 20-tonner, the smallest in the line, and a 253-ton intermediate size. Sumitomo will also bring its novel SK Control option for its electric machines—a shutter-type check valve that provides tighter shot control by eliminating backflow. By turning the screw a few degrees in the opposite direction, the shutter closes before the start of injection.

Meanwhile, Nissei America Inc., Anaheim, Calif., will get the prize for the smallest all-electric machine at the show. Its HM-7 Denkey (7.6 tons), mounted on a wheeled cart, has the industry’s first electromechanical “direct-pressure” clamping mechanism. All other electric clamps use toggles. Nissei officials say ball-screw-driven direct clamping (also to be shown on the new ED3000 machine of 167 tons) is better than a toggle for ultra-precise molding.

This machine, as well as two other new Nissei models at NPE, use beltless direct-drive servo motors, in which the ball screw is an extension of the motor spindle. Such a mechanism is said to be simpler, quieter, and cleaner (generating no dust) than a belt drive. It also reportedly has faster acceleration/deceleration response. Direct drive will appear at the show on Nissei’s high-speed ES200 (22 tons) and ES6000H (301 tons). Conventional belt drive will be shown on the new ES5000 238-ton electric machine.

Also new from Nissei is the all-electric DCE120, a 130-ton, two-color machine with dual molds on a rotating platen.

Three other firms will make their all-electric debuts in North America. Kawaguchi Inc., Buffalo Grove, Ill., will show its first horizontal all-electric model. (It makes vertical electric presses in Japan but does not offer them here.) The KXE 55-tonner has two-stage injection.

Mitsubishi (sold here by MHI Injection Molding Machinery, Inc., Addison, Ill.) will unveil its ME Series of 390, 500, and 610 tons. Models of 715, 935, and 1100 tons are also planned. They carry the new MAC VII controller, wide platens, and an open base for three-way parts removal.

The first all-electric machines from Italy, made by Bodini Presse s.r.l., will be shown here by PlastiMatix LLC of Farmington Hills, Mich. They come in 28 to 330 tons, soon to be followed by a 550-tonner.

Niigata Engineering Co., Itasca, Ill., which introduced its electric line to the U.S. last year, will show four machines from 55 to 500 tons. One will demonstrate a servo core pull.

 

Check out the ‘hybrids’

If you’re not willing to pay 20-40% more for an all-electric machine, several new electro-hydraulic hybrids on display are intended to provide significant energy savings at lower upfront cost. At the small end of the size range, Boy Machines Inc., Exton, Pa., plans to introduce a hybrid machine of 88 tons, but no details were available at press time. Krauss-Maffei Corp., Florence, Ky., is bringing a KM600-3500 C3 two-platen machine of 660 tons, which sports the new HPS plasticating unit with electric screw drive.

Electric drive on the screw, rotary table, and ejectors are modifications to a basic Gluco 100-ton vertical press that will be shown by PlastiMatix LLC, Farmington Hills, Mich. Whereas Gluco specializes in thermosets, this press is designed for thermoplastics. It has horizontal injection and a four-post cantilevered clamp in place of Gluco’s standard C-frame. Less deflection is said to result.

Two Japanese machine builders are showing a new style of hybrid clamp. The new Nadem line of Meiki America Corp., Elk Grove Village, Ill., and the Tuparl EH series from Sodick Inc., Torrance, Calif., both have hydromechanical clamps in which servo-driven ball screws open and close the clamp quickly. After the mold closes, a hydraulic locking mechanism engages the ball screw, and small hydraulic cylinders apply clamping force (see PT, April, ’00, p. 50). This arrangement reportedly combines finer and more uniform pressure control with the greater speed and position accuracy of electric motors. Both machine lines also have electric screw drives.

Van Dorn Demag Corp., Strongsville, Ohio, will show two different types of hybrids at NPE. One is a new high-speed version of the 500 HT toggle press (500 tons) with an electric screw drive, “super clamp,” and injection accumulators.

Van Dorn will also show two versions of the Demag Ergotech El-Exis machine, one of which has not been seen before. Demag displayed a prototype high-speed version of the El-Exis at K’98 in Dusseldorf and will have a 265-ton El-Exis S model in Chicago. It has electric screw drive and an electric motor with a “hydrostatic gear” transmission to power two hydraulic cylinders on the five-point toggle clamp. (The hydrostatic gear system utilizes a small amount of oil in a localized closed loop with no return to tank.) Injection is accomplished with a gas accumulator and variable-volume hydraulic pump. The latter also powers the nozzle motion, core pulls, and ejectors. This concept reportedly achieves power savings of 40%.

Shown for the very first time at NPE will be the “standard” El-Exis E version in a 165-ton model. It differs from the S version in replacing the injection accumulator with an unusual servo-motor system. The AC motor on the injection end turns in one direction to drive the screw directly. When the servo motor runs in the reverse direction, it disengages the screw drive but instead powers a hydrostatic gear that drives two hydraulic injection cylinders (see schematic). Power consumption is said to be similar to an all-electric machine.

Two other firms showing electric-screw hybrids will be Arburg Inc., Newington, Conn., and Sandretto USA, Inc., Freedom, Pa.

 

Mini and micro molders

The smallest machine at the show is the 2-ton, air-operated AB-300-4 from A.B. Machinery, Montreal. This new semi-automatic model has 1/4-oz shot capacity and is designed as a desk-style, “sit-down” unit with floor-pedal control. Electronic timers on the front panel regulate injection, clamping, and ejection.

For molding really small parts, you’ll have to see the 5.5-ton MicroSystem from Battenfeld of America, West Warwick, R.I. In its first U.S. appearance (it debuted at K ’98), this all-electric machine has shot capacities from 0.45 to 1.45 g. Its unusual three-stage injection system (plasticating, dosing, and injecting) can fill at pressures up to 61,500 psi. A rotary table allows molding to overlap cooling and ejection so that cycle times can be as short as 5 sec.

Another micro-molding entry will be introduced by Arburg. The new 17-ton Allrounder 220 S 150-35 will demonstrate metal- or ceramic-powder molding at the show. Arburg is also adding a 77-ton toggle machine (Allrounder 320 K) to its current 28- and 40-ton offerings.

Battenfeld is also showing a new version of its CDC hydraulic presses (16.5 to 220 tons), in which the operator control station has been moved to a position between two safety gates covering the mold area and nozzle area. This gives the operator a closer view of the action while standing at the controls. CDC presses are now available in North America with new Unilog B4 controls (also available on TM series toggles).

Updated versions of the Butler benchtop 9-ton mini-press will be shown by MCP Equipment of the U.K. (represented by Tomken Tool & Engineering, Inc., Muncie, Ind.). The MCP Butler 12/90 H.S. unit has a 9-ton, air-operated clamp and 0.4-oz shot capacity. It has two-stage, screw/plunger injection and Omron controls. MCP also has a new hydraulic version of this machine and a vertical-clamp pneumatic model.

New features will also be shown on benchtop machines from Mini-jector Machinery Corp., Newbury, Ohio. A 12-ton Model 55 will have an optional 2-oz shot capacity and oversized “V” mold. A 10-ton Model 70 will show several hardware and software updates.

AmeriPlas Machinery Corp., Cleveland, which has made low-cost vertical insert molders, is introducing its first horizontal press (30 tons). Controls for this and other models feature a new interactive “Answer Man” that both asks important questions of the operator and helps solve molding problems.

Moduline S-Series small machines (44 to 180 tons) from Husky Injection Molding Systems Ltd., Bolton, Ont., will show new quick-color-change and mold-protection capabilities.

To replace its long-selling PS-type machine, Nissei will introduce the PN60E compact, precision-molding machine with 70-ton hydraulic clamp. It has a new injection mechanism and is optimized for extremely uniform plastication.

Van Dorn Demag is replacing its ET toggles with the new Cadence series of 28 to 110 tons. They are built in Germany but designed specifically for the U.S. market, particularly the higher performance end (PT, March ’00, p. 12).

 

Bigfoot is out

Though there will be plenty of big presses on the floor, they will occupy modest real estate. Most are two-platen hydromechanical presses with reduced footprint. There’s also an unusual “21/2-platen” design that boasts added advantages.

HPM Corp., Mt. Gilead, Ohio, is showing off its recently updated and “Americanized” NextWave two-platen machines with retractable tiebars (PT, March ’00, p. 48). Two models of 880 and 1375 tons will be shown.

Another two-platen series with retractable tiebars is available from Po Yuen (To’s) Machine Fty. Ltd. in Hong Kong. Size range is 600 to 3000 tons.

From Korea comes a new line of two-platen machines. A 950-tonner will be shown by LG International (America), Inc., Englewood Cliffs, N.J.

Van Dorn’s Caliber two-platen machines of 1100-3300 tons have a new twin-cylinder injection unit that cuts machine length even more and accommodates a wider range of screw/barrel packages. It will be shown on an 1100-tonner.

Mitsubishi/MHI has two large-machine entries in store for NPE. One is the third generation of MM III two-platen presses (1450-4400 tons), whose new features include the MAC-VI color CRT control, UB screw for improved productivity, “jet-purge” circuit for quicker color changes, clamp-braking circuit for increased position accuracy, and a built-in oil cleaner.

Those features (except for an upgraded MAC VII control) are also found on the brand-new MMJ series of 610 to 1200 tons. These “21/2-platen” hydromechanical machines have almost as small a footprint as a two-platen design (22% shorter than a fully hydraulic machine), plus reduced platen deflection for very precise molding, Mitsubishi says. Instead of clamping on the tiebars at the four corners of the mold, the MMJ has a large central clamp cylinder that travels along with the moving platen (see schematic). Like a two-platen machine, it uses a diagonal pair of small rapid-traverse cylinders to open and close the mold, plus locking nuts to grip the tiebars before clamping. Dry cycle is said to be 18% shorter than a fully hydraulic press. Both the MMJ and MM III series offer a new low-pressure molding option in which the injection speed is controlled by the cavity pressure. It is said to permit fast injection of large automotive parts without flashing or short shots.

Saving space overhead to leave room for a robot is the goal of new low-profile structural-foam presses from Wilmington Machinery (PT, Jan. ’00, p. 11). The company also has redesigned the built-in hot-runner manifold system for these machines: Now each valve-gate nozzle can be individually controlled for maximum flexibility in mold filling.

 

Get vertical

As at the last NPE, vertical presses for insert molding will make a strong showing:
To satisfy growing interest in insert molding of larger parts for cars and appliances, Autojectors Inc., Avilla, Ind., is bringing out its largest model yet. The HCR-280 is a 280-ton press with four-station rotary table.

Boy Machines has partnered with automation specialist Panzer Tool Works, Inc. of Elk Grove Village, Ill., to develop the Rotoslide rotary indexing system for Boy’s 24.2-ton vertical machine. The table slides out of the clamp area, indexes to the next position, and then slides back. Ball-screw drive is said to make it extremely accurate.

New V2 Series of insert molders from Trueblood, Columbus, Ohio, has an enclosed base and footprint up to 50% smaller than competing machines. Vertical injection is standard. The two-tiebar clamp with pull-down cylinder in the machine base eliminates a bulky C-frame. Patented “Veer” shuttle uses slots in the lower platen and small hydraulic cylinders to slide mold bases in and out of the clamp toward the operator, not side to side. The machine needs no external lubrication, suiting it to clean-room use. Although 15 and 40 tons are standard sizes, Trueblood has built a 10-ton benchtop unit. Custom models can also have horizontal injection or a rotary table.

A new 50-ton vertical-clamp/vertical-injection machine will debut at NPE from Wabash MPI, Wabash, Ind. The WPR 50/150 has a four-station rotary table and 5.5-oz injection unit. It is controlled by a DataTrend III system and Allen-Bradley Panel View-600 touchscreen.

Van Dorn Demag also sees a need for larger insert-molding capability. It has introduced a larger Newbury Vertical machine of 140 tons to replace the former 125-tonner. A new 80-ton Newbury Vertical model will also be shown.

Two overseas suppliers will be highlighting vertical presses for footwear and other applications. Pacific Machine Co., Ltd. of Taichung, Taiwan, supplies rotary shoe machines with 20-40 stations, capable of molding up to three colors. Main Group of Italy, represented here by Horizon Molding Services, Atkinson, N.H., supplies rotary and single-station verticals of 66 to 660 tons. It specializes in shoe machinery but also supplies other insert-molding applications. Its presses can inject up to four colors in the same cycle.

 

New machine series

Two brand-new series of medium-sized machines are being launched at NPE by Van Dorn Demag. Its new Pinnacle Series has a more robust five-point toggle that is designed to reduce platen deflection and overall machine length. For quick barrel changes, it has quick disconnects and an Automatic Barrel Identification System in the controls that adjusts the machine settings to the new barrel. Whereas Van Dorn’s previous toggle machines had two barrel choices, the Pinnacle Series offers three: standard, high-pressure, and extra-high pressure. Two variable-volume “smart” pumps have the electronics on the pump rather than on the hydraulic valves, which is said to provide faster response. Two Pinnacle presses of 140 and 280 tons will be shown. When the full line comes out by the end of 2001, it will reach 625 tons.

In hydraulic-clamp machines, Van Dorn’s new Spectra Series replaces the mid-range HP Series. It comes in 500, 730, and 880 tons. The 500-tonner will be shown with a variable-speed pump drive that provides energy savings of 30-70%. Key features of the Spectra series are its modularity (it shares bases between sizes), wide platens, up to 15% lower height, and full tiebar support to allow for stack molds. Spectra models also use a reportedly unique three-port hydraulic valve that is said to offer the advantages of a servo valve without its sensitivity to contamination.

Ferromatik Milacron will be showing its new Magna T line of mid-range toggles from 170 to 450 tons (PT, April ’00, p. 13). Also new is a smaller two-platen hydromechanical unit, the Maxima 550.

HPM will show its updated line of Universal II toggles from 60 to 560 tons (PT, March ’00, p. 48).

Sandretto USA will show off its new Series Nine series of compact toggles from 73 to 562 tons (PT, Oct. ’99, p. 13).

NPE will be the North American introduction of Kawaguchi’s new standard line of toggle presses, the KX Series. The range is now 110-393 tons, and by fall it will span 55 to 720 tons. They boast larger and more rigid platens, longer strokes, new DV mixing screw, new PC-based EZ-2000 controller with real-time graphical shot displays, and new energy-saving digital hydraulic feedback control.

The new standard line of hydraulic-clamp machines from Mitsubishi is the MSJ series, ranging from 90 to 500 tons. Among the many improvements over the earlier MJ series are larger platens and tiebar spacing, greaseless tiebars, dual injection cylinders, simplified hydraulic piping for “zero leaks,” 20% more rigid platens, jet-purge circuit, and new MAC-VII controls. Models up to 320 tons also have three-way take-out and variable-volume pumps.

Arburg is breaking out of the small-machine category with its largest model ever, a brand-new 300-ton, 29-oz hydraulic-clamp press, the Allrounder 630 S.

Netstal Machinery Inc., Devens, Mass., will show the new top end of its SynErgy line, the model 6000 (660 tons). It is accompanied by new models 4000 and 5000 (440 and 550 tons).

Two firms will introduce high-speed injection systems. Sumitomo will show its HP-Plus Option, in which a small gas accumulator is mounted directly on the injection unit. And Meiki is showing one of its new MC-AS high-speed, high-pressure machines for thin-wall, tight-tolerance parts like connectors. It uses an accumulator, servo valve, new high-response injection control, special check valve, long nozzle, and six-stage clamp-pressure control (low initial pressure aids venting during fast fill).

 

Unfamiliar nameplates

NPE will be a prime opportunity to get acquainted with numerous overseas machinery vendors from countries other than Europe or Japan:

Brazil: Reed-Prentice Ltd., West Springfield, Mass., is getting back into horizontal toggle machines with a line from 75 to 2000 tons built by former Reed licensee Industrias Romi, S.A. Another Brazilian visitor, Himaco Hidraulicos e Maquinas Ltda. of Novo Hamburgo will demonstrate a 165-ton machine at the show. It makes toggle presses from 66 to 550 tons, including horizontal, vertical, two-color, and rotary models.

India: Closed-loop injection-pressure control is a new feature on the Indigo series of horizontal presses, built in India by Cincinnati Milacron Ltd. and marketed here by Autojectors. They include toggles of 33 to 440 tons and hydraulic models of 500-1000 tons.

Korea: LG International is showing a new 180-ton hydraulic press.

Taiwan: Asian Plastic Machinery Co., Ltd., Taoyuan, will show a 550-ton, two-platen, hydromechanical machine and 90-ton direct hydraulic press. Size range is 30 to 3200 tons, including toggle presses and all-electric machines (30-180 tons).

CLF machines of 80 to 3500 tons are built by Chuan Lih Fa Machinery Works Co., Ltd., Tainan Hsien. Models from 88 to 275 tons have a new base that allows three-way parts removal.

Lien Fa Injection Machinery Co., Ltd., Taichung Hsien, builds hydromechanical, two-platen machines from 88 to 2750 tons, toggles of 88 to 242 tons, PET preform machines, and rotary shoe machines.

Nan Rong Mechanical Co., Taipei, will show a 275-ton toggle press. Its line ranges from 121 to 2420 tons. Also, TMC of America, Inc., Winchester, Va., will show its new E2 toggle machine with MACO 4000 control. And press builder Lien Yu Machinery Co. of Tainan Hsien, will also be at the show.

Hong Kong: A new generation of five-point toggle machines with 35-40% greater injection-pressure and plasticating capacity comes from Chen Hsong Machinery Co., Ltd. Jetmaster MKIV models of 80, 130, and 170 tons will be shown, as well as a 550-ton hydraulic-clamp press.

CBCL Inc., Great Falls, S.C., will show a Hang Seng press. A 150-ton toggle will be shown by Po Yuen (To’s) Machine Fty. Ltd. It makes 50-500 ton toggles and 600-3000 ton hydraulic presses with new retractable tiebars.

A 176-ton toggle in the Potenza line will be shown by L.K. Machinery Co., Ltd. The full line from 88 to 495 tons has variable-volume pumps and Barber-Colman controls.

A Multi Mat two-color machine with a rotary mold will be shown by Y.K. Seiki Ltd., which builds toggles from 22 to 495 tons.

China: Haitian Machinery Co., Ningbo, will introduce its faster HTW Series of toggle presses (99 to 1188 tons), which have enlarged tiebar spacing. It will show 97- and 308-tonners.

 

Special technologies

Here are brief notes on some of the special-purpose machines and components to look for at the show (see our Show Guide for more details):

Gas counterpressure: HPM and Van Dorn will demonstrate this technique for reducing sinks and molded-in stresses.

Gas assist: New components for hollow-core molding will be introduced by Alliance Gas Systems (Chesterfield Township, Mich.), Beaumont Runner Technologies (Erie, Pa.), Cinpres Ltd. (Ann Arbor, Mich.), GAIN Technologies (Sterling Heights, Mich.), and RIX Industries (Benicia, Calif.). In addition, Engel Canada Inc., Guelph, Ont., is demonstrating liquid silicone molding with gas assist. IMS Co., Chagrin Falls, Ohio, is newly distributing gas-assist equipment from NitroJection Corp. Bauer Compressors, Inc., Norfolk, Va., will also show gas-assist components.

Water injection: A new technology analogous to gas-assist, but using water, will be showcased by Herzog USA Inc., Haverhill, Mass.

Microcellular foam: The MuCell process will be highlighted by Trexel Inc., Woburn, Mass., and its licensees—Arburg, Engel, Ferromatik Milacron, and Husky.

Polyester BMC: A larger stuffer is new from Apex Plastic Technologies, South Elgin, Ill.

Marbleizing: A new screw/barrel kit will be shown by Kawaguchi.

Gas venting: Kawaguchi will also introduce its SGV (Simple Gas Vent) technology. By venting gas through the nozzle end cap during injection, drying time can be reduced by half, company spokesmen say. SGV is reportedly adequate for removing surface moisture and for avoiding splay in ABS. It is not recommended for PET or PBT.

Hollow-parts molding: JSW Plastics Machinery, Inc., Elk Grove Village, Ill., will show its Die Slide Molding process here for the first time.

In-mold laminating: Krauss-Maffei is introducing to North America the Decoform process for low-pressure back-molding of decorative coverings via injection-compression on a horizontal press. A door panel will be molded on a 1300-ton machine. K-M will also highlight the Decopress technique for accomplishing the same goal via open-mold injection into a vertical press.

Melt-oscillation molding: Cinpres will provide a rare live demonstration of its Scorim process.

Multicolor/coinjection molding: Battenfeld will mold a desk-drawer front using coinjection of unreinforced PP over PP filled with natural fiber (flax). The TPO handle will be added by a third injector using gas assist.

Addmix of London, England, is showing an “entry-level” coinjection system in which two materials are fed alternately into a single screw and barrel (similar to Ferromatik Milacron’s “mono-sandwich” approach).

MGS Enterprises, Inc., Germantown, Wis., will show how to convert a standard injection press to multi-material capability. MGS’s Universal Multi-Shot (UMS) machine is a small injection unit that mounts vertically atop an existing press. It comes with its own hydraulic power pack and Allen-Bradley controls. MGS will introduce a twin-barrel version of the UMS to permit three-shot molding.

New from Presma Corp., East Brunswick, N.J., is the Roto HSP/2/BIC, a 10-station, 55-ton rotary coinjection and structural-foam machine that has four barrels.

It used to be the largest all-electric machine ever built, but this Ube 1100-tonner will be accompanied in Chicago by an even bigger brother of 1550 tons.

New ways to power injection machines are exemplified by this novel hybrid from Van Dorn Demag. A servo motor rotates one way to turn the screw and reverses direction to power the hydraulic injection cylinders.

New MMJ Series of large presses from Mitsubishi almost matches the footprint of two-platen machines but avoids platen deflection with a central clamp cylinder.

Nissei’s HM7 Denkey is not only the smallest all-electric machine at the show (7.6 tons), but also the first electric machine that uses direct-pressure clamping instead of a toggle.

To meet demand for larger insert-molded parts for cars and appliances, Autojectors came out with this 280-ton model.

The emerging trend toward micro-parts molding has spawned the all-electric, 5.5-ton MicroSystem from Battenfeld.