A mold apparatus for forming a molded part includes a mold body, a mold cavity formed in said mold body, a plurality of valve gates associated with said mold body, and a controller in communication with said plurality of valve gates. The controller is programmed to time opening of each valve gate based on a selected flow rate required to eliminate weld lines in the product.

A method and apparatus for injection molding of plastic material into a cavity of a mold by means of at least one injector whose opening and closing occurs through an electronic control unit and wherein an undesired opening of the mold caused by any overpressure of the plastic material injected into the cavity of the mold is detected by means of transducers and corrected by means of the electronic control unit. The transducers are arranged outside the cavity of the mold.

A method of determining a solution state of a gas in a plastic melt used in a plastic shaping method includes: (vi) providing the plastic melt together with the gas in a chamber, (vii) altering—in particular reducing—a volume of the chamber to alter a pressure of the plastic melt together with the gas—in particular increased from a first pressure value to a second pressure value, (viii) introducing the plastic melt into a shaping cavity, (ix) computing at least one compression parameter characteristic of the compression behaviour of the plastic melt, in particular a modulus of compression, from the first pressure value and the second pressure value, and (x) determining from the at least one compression parameter whether the gas is substantially completely dissolved in the plastic melt and/or a solubility limit of the gas in the plastic melt is determined from the at least one compression parameter.

A mold apparatus for forming a molded part includes a mold body, a mold cavity formed in said mold body, a plurality of valve gates associated with said mold body, and a controller in communication with said plurality of valve gates. The controller is programmed to time opening of each valve gate based on a selected flow rate required to eliminate weld lines in the product.

A method and apparatus for injection molding of plastic material into a cavity of a mold by means of at least one injector whose opening and closing occurs through an electronic control unit and wherein an undesired opening of the mold caused by any overpressure of the plastic material injected into the cavity of the mold is detected by means of transducers and corrected by means of the electronic control unit. The transducers are arranged outside the cavity of the mold.

A method and apparatus for injection molding of plastic material into a cavity of a mold by means of at least one injector whose opening and closing occurs through an electronic control unit and wherein an undesired opening of the mold caused by any overpressure of the plastic material injected into the cavity of the mold is detected by means of transducers and corrected by means of the electronic control unit. The transducers are arranged outside the cavity of the mold.

An injection molding cell is provided with an injection molding machine and its peripheral device and an injection molding cell management unit. The injection molding cell management unit includes a worker identification information input unit, configured to accept input of worker identification information for identifying a worker who performs input and/or operation of the injection molding machine and its peripheral device, and a prohibition state releasing unit configured to release a prohibition state of the input and/or operation of the injection molding machine and its peripheral device, based on the worker identification information.

An injection-molding system includes an extruding system configured to produce a mixture; a discharging channel communicable with the extruding system and including an outlet configured to discharge the mixture; and molding devices configured to receive the mixture. Each of the molding devices includes a hollow space, and a feeding port communicable with the hollow space and engageable with the outlet. An injection-molding method includes providing an extruding system configured to produce a mixture, a discharging channel including an outlet, and first and second molding devices; engaging the outlet with the first molding device; injecting the mixture into the first molding device; disengaging the outlet from the first molding device; moving the discharging channel away from the first molding device and toward the second molding device; engaging the outlet with the second molding device; injecting the mixture into the second molding device; and disengaging the outlet from the second molding device.

An injection-molding system includes an extruding system configured to produce a mixture; a discharging channel communicable with the extruding system and including an outlet configured to discharge the mixture; and molding devices configured to receive the mixture. Each of the molding devices includes a hollow space, and a feeding port communicable with the hollow space and engageable with the outlet. An injection-molding method includes providing an extruding system configured to produce a mixture, a discharging channel including an outlet, and first and second molding devices; engaging the outlet with the first molding device; injecting the mixture into the first molding device; disengaging the outlet from the first molding device; moving the discharging channel away from the first molding device and toward the second molding device; engaging the outlet with the second molding device; injecting the mixture into the second molding device; and disengaging the outlet from the second molding device.

An apparatus and method for eliminating mold lines when molding a part having ferromagnetic pigments is provided. A mold assembly having a mold with a cavity and valve gates is formed. Pucks are fitted at the gates to collect residual cold plastic. The calculation of a specific sequence and timing of the opening of the valve gates is determined based on a calculation of the total number of valve gates needed to fill a part while maintaining acceptable injection molding pressure. Once calculated, the gates are positioned around the mold cavity to balance flow length ratio. A primary gate is chosen for initial injection. The time for the material to flow from the first to the second gate is established. The second gate is opened after the flow front reaches the second gate. This pattern continues until all valve gates are opened.