Lawton Machinery Group of De Pere, Wis., has introduced a new generation of compression molding machines specially designed for molding fuel-cell plates.
Lawton said fuel-cell plate materials developed by Bulk Molding Compounds Inc. of West Chicago, Ill., are highly filled with graphite material, using fast-cure resins. The thermoset materials demand fast pressing speeds and the instantaneous buildup of full clamping pressure upon full close.
Accurate flatness is critical, since the plates have very thin wall sections, in some cases, less than 1 millimeter, according to Lawton Machinery.
The new press is equipped with a servocontroller, accumulators and servovalves to distribute the hydraulic oil for higher pressing speeds and a faster and smoother transition to buildup of full clamping pressure.
The controller gives feedback to the servovalves, averaging the previous four scans. That enables the machine to have a “bumpless” transition from rapid close to high-pressure molding.
Another feature is a 45-degree adjustable gib guiding system, so the platen temperature has very little effect on the guiding clearance on tie bars.
Tel. 920-347-1983, fax 920-347-9183.