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201 is suitable for medium quality products like

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Unformatted text preview: used for low quality items such as disposable packaging or cheap children’s toys. Terms Terms in Injection moulding Short Weight: The Shot Weight of a machine is defined as the weight of plastic produced at the nozzle in a normal cycle (without a mould) in PS (specific gravity 1.05). INJECTION PRESSURE This is the pressure in the barrel at the point of injection, expressed in kg/cm2 or kbar. A higher L/D ratio produces greater Injection Pressure. The greater the Injection Pressure the better the the better the quality of product produced. Terms Terms in Injection moulding INJECTION STROKE The distance that the screw travels during an injection stroke, up to 4 * diameter. INJECTION VOLUME Theoretically, the injection volume is the length of the injection stroke multiplied by the cross sectional area of the screw. only around 90% of that Injection Volume gets injected. INJECTION SPEED INJECTION RATE :This is the volume of melt produced by the screw, expressed in cm3 per second. SCREW ROTARY SPEED CLAMP FORCE The melt is injected into the mould under very great pressure, which the mould halves, and any other components or cores, must be able to resist in order to maintain their shape and to avoid any seepage. The larger a component is, the greater the pressure and so, the greater the Clamp Force required. MOULD OPENING STROKE This is the distance that the moving mould half moves from mould closed to mould open. MOULD HEIGHT This should be called Mould Thickness, Moulding • Moulding refers to shaping of plastic melt inside the mould. INJECTION MOULDING MACHINE FOR PREFORMS 1987 HUSKY XL 225 P THREE THREE BALANCING TRICKS I can summarize the successful and consistent moulding to three balancing tricks; Flow balancing – part geometry dependent. Heat balancing in one cycle time- dependent on design of cooling in the mould and cooling water supply system. Uniform freezing of melt in the mould. – Dependent on cooling design and supply system. Any unbalancing on the above three bal...
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