Thermoforming.

At this show, servo's the thing--driving all types of formers and trim presses.

Thermoforming is catching up with high tech, if this show is any indication. Exhibits in Chicago will showcase several advanced technologies that could change the face of thermoforming in coming years. Computerized process simulation will allow processors and tool designers to prototype in the computer instead of on the manufacturing floor, saving considerable time and expense. If "self-setting" controls prove their worth (only one example will be shown this time), even less experienced personnel will be able to achieve quicker startups with less scrap. And heating control is becoming more sophisticated each year, as quick-response heaters and infrared cameras provide real-time closed-loop control. In addition, quick-change tooling will make thermoforming a more "agile" process. Even on a more mundane level, the growing popularity of electric servo motors will make machines faster, quieter, cleaner, and more precise.

SIMULATION SOFTWARE 

If computerized process simulation can do for thermoforming anything like what it has done for injection molding, then thermoformers will have gained an extremely valuable new tool with the commercial introduction of C-Mold software from AC Technology, Ithaca, N.Y. A further refinement of the PITA software used in-house by GE Plastics, C-Mold models the thinning and stretching of the web during forming, enabling final part structural properties to be accurately predicted. It even models plug-assist forming in which the sheet has intermittent contact with the plug. C-Mold also shows a thermal "map" of the part as it cools in the mold.

SERVO DRIVE AND AUTO SETUP

All-electric servo-driven machines will be much in evidence. Suppliers see increasing demand for this type of drive, owing to its greater precision and control, as well as higher speed.

Irwin Research & Development, Inc., Yakima, Wash., which builds only servo-driven machines, will demonstrate a new continuous, roll-fed Micro F/T machine first seen at Interplas '93 in England.

The Micro F/T is Irwin's first trim-in-place model (see PT, Jan, '94, p. 50). It has 24 x 20 in. mold area and 5-in. max. draw. It will be shown with Micro Phaser II control and Irwin's Product Retrieval System (PRS), which consists of a robot arm that reaches into the mold, receives products ejected from the top platen, and transports the parts to a stacker.

Irwin will also show its servo-driven Magnum trim press (largest in its line, with 20 x 50 in. platen), which has a new treadle system that provides faster and more accurate trimming by reducing side-to-side movement.

Electric servo drive is standard on upper and lower platens--and optional on plug assist--of the new Series 3200SD thermoformer from Sencorp Systems, Inc., Hyannis, Mass. The machine also has servo-driven indexing, which Sencorp has offered for some time. This model has 30 x 33 in. forming area, 6-in. max. draw, and quartz ovens (gas oven optional).

Sencorp will also show an older machine with servo-driven indexing and pneumatic platen drive, the Series 2500 (30 x 33 in., 5-in. draw). Its new feature is a touchscreen controller hung on a pendent that allows the screen to swivel.

Electric servo-driven indexing is just one of the new features on an updated Model 900-15 continuous pressure former from Zed Industries, Vandalia, Ohio. Also new are a larger forming area (22 x 22 in.), pin-chain indexing system (instead of hitch-feed), touchscreen computer, stacker with counter and product ejector, and optional gas oven.

Adolf Illig Maschinenbau GmbH of Germany (which has several distributors here) will show an RDKP 72d high-speed pressure former with a new electric servo-drive system. Servo drive reportedly enables precise, repeatable setting of forming-platen and plug-assist strokes and speeds, as well as automatic recall of setups from computer memory storage. This roll-fed machine operates at up to 45 cycles/min with a separate in-line punching and stacking station. It also incorporates QMC devices.

An unusual feature on this machine is an "SPS" automatic self-setting "expert" system that's said to enable even unskilled operators to start up a new job while generating little scrap. The operator enters into the controller data on material type, width, and thickness, as well as forming height and index length. Then the computer automatically sets the proper times, strokes, speeds, and temperatures. A version of this feature was first seen at Interplas '90 in England (PT, Jan. '91, p. 81).

A variety of new control features will be highlights of the HD-333 large single-station vacuum former shown by Z.M.D. International, Inc., Paramount, Calif. This machine (shown last fall at Interplas '93 in England) has an infrared pyrometer that "reads" sheet temperature and controls the heating cycle. Energy-management software in the heating system is said to save 40-60% in energy costs. A photoelectric sensor monitors sheet sag and moves the bottom heaters downward as needed. There's also a laptop computer interface between the operator and PLC, with 60-megabyte hard disk to store setup files. And a 24-in. safety light curtain protects the operator and stops the machine if the curtain is crossed.

This machine also has a clamp frame that adjusts in size from side to side and front to back in minutes and 10-minute QMC capability. Top and bottom platens can be locked in any vertical position, which aids in releasing very heavy or undercut parts. A bottom-load/unload system allows large sheets to be loaded and large parts to be unloaded through the bottom of the machine.

Other new products from Z.M.D. (also shown at Interplas '93) include the BFI-622 continuous roll-fed vacuum former (24 x 24 in.) with QMC system (under 1 min) and pneumatic traversing knife to cut parts from the web. Also new are the VJR-522 single-station blister former (24 x 24 in.) and Z2027 roller-press die cutter (27 in. wide) that reportedly changes tools in 5 min.

Brown Machine Div. of John Brown Plastics Machinery, Beaverton, Mich., will bring its electric servo-driven C-3015 continuous, cut-in-place former (also shown at NPE '91). What's new is an automated product handler that collects parts in a stack up to a certain count and then pushes the stacks onto a beat conveyor. The accumulator plate accommodates multiple rows of product in the sheet-travel direction, which is said to increase productivity up to 50% over other trim-in-place machines. Brown's TCS-1000 microprocessor control is now standard on all units with the new handling system.

A new servo-driven vertical trim press, Model 130-PV2, will be introduced by Lyle Industries, Inc., also of Beaverton. It will be trimming PET in-line with a Lyle 130-FM servo-driven thermoformer. The PV-series trim press is said to be unusually versatile in that it allows quick conversion from steel-rule to matched-metal trim tooling. "Servo nip" feeding establishes accurate location of parts for trimming--independent of the thermoformer's indexing accuracy. Trimmer platen also has four-post guidance.

Servo-driven indexing and hydropneumatic platen drive are said to account for the 40-cycles/rain speed limit of the KL 52 BFS cut-in-place, continuous pressure former being introduced to the U.S. by Kiefel Systems, Succasunna, N.J. It uses cost-effective steel-rule dies and includes an automatic stacker/counter and video control with diagnostics.

Servo-driven indexing is one of the new features on the updated VTP-15 vertical trim press to be shown by Edward D. Segen & Co., Devon, Conn. High accuracy and precise control adjustments are the advantages cited. Another new feature is improved flexibility: The user can quickly detach the web-indexing table and replace it with a manual feed table for individual parts or an automatic pick-and-place device for high-production applications. Also new is the ability to adjust the press force from 15 to 30 tons to accommodate either steel-rule or punch-and-die trimming.

PP FORMING ADVANCES

OMV of Italy and its U.S. operation, OMV-USA, Genoa City, Wis., plan to operate a "fifth-generation" in-line extrusion and thermoforming system in order to demonstrate that thermoforming is now fully competitive with injection molding for PP containers, offering equal quality, lighter weight, and higher outputs. OMV has launched the E74.1 system, which uses the same dual shuttle mold as before to extend cooling time, but now extrudes horizontally into the mold instead of vertically. Laying the mold flat provides greater support, allowing use of larger tools. As an example, OMV will run a 40-cavity mold producing 40,000 PP cups/hr. At the show, OMV plans to change molds and all downstream tooling in 2 hr to produce 25,000 16-oz PP deli containers/hr in 15 cavities.

Another new aspect of this machine is the capability to incorporate numerous secondary operations right in the machine: in-mold labeling, hole punching, lip rolling, and bar coding. The machine also features closed-loop temperature control via an i-r camera that scans the sheet. Automatic adjustment of the chains stretches the sheet as it begins to sag.

Another new OMV machine is the FC-75 thermoformer, dedicated to PE and PP lids. It's designed to overcome problems of weak vertical "skirts" in PP lids that result from excessive thinning. Special individual clamping and in-mold trimming is said to provide a stiff rim and eliminate shrinkage induced problems of trim accuracy.

Also addressing the PP lid problem will be Gabler of Germany, appearing in the booth of its U.S. representative, FGH Systems Inc., Denville, NJ. New cut-in-place tooling for making PP deli lids clamps on a larger diameter than previously and blows the material with compressed air against the cavity before cutting. This reportedly provides a thicker skirt on the lid.

To eliminate sagging problems with PP, Kiefel Systems will introduce to the U.S. its Model KVH 83 free-standing pre-heat station with its own unwind stand, This unit impinges hot air on the sheet as it travels up and down in five closely spaced vertical loops formed by a series of rollers. In cases where a former's speed is limited by heating capacity, this compact unit can increase throughput while adding only 9.7 ft in overall length.

OTHER NEW HARDWARE

North American processors may be unfamiliar with the U.K. firm of C.R. Clarke & Co. Ltd., which has an office in Aston, Pa. It will present a line of benchtop and freestanding single-station vacuum formers (manual and automatic) up to 18 x 20 in., as well as thermal sheet bending equipment and edge-polishing machines.

Formech Inc., Central Islip, N.Y., will introduce to the U.S. its British line of large, automated, single-station thermoformers. Formech will also show two new smaller single-station models: automatic roll- or sheet-fed model A660 (19 x 25 in.) with guillotine cutoff and semiautomatic model FMP-1 (52 x 24 in.) with 16-in. draw depth.

A new patented heat-control system will be highlighted by Thermoforming Technologies, Inc., Seabrook, N.H. Designed for large parts, this system uses an array of noncontacting infrared pyrometers, together with a DEC Vax computer and touchscreen display to provide feedback control of quartz heaters.

A new QMC system for high-production, multicavity molds will be shown by Segen & Co. The new 438C quick-change cylinder is an air-actuated coupling that holds and aligns mold cavities in place. With this approach, cavities can be interchanged without removing the entire tool.

What to Look For

* Computer simulation eliminates guesswork.

* All-electric-servo drives are 'in.'

* 'Smart' former does its own setup.

* 'No-sag' heater for PP.

* QMC system interchanges cavities, leaves mold base in place.