The invention relates to a method for qualitatively and/or quantitatively classifying injection-molding tools in tool categories and determining preferred intervention ranges and/or manipulated variables for adapting injection-molding machine parameters in the case of changing ambient conditions and/or determining the influence of disturbing effects on the injection-molding process, comprising the following steps: a) providing an injection-molding machine having the injection-molding tool which is to be classified and which is intended for the determination, b) performing at least one injection-molding cycle with injection-molding machine settings in order to obtain a qualitatively adequate injection-molding part, c) determining a quotient Q=p/s or Q=sn/se characterizing the tool from c.1) a pressure rise p during the compression phase of the injection-molding cycle and the melt volume V displaced during the compression phase or c.2) a melt volume Vn displaced during the holding-pressure phase and the melt volume Ve displaced during the injection phase, wherein c.3) the corresponding screw travel s, sn, and se is measured in order to determine the displaced volumes V, Vn, and ; Ve, d) providing at least one limit value (G1 . . . Gx . . . Gn), wherein one or more recommendations for preferred intervention ranges or manipulated variables for adapting adjustment parameters of the injection-molding machine are associated with ranges (Q<G1; G1<Q<G2; . . . Gn-1<Q<Gn; Q>Gn) for the values of the quotient Q, e) determining in which of the ranges (Q<G1; G1<Q<G2; . . . Gn-1<Q<Gn; Q>Gn) the value of the quotient Q lies, and f) outputting the preferred intervention ranges and/or manipulated variables for adapting the machine parameters of the injection-molding machine which are associated with the determined range.

In a method for determining at least one parameter for the description of the compression behavior of a material processed in a molding machine, at least a part of the processed material is introduced into a mold cavity via a distribution system and a gate, and the processed material solidifies in the mold cavity. A compression test is performed in which a volume storing the material is modified and a measurement of the resulting pressure modification is conducted or a pressure applied onto the material is modified and a measurement of the resulting modification of the volume is conducted. A parameter for the description of the compression behavior is calculated based on the result of the compression test by using a mathematical model. The compression test is conducted when the gate is at least substantially solidified or when the hot runner is closed.

Systems and approaches for controlling an injection molding machine having a mold forming a mold cavity and being controlled according to an injection cycle include injecting a molten polymer into the mold cavity according to the injection cycle using a screw that moves from a first position to a second position. Upon completion of the injection cycle, a recovery profile commences where the screw is moved to the first position. Using a sensor, at least one variable is measured during the recovery profile. At least one operational parameter of the injection molding machine is adjusted based on the at least one measured variable during the recovery profile.

An injection molding machine includes a cylinder that accommodates a molten resin, a discharging nozzle, a piston that discharges the molten resin from the discharging nozzle, and one or more processors configured to execute the following functions. The functions include calculating a target pressure at which a flow rate of the molten resin discharged from the discharging nozzle becomes an indicated flow rate, controlling a pressure of the molten resin in the cylinder such that the pressure becomes the target pressure, acquiring a temperature of the molten resin in the cylinder, and acquiring a pseudo-plastic viscosity corresponding to the temperature of the molten resin. The target pressure is calculated based on the indicated flow rate, the temperature of the molten resin, the pseudo-plastic viscosity, and the size of the discharging nozzle.

In order to improve the consistency of molded products as viscosity shifts throughout a run, a controller of an injection molding machine executes a calibration cycle in accordance with a mold cycle. The controller analyzes a plurality of sensed melt pressure values during the calibration cycle to determine one or more calibration metrics. The controller then uses the calibration metrics when executing each mold cycle of the run. More particularly, during each mold cycle of the run, the controller detects a plurality of sensed melt pressures prior to and during a fill phase of the mold cycle and compares the plurality of sensed melt pressures to the one or more calibration metrics to predict cavity pressure for a pack and hold phase of the mold cycle. The controller then adjusts a set point pressure for the pack and hold phase based on the predicted cavity pressure.

Rheological measurement systems for use with systems including pressurized polymer melts and/or other viscous materials are described. In one embodiment, a rheometer is connected to an associated system with a bent, curved, or bendable tube to permit the rheometer to measure rheological properties in locations where the rheometer could not otherwise be located due to the presence of obstructions. Embodiments including rigid straight tubes for connecting a rheometer to an associated system are also described. In another embodiment, a flow-through rheometer is connected to an industry standard ?-20 thermowell aperture that is typically used for attaching temperature and pressure probes to a vessel containing a viscous material such as an extruder or injection molding system. The rheological measurement systems described can have improved tube resistance and thermal strength.

A molding method produces a molded part from a polymer starting material in a molding machine, in particular an injection-molding machine. In the method, the polymer starting material is plasticized and/or fused, and at least one monomer in the gaseous state is supplied to the polymer starting material.

For each of different resins R, a zero shear viscosity ?o of each resin R is obtained by using a conversion function expression whose parameters are a melt flow rate (MFR) and a set temperature of a heating cylinder and is registered. Also, a purge resin required amount Wu corresponding to a viscosity difference ?d between the zero shear viscosity ?of of a former resin Rf and the zero shear viscosity ?os of a succeeding resin Rs is registered. When resin switching is performed, the zero shear viscosity ?of of the former resin Rf and the zero shear viscosity ?os of the succeeding resin Rs are obtained by inputting the MFR of the former resin Rf and the MFR of the succeeding resin Rs to a molding machine controller, the viscosity difference ?d between the zero shear viscosity ?of of the former resin Rf and the zero shear viscosity ?os of the succeeding resin Rs is obtained, an amount of a purge resin required for resin switching is obtained as a purge resin required amount Wu, and at least the obtained purge resin required amount Wu is displayed.

The present invention provides a molding machine that can easily detect viscosity of resin in a cylinder without advance preparations. An injection molding machine (10) includes an ultrasonic viscosity sensor (20), and the ultrasonic viscosity sensor (20) includes an ultrasonic vibration portion in contact with resin filled in a cylinder (12).

In injection-molding a conductive material, prolongation of an injection molding cycle and occurrence of defective appearance of a molded article are reduced, and the molded article is given uniform conductivity. An injection molding apparatus has a heating injection means which heats a conductive material to a temperature that allows the conductive material to melt and flow, and which injects the conductive material to a mold. The mold has a plurality of conductive portions at least at a portion of a surface defining a cavity, the conductive portions being insulated from each other. A predetermined voltage is applied to the conductive portions. A static mixer is provided in an area including a tip portion of the heating injection means and a flow path of the conductive material.