How do you calculate intensification ratio?
Once you have these two numbers you can calculate the machine’s intensification ratio with the following equation (see illustration): Ri = Maximum injection (plastic) pressure ÷ maximum hydraulic pressure for the injection unit.
What is eDART?
eDART (Dispatcher Application and Reporting Tool) allows generation and transmission owners to submit generation and transmission outage requests. eDART allows its users to manage their outage data by viewing the status of their outages and obtaining outage reports.
What is viscosity curve in injection molding?
The viscosity curve is a plot of the polymer viscosity vs. shear rate. Data is plotted here on linear scales rather than the log-log method. Interpreting this data will guide you to an appropriate fill time for this particular mold and resin.
What is scientific injection molding process?
Scientific molding is a process whereby the fill, pack and hold stages are treated separately to minimize fluctuations while improving overall product consistency. Separating the stages is also known as decoupled injection molding.
How is injection pressure calculated?
A general calculation for determining press size needed is as follows: Pressure (lb/in2) x Projected Area (in2) = Force (lb.) Here are a few other important tips for calculating the right press size for your plastic injection molded part.
How do you calculate cavity pressure?
different viscosities are reflected in cavity pressure, so cavity pressure of PC lamp holder should be 160 bar*K (the viscosity grade of PC). P = 160*1.9 bar = 304 bar for safety reasons, we take 1.9 times. F=P*S=304bar*380cm2=304kg/cm2*380 cm2=115520Kg or 115.5Ton, so 120T~130T injection machine can be used.
What is shear rate in fluids?
Shear rate is the rate at which a fluid is sheared or “worked” during flow. In more technical terms, it is the rate at which fluid layers or laminae move past each other. Shear rate is determined by both the geometry and speed of the flow.
What is viscosity in plastics?
What is viscosity in a plastic? Viscosity is the resistance to flow that the plastic faces when it is melted, ie if the plastic is too viscous it has difficulty draining through the nozzle of the injector or die of the extruder, as opposed to a plastic of low viscosity that will drain easily.
What is tonnage in injection Moulding?
The “tonnage” is the measure of force that is required to keep the tool closed during the injection process. This force is the main factor in determining the injection molding machine size required for producing the part.
What is Mould pressure?
During injection molding, the hold pressure, or pack pressure, is used to finish the filling of the mold and pack the part. The rule of thumb is that the hold pressure is 50%–70% of injection pressure. The hold pressure is applied against a pad or cushion of material (usually 1–3 mm).
How is mould shrinkage calculated?
Molding Shrinkage Calculation (s) The difference between the dimensions of the molded product and those of the cavity of the mold is expressed by the molding shrinkage ratio. 100 × (400 – 399) ÷ 400 = 0.25(%).