Plastic Processing Data

Processing means setting up different parameters to produce a part which has all dimensions and tolerances per drawing and also meets the quality requirements. Process needs to be optimized to give us a part with minimum cycle time and best quality. First thing to start will be material properties (Physical, Mechanical and Thermal) which are provided by material supplier. These data can be used as guidelines for setting parameters on injection machine.

Material Properties

  • Material 
  • Melt Temperature (  or ° F)
  • Mold Shrinkage  (%)
  • Specific Gravity  (unitless)
  • Coefficient of Thermal Expansion, (in/in)/°F
  • Drying Temp (  or ° F)
  • Water Absorption % (24 hr@ 73 °F)
  • Heat Deflection Temp @264 psi
  • Specific Heat btu/lb/°F
  • Injection Pressure on Material (PSI)
  • Back Pressure on Material (PSI)
  • Melt Flow Index (g/10 min)

Process Setup Sheet

  • Press tonnage (tons)
  • Barrel Zones Temperature (°F)
  • Screw RPM
  • Gates Temperature  (℃  or °F)
  • Nozzle Temperature (°F)
  • Mold Zones Temperature (°F)
  • Clamp Force (ton)
  • Filling Time (sec)
  • Hold Pressure 
  • Cooling Time (sec) 
  • Injection Pressure (PSI)
  • Cushion (in)
  • Injection Speed (in/sec or mm/sec)
  • Ejector speed (in/sec or mm/sec)

ABS Properties

Categories:
PolymerThermoplasticABS PolymerAcrylonitrile Butadiene Styrene (ABS), Extruded
Density
1.02 – 1.20 g/cc
0.0368 – 0.0434 lb/in³
Average value: 1.05 g/cc Grade Count:115
Water Absorption
0.250 – 1.00 %
0.250 – 1.00 %
Average value: 0.448 % Grade Count:24
Moisture Absorption at Equilibrium
0.000 – 0.210 %
0.000 – 0.210 %
Average value: 0.180 % Grade Count:9
Water Absorption at Saturation
0.300 – 1.03 %
0.300 – 1.03 %
Average value: 0.796 % Grade Count:5
Maximum Moisture Content
0.0100 – 0.150
0.0100 – 0.150
Average value: 0.0256 Grade Count:9
Linear Mold Shrinkage
0.00200 – 0.00800 cm/cm
0.00200 – 0.00800 in/in
Average value: 0.00533 cm/cm Grade Count:75
Linear Mold Shrinkage, Transverse
0.00300 – 0.00800 cm/cm
0.00300 – 0.00800 in/in
Average value: 0.00591 cm/cm Grade Count:6
Melt Flow
0.100 – 35.0 g/10 min
0.100 – 35.0 g/10 min
Average value: 4.94 g/10 min Grade Count:115
Mechanical Properties
Metric
English
Comments
Hardness, Rockwell R
68.0 – 113
68.0 – 113
Average value: 101 Grade Count:60
Ball Indentation Hardness
65.0 – 110 MPa
9430 – 16000 psi
Average value: 93.2 MPa Grade Count:11
Tensile Strength, Ultimate
22.1 – 49.0 MPa
3210 – 7110 psi
Average value: 36.4 MPa Grade Count:31
Tensile Strength, Yield
13.0 – 65.0 MPa
1890 – 9430 psi
Average value: 40.4 MPa Grade Count:112
22.1 – 59.3 MPa
@Temperature -18.0 – 71.0 °C
3210 – 8600 psi
@Temperature -0.400 – 160 °F
Average value: 40.7 MPa Grade Count:1
Elongation at Break
3.00 – 150 %
3.00 – 150 %
Average value: 34.2 % Grade Count:71
Elongation at Yield
0.620 – 30.0 %
0.620 – 30.0 %
Average value: 5.57 % Grade Count:49
Modulus of Elasticity
1.00 – 2.65 GPa
145 – 384 ksi
Average value: 2.07 GPa Grade Count:57
1.50 – 2.60 GPa
@Temperature -18.0 – 71.0 °C
218 – 377 ksi
@Temperature -0.400 – 160 °F
Average value: 2.05 GPa Grade Count:1
Flexural Yield Strength
0.379 – 593 MPa
55.0 – 86000 psi
Average value: 69.2 MPa Grade Count:73
49.6 – 113.8 MPa
@Temperature -40.0 – 71.0 °C
7190 – 16510 psi
@Temperature -40.0 – 160 °F
Average value: 81.7 MPa Grade Count:1

 

L

Land (Gate Area): Gate dimension parallel to the direction of melt flow.

Land Area: The area of surfaces of a mold which contact each other when the mold is closed.

Light, UV Stabilizers & Absorbers: These additives increase the ability of the material to withstand the negative effects of light and UV exposure, thus increasing the service life of the material.

Linear Mold Shrinkage: The difference between the size of the part and the size of the mold cavity. Values given are often the average of a range.

Linear Thermal Expansion: The fractional change in length of a material for a unit change in temperature.

Liquid Injection Molding (LIM): The process that involves an integrated system for proportioning, mixing, and dispensing two-component liquid resin formulations and directly injecting the resultant mix into a mold which is clamped under pressure.

Low-Temperature Flexibility: The ability of a plastic to be bent without fracture at reduced temperatures.

Lubricant: Internal lubricants, without affecting the fusion properties of a compound, promotes resin flow. External lubricants promote release from metals which aids in the smooth flow of melt over die surfaces.