ADDlTlVE - A substance added to a plastic compound to alter its characteristics. Examples are plasticizers, and flame retardants.
ALLOY - A combination of 2 or more plastics which form a new plastic.
AMORPHOUS- A plastic material in which the molecular structure is random and becomes mobile over a wide temperature range.
ANNEAL ~ To heat a moulded part up to a temperature just below its melting point and slowly cooling it back; down to room temperature. This relieves moulded stresses.
ANlSOTROPlC SHRlNKAGE -Shrinkage that occurs more in one direction (usually the direction of flow; reinforced materials shrink more across the direction of flow) than another.
AUTOMATIC OPERATlON -The term used to define the mode in which a moulding machine is operating when there is no need for an operator to start each cycle.
BARREL - A metallic cylinder in which the injection screw (or plunger) resides in the moulding machine . Also called CYLINDER.
BLEND - A mixture of 2 or more plastics.
BOSS - A projection of the plastic part, normally round, which is used to: strengthen an area of a Part provide a source of fastening; or to provide an alignment mechanism during assembly.
CARTRIDGE HEATERS - Pencile-shaped electrical heater devices sometimes placed in moulds to raise the temperature level of the mould. Especially beneficial when moulding high-temperature crystalline materials.
CAVlTY - A depression or female portion of the mould which creates the external plastic part surface.
CORE - (a). An extended or male portion of the mould which creates the internal plastic part surface.
(b). A pin or protrusion designed to produce a hole or depression in the plastic part.
(b). A pin or protrusion designed to produce a hole or depression in the plastic part.
CHECK RING - A ring shaped component that slides back and forth over the tip end of the screw. he check ring eliminates the flow of molten material backwards over the screw during the injection process.
CLAMP FORCE - The force in tons, that the clamp unit of a moulding machine exerts to keep the mould closed during the injection process.
CLAMP UNIT - . This is used to close the mould and keep it closed against injection pressure created by the injection process.The clamp unit also contains the ejection mechanism.
COLD SLUG WELL - A depression (normally circular) in the ejection half of an injection mould, opposite the sprue, designed to receive the first front, or “cold" portion, of molten plastic during the injection process.
COMPRESSION RATIO - A factor that determines the amount of shear that is imparted to plastic material as it travels through the barrel. It is determined by dividing the depth of the screw flight in the feed section by the depth of the screw flight in the metering section.
CONDITIONING - Exposing a moulded part to a set of conditions (such as hot oil) which impart . favorable characteristics to the product.
COOLING CHANNELS - Drilled holes or channels machined into various plates or components of an injection mould providing a flow path for cooling medium (such as water) in order to control the
temperature of the mould.
COUNTERBORE - A recessed circular area. Commonly used to fit the head of an ejector pin (return pin, sicker pin, etc.) in the ejector plate
CLAMP FORCE - The force in tons, that the clamp unit of a moulding machine exerts to keep the mould closed during the injection process.
CLAMP UNIT - . This is used to close the mould and keep it closed against injection pressure created by the injection process.The clamp unit also contains the ejection mechanism.
COLD SLUG WELL - A depression (normally circular) in the ejection half of an injection mould, opposite the sprue, designed to receive the first front, or “cold" portion, of molten plastic during the injection process.
COMPRESSION RATIO - A factor that determines the amount of shear that is imparted to plastic material as it travels through the barrel. It is determined by dividing the depth of the screw flight in the feed section by the depth of the screw flight in the metering section.
CONDITIONING - Exposing a moulded part to a set of conditions (such as hot oil) which impart . favorable characteristics to the product.
COOLING CHANNELS - Drilled holes or channels machined into various plates or components of an injection mould providing a flow path for cooling medium (such as water) in order to control the
temperature of the mould.
COUNTERBORE - A recessed circular area. Commonly used to fit the head of an ejector pin (return pin, sicker pin, etc.) in the ejector plate