SMC leads composites equipment news.

SMC flow simulation now has companion programs for bonding and for GMT (glass-mat thermoplastic sheet) forming. Those were some of the equipment developments at the recent SPI Composites Institute annual meeting in Cincinnati. (See PT, April '95, p. 37 for new resins and additives.) The show also highlighted new SMC/GMT press controls and auxiliaries, as well as new pultrusion systems and low-cost RTM dispensers.

SIMULATION FOR SMC & GMT

New advances in process simulation for compression molding were announced by The Madison Group: Polymer Processing Research Corp., Madison, Wis. Cadpress finite-element compression-molding simulation, which was introduced last year (PT, June '94, p. 41), can now run on Unix workstations as a faster alternative to PCs. The program is also said to be more accurate and user-friendly than before.

In development is a new companion program for GMT. Unlike the SMC version, Cadpress GMT will calculate mold filling, shrinkage, warpage, and fiber orientation (it's designed for chopped-fiber sheet). Commercial release for Unix platforms is expected this summer.

New Cadbond software calculates the final shape and stress distribution of bonded SMC assemblies. It can predict bond delamination and the influence of metal inserts. Release is scheduled for later this year.

ADVANCES IN PRESS CONTROLS

For dielectric cure monitoring and SMC press control, Micromet Instruments, Inc., Newton Centre, Mass., came out with the ICAM-3000 multi-press controller. While previous models monitored and controlled only one press, this unit can handle up to six presses from as far away as 250 ft. It monitors material viscosity, temperature, pressure, and an additional analog variable on each press. The dielectric curve representing viscosity changes can itself be analyzed for up to 65 variables, each of which can have upper-and lower-limit alarms. The system also records part counts and SPC data. Price is $8500 per press for a six-channel unit and under $10,000 per press for a four-channel version.

Several new user-friendly control features have been added to presses from Dieffenbacher of Germany (represented by Girard Associates, Inc., Middleburg Heights, Ohio). The operator interface is now a Windows-based PC instead of a PLC. The PC reduces cost and interfaces more easily to other computers and software.

The PC can now overlay graphs of multiple process variables at one time. As the operator moves a vertical rule along the x-axis to highlight a particular cycle or point within a single cycle, the y-axis numerical values appear on the screen.

The PC control also provides more on-screen diagnostic documentation, including the operator's manual and schematics of the hydraulic system and electrical I/Os. The user can click on any part of the diagnostic display to access "help" messages. Clicking on any part of the I/O screen brings up text information on that I/O point.

Dieffenbacher's new "GMT Problem Definer" calculates three process values for each cycle: total molding-energy input, average thickness of the formed material, and parallelism and force differentials at the four corners of the press. Each variable has three color-coded tolerance bands - green (good), yellow (borderline), and red (out of tolerance).

NEW SMC AUXILIARIES

The big news in SMC surface-quality analysis is that Diffracto Ltd., Windsor, Ont., has purchased the LORIA system from Ashland Chemical Co. Diffracto will now offer both LORIA and D Sight profile-measurement systems.

In addition, Diffracto has "unbundled" its D Sight software to reduce its price. Previous systems costing $95,000 combined features for measuring plastics, glass, and metal. The new Series 4 contains only plastics software for 865,000.

RP/C Alliance Corp. of Southfield, Mich., has added to the group of companies it represents as system integrator. New to the group is D&F Corp., Sterling Heights, Mich. It builds secondary tooling and fixtures for bonding, punching, and routing.

Another new partner is SI Handling Systems, Inc., Easton, Pa. Its Robolite Cartrac conveyor systems move parts between work cells for secondary operations. One major SMC molder is using the system to index parts from post-mold cooling to deflashing, drilling, and application of adhesive or liquid gasketing.

Other news from RP/C Alliance includes the latest hot-air bonder from Nemeth Engineering, Crestwood, Ky. This simplified air-impingement system uses low-pressure (6-15 psi) air from a blower instead of compressed air. Cost is thereby reduced and hot air can now be recycled for energy efficiency. The system also blows ambient air to cool the part. Hot-air bonding is not as fast as RF bonding (which Nemeth also supplies) but hot-air bonders cost one-third less. Typical hot-air bonding cycles are 45 sec, vs. 20-30 sec with RF.

Another RP/C partner, Perceptron, Inc. of Farmington Hills, Mich., offers a new approach to quality control. Perceptron's TriCam laser camera now can scan the surface of a molded part and generate a CAD wire-frame image. It will tell whether that image matches the original CAD design stored in memory. A TriCam sensor with controller and software costs around $40,000, not including scanning robot.

NEWS IN PULTRUSION

PTI, div. of MMFG, Twinsburg, Ohio, has redesigned its Pulstar line of machines, creating two families - the 2000 EX and 2000 MX. Both have a new touchscreen controller mounted on a swing arm so that the machine can be operated from the right or left side. Both series also have wider pullers than previous models and hydraulic instead of manual puller-height adjustment.

The "basic" EX line has few options but can be delivered in eight weeks. It comes with open die bed, roll-off table, and a walk-through space between the saw and puller. New colored safety lights above the machine indicate when the power is on and when the machine is running. There is one choice available: limit switch or encoder wheel for regulating saw position.

PTI's modular MX series has all the features of the EX series plus a choice of open die bed or platens, electroluminescent or CRT display, and color or monochrome screen. Other options include host-computer communications, higher pulling speeds and forces, and special saw options for cutting parallel streams to different profile lengths. For two different cuts, a saw with two-zone programmability is offered. For more than two different cuts, multiple saws can be provided.

Another pultrusion equipment supplier, Composite Process Equipment (CPE), Inc., Haslet, Texas, introduced two- and four-bladed saws to cut different lengths from a multi-stream die. Each saw is programmed independently.

LOW-COST RTM SYSTEMS

Three new developments for RTM were shown by RTM Systems Inc., Indianapolis. The "Spartan" or Low-Cost Injection System is priced around $6000. This stripped-down system comes without a mast and boom (optional) but does include materials circulation from the gun head, which keeps fillers in suspension and helps dispel air bubbles from the catalyst stream.

RTM Systems also brought out two inexpensive variable-ratio injection systems. The two-component VR2 and three-component VR3 are designed for epoxies; the VR3 can handle an extra stream for the accelerator. A new optional interlock prevents injection unless both resin and catalyst ball valves are turned on.