Thermoset Plasticator

Plasticator for Thermoset Material

The LMG Plasticator is designed and built to preheat and preform thermoset materials such as BMC, Epoxy and Phenolic for transfer or compression molding. The preheater combines two steps, preforming and preheating the material into one step and delivers very accurate shot sizes. Plasticating the material results in molding cycles that are more consistent and produces molded parts with higher quality.

The material is melted in an electrically heated, low-wear plasticating cylinder and a reciprocating screw.

A slow-running hydraulic motor drives the screw. The screw speed can be set infinitely within its operating limits. The material to be plasticated is fed against the lockable output nozzle in the screw metering zone. A manual valve is used for the setting of backpressure. The material volume is set with the screw stroke. Continuously variable intermediate settings are possible between the units minimum and maximum stroke capabilities. The changeover and turn-off signals are delivered by a position measuring system. Position input is done at the operator interface screen.

The screw is hydraulically moved forward for the output of the thermoset material. The material exits the barrel through a round opening, which is the same diameter as the screw chosen.

After each partial (or complete) output from the plasticator, the hydraulically-driven knife cuts the extrudite and closes the collection area for the next plasticating cycle. The cut-off device is a guillotine knife manufactured of through-hardened H13 tool steel for long life. Further possibilities like screw decompression are variations that can be pre-set at the control unit.
Screw sizes are available from 40 to 100 mm with shot size capability from a few ounces up to 10 pounds.

Feature Benefit
1.
 15 HP hydraulic power unit
  • Multiple times the HP of competitive units to provide greater ability to process high shear compounds at increased speeds.
2.
 Integral pressure transducer with screen readout for back-pressure monitoring
  • Immediate feedback on back pressure, allowing system parameters to be optimized and monitored.
3.
 Through-hardened H13 tool steel knife
  • Extended life expectancy.
  • Virtually maintenance free.
4.
 High grade screw
  • Specially designed for processing of thermosets.
5.
 PLC control system with position feedback with proportional screw speed control
  • Accurate shot size.
  • Easily changed shot size.
  • Multiple extrudite capable of four programmed shot sizes.
6.
 Extra-large reservoir
  • Allows settling of contaminants, egress of air and stabilizes oil temperature swings.
7.
 Water over oil heat exchanger
  • Ensures oil temperature stays within limits when unit placed in hot environment.
8.
Variable displacement pump with flooded suction
  • High efficiency with long life when compared to variable speed electric drive units.
  • Low noise and longer life due to the elimination of cavitation.
9.
 Four (4) adjustable feet and casters
  • Allows fixed positioning to allow for integration with other equipment.
  • Allows adjustable positioning to a fixed point and a fixed level.
10.
 Capacity to make multiple shot sizes
  • Four operator-programmable shot sizes add flexibility to operate multiple presses with up to four different cavity sizes simultaneously.
11.
 Insulation blankets for barrel
  • Ensures most reliable heat control and reduced energy losses.
12.
Easy to operate controls
  • Operator friendly controls increase efficiency of set-up and operation.
  • Additional modules can be added without high investment costs
Accessory Equipment Extrusion Device
Agitating hopper for non-free running materials. Hopper capacity 22 cu. ft.
Hydraulic stuffer for BMC-DMC-SMC polyester. Pressure 725 psi, capacity 130lb.
The hydraulic knife closure can be used to plasticate materials having a low viscosity, in order to prevent flash.
The Screw Pre-Plasticating Process
Material is fed from the hopper into the screw and barrel assembly. The cutoff knife is in the normally closed position.
Material is pre-plasticated as it passes through the heated barrel and compressed to about 95% of its natural density against the cutoff knife. The screw and drive unit are pushed back.
When the preset length is reached, the knife goes up, the screw moves forward to eject the preform, the knife comes down again to cut it off.

The preform is then fed either manually or by means of an automatic feeding device into the mold.

The cycle is ready to be repeated.

Transfer Time / Material Preheating
Curve a) Transfer time with pre-plasticated mass
5 seconds
Curve b) Transfer time with preheated mass
10 seconds
Curve c) Transfer time with cold mass
20 seconds
Contact us via Online Request OR Phone: (920) 347-1983
Email: info@lmgpresses.com

We will respond within one business day.

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