A method and apparatus for producing hollow articles made of injection moulded plastic material by a mould having a die within which there is inserted a core, and at least one injector including a pin valve displaceable between a closing position and an opening position for injecting the pressurized plastic material into a space comprised between the die and the core. During the injection, any flexural deflection of the core is detected and the pin valve of the or of each injector is displaced in a controlled fashion to adjust a pressure and a flow rate of the injected plastic material, so as to reduce or eliminate such deflection of the core.

A method of injection molding plastic material in granular form includes providing an injection molding press; a dehumidification system including a hopper for containing the granular material; and a dry air generator connected to the hopper. The type of plastic material and mass of plastic material processed by the press are set in an electronic control unit, which regulates the dry airflow rate. The plastic material is injection molded and dry airflow is generated through the hopper. The dry air flow rate is regulated in proportion to the flow rate of plastic material processed by the press. The duration of the molding cycle in progress is detected and the flow rate of plastic material processed is calculated using: duration of the molding cycle in progress, mass of plastic material processed by the press in a molding cycle(s). Injection molding and dehumidification systems process plastic material.

Non-time dependent calculated variables based on measured strain are used to effectively determine an optimal hold profile for an expanding crosslinking polymer part in a mold cavity. A system and/or approach may first inject molten expanding crosslinking polymer into a mold cavity, then measure strain at the mold cavity or at another location within the injection molding system, and then calculate at least one non-time dependent variable during an injection molding cycle. Next, the system and/or method commences a hold profile for the part, and upon completing the hold profile, the part is ejected from the mold cavity, whereupon a cure profile is commenced.

A melt temperature sensing kit includes a housing and a cup. The housing defines a cavity and has an outer periphery configured to be received by a platen of an injection molding machine. The cup has a proximate end and a distal end and is configured to be received within at least a portion of the cavity. The cup includes a base enclosing the distal end of the cup and a sidewall extending from the base, the sidewall defining a first aperture at the proximate end of the cup, a second aperture disposed between the proximate end and the distal end of the cup, and an internal volume. The first aperture, the second aperture, and the internal volume cooperate to define a flow path. At least one of the housing and the cup facilitate measurement of a shot flow temperature as part of a melt temperature measurement process.

Non-time dependent measured variables are used to effectively determine an optimal hold profile for an expanding crosslinking polymer part in a mold cavity. A system and/or approach may first inject molten expanding crosslinking polymer into a mold cavity, then measure at least one non-time dependent variable during an injection molding cycle. Next, the system and/or method commences a hold profile for the part, and upon completing the hold profile, the part is ejected from the mold cavity.

Non-time dependent measured variables are used to effectively determine an optimal hold profile for an expanding crosslinking polymer part in a mold cavity. A system and/or approach may first inject molten expanding crosslinking polymer into a mold cavity, then measure at least one non-time dependent variable during an injection molding cycle. Next, the system and/or method commences a hold profile for the part, and upon completing the hold profile, the part is ejected from the mold cavity, whereupon a cure profile is commenced.

A method for determining positions of a real moulding material front during a process to be carried out with a moulding machine, wherein a simulation progression (SV) of a variable characteristic of the process is calculated, positions of a simulated moulding material front are determined from the simulation, the real process is carried out, and at least one measurement progression (MV) of the at least one characteristic variable is measured directly or indirectly, a transformation is chosen, which has at least one parameter (?V, kp, V.sub.unknown), the transformation is applied to the at least one simulation progression (SV), with the result that a transformed simulation progression (tSV) is formed, and a parameter value is determined for the parameter (?V, kp, V.sub.unknown) such that a deviation between the measurement progression (MV) and the transformed simulation progression (tSV) is minimized according to a predetermined error measure or according to an operator input.

An injection molding machine includes a plasticizing unit having a plasticizing cylinder and a material-conveying device that is movable in the plasticizing cylinder and powered by a material-conveying drive, a material-conveying drive control, which is coupled with the material-conveying drive and is designed to control operating parameters of the material-conveying drive, a closing unit having an injection molding tool that is connected with an outlet nozzle of the plasticizing cylinder, as well as a closing unit control, which is coupled with a closing unit drive of the closing unit and is designed to control operating parameters of the closing unit drive. The injection molding machine further includes one or more dieletric or acoustic sensors which are disposed in the cavity of the injection molding tool or close to the cavity of the injection molding tool and are designed to determine the dielectric polarizability, mobility of free load carriers and/or acoustic material responses of a molding material in the cavity of the injection molding tool. A sensor control is coupled with the dielectric or acoustic sensor(s) and is designed to ascertain a time-dependent degree of crystallization and a time-dependent median temperature of the molding material in the cavity of the injection molding tool from the dielectric polarizability, mobility of free load carriers and/or acoustic material responses determined by the dielectric sensor(s) and, depending on the ascertained degree of crystallization and the ascertained median temperature, to actuate the material-conveying drive control and/or the closing unit control to adjust the operating parameters of the material-conveying drive and/or of the closing unit drive.

Disclosed is a method of adjusting a motion profile of a shooting pot plunger for use in a molding system, the shooting pot plunger slidably movable within a shooting pot cavity, the method comprising: sensing a characteristic at a predetermined location in an injection circuit of the molding system; determining that the sensed characteristic is outside of a threshold range; adjusting the motion profile of the shooting pot plunger to account for determining that the sensed characteristic is outside of the threshold range; and storing the adjusted motion profile in a memory.

The present disclosure relates to machines and methods for reaction injection molding. In particular, the present disclosure provides small format reaction injection molding machines having exchangeable molds and reactant material tanks, as well as molds configured for use therein and associated componentry.