While selecting injection
moulding machine the following specifications are required to be evaluated.
Maximum swept volume cc / max. shot weight gr.
Calculation of max. shot weight for a material.
Maximum metering stroke in mm.
Dependence of quality of melt for consistency of moulding.
Maximum injection speed g/s or cc/s
How it ensures melt to spread throughout when in fluid condition- before it freezes. Its relationship with freezing time.
Maximum injection pressure Kg/cm2
How it overcomes resistance to flow during filling and; pressure phase on account of flow ratio and; viscosity.
Maximum Injection Power. Kgcm/sec.
How it takes care of difficulty in filling for thinner walled and high flow ratio parts.
Plasticizing rate g/s or Kg/hr.
How it influences cycle time.
Clearance between Tie bars and platen size mm x mm
How it accommodates mould.
Maximum daylight mm and mould open stroke mm
Its significance for ejection of deep parts.
Minimum mould height
Its relationship with mould open stroke and daylight
its dependence on cavity pressure and method to compute cavity pressure.
Torque Kgm and rpm
Torque requirement for -viscosity of- melt.
Power supply frequency 60 or 50 Hz.
Its influence on speeds.
Pump-motor rating. kW
To match the application - usage of machine.
• Conventional / Proportional and Cartridge valve Hydraulic Controls
NO LOAD CYCLE TIME
It indicates the time for non processing part of the cycle time