Residence Time is the length of time that the material is held at melt range temperatures. For any given machine and mould combination, the residence time is determined by two factors: the length of the overall cycle time and the shot size setting. Residual Stress is a general term that describes the level and pattern of stress which is left in the part after it is removed from the mould. Runner Layout is the approach used to get material from the machine nozzle to the gates. Shear Heating is a term that describes how friction caused by flow can increase the melt temperature of the material as it is flowing during the filling phase. Shear Rate is a way to describe how quickly the velocity of the material changes from the mould wall to the center of flow for a given cross section. The size of the shear rate gives an indication of the shape of the velocity profile for a given flow situation. Shear Stress is the result of the force that is generated in a plastic material to overcome its resistance to a particular flow situation. Shear stress is the product of the viscosity of a material and the shear rate. It is reported in units of stress or pressure (psi or Pa). Shear Thinning is a way of describing how the physical effects of orientation influence the flow behavior of the material. Shear thinning causes the material's viscosity to drop when it is made to flow within a certain shear rate range. Shot Composition describes the relationship between machine barrel settings and the events which occur during the moulding cycle. The shot size setting and the transfer point give the machine information about how material is to be injected into the mould. The distances for these settings correspond to volumes of material that play a role in different portions of the moulding cycle. Shot Size Setting is a machine control setting which limits how far back the screw will travel as it rotates in the cooling/plastication phase of the moulding cycle. The shot size setting is measured as a distance from the front of the barrel. You can set the shot size to any distance along the length of the barrel up to the stroke of the machine. Split Points are locations in a mould cavity where a melt front will split up and advance in more than one direction at the same time. Split points are also referred to as branch points, flow junctions or nodes. Thermal Properties describe how a given plastic material will behave during the exchange of heat. They are an important factor in determining how succeptible a material is to shear heating; they also characterize how quickly a given material will cool down. Transfer Point is a position on the length of the barrel which signals the machine to switch from filling at constant flow rate to packing at constant pressure. When set properly, it corresponds to the fill time for the mould.