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.

A control system and a control method of manufacturing injection molding products are provided. The control system includes an injection molding machine, an information input interface, a computing server and a data conversion device. At first, product information is inputted through the information input interface. The product information is transmitted to the computing server, and then the computing server determines injection molding parameters according to the product information. The injection molding parameters are transmitted to the information input interface. After data conversion through the data conversion device, the injection molding machine is controlled to manufacture the injection molding products according to the converted injection molding parameters.

A plasticizing device includes a first member having a groove portion that has a spiral shape extending to a center, a motor that rotates the first member, a second member that faces the first member, and a heating unit for heating a material that is transported along the groove portion, the first member having a plurality of recessed portions on a bottom surface of the groove portion. By providing a plurality of recessed portions on the bottom surface of the first member through which the material flows, the rotational force of the rotating first member is easily transmitted to the material and the amount of material flowing in the first member can be increased.

An injection molding apparatus has a mold tool that is positioned around a field joint of a pipeline to define a mold cavity. Two or more pumping chambers communicate with the mold tool. Each chamber is expansible to draw in molten polymer and contractible to drive the polymer into the mold cavity. Expansion of one chamber is synchronized with contraction of another chamber. The operation of supply and injection valves associated with the chambers is also synchronized, both with each other and with expansion and contraction of the chambers. In the embodiment described, two pumping chambers are defined within a common pressurizing cylinder, in which the chambers are separated by a piston. The piston is movable within the cylinder to determine and to synchronize expansion and contraction of the chambers.

In one aspect, there is provided an injection molding system configured to operate in a plurality of cycles. The system comprises, amongst other things, a controller that is configured for performing a comparison of a variable pressure setpoint with a target pressure value. The controller is configured to, when the target pressure value is less than the variable pressure setpoint by at least a predetermined lower bound, (i) decrease the variable pressure setpoint to a reduced variable pressure setpoint and (ii) not further decrease the variable pressure setpoint from the reduced variable pressure setpoint until the pump assembly operates for a plurality of stabilizing cycles at the reduced variable pressure setpoint.

In one aspect, there is provided an injection molding system configured to operate in a plurality of cycles. The system comprises, amongst other things, a controller that is configured for performing a comparison of a variable pressure setpoint with a target pressure value. The controller is configured to, when the target pressure value is less than the variable pressure setpoint by at least a predetermined lower bound, (i) decrease the variable pressure setpoint to a reduced variable pressure setpoint and (ii) not further decrease the variable pressure setpoint from the reduced variable pressure setpoint until the pump assembly operates for a plurality of stabilizing cycles at the reduced variable pressure setpoint.

The invention relates to an apparatus (1) for injection molding, said apparatus comprising -a mold cavity member (20) having a mold cavity (22), -a melt channel, -an injection chamber (16) and -an injection gate having an injection gate hole (24). The apparatus further comprises a movable injection sleeve (10) and furthermore -the melt channel is configured for providing a flow of molten material from a source of molten material to an injection chamber (16), -the apparatus (1) is configured for transferring the molten material from the injection chamber (16) to the mold cavity (22) via said injection gate hole (24), said injection gate being controllable by a forward part of a movable filling valve (6), and -the injection chamber (16) has a volume that is controllable by movement of the movable injection sleeve (10). The invention further relates to a method of injection molding.

A strain gauge nozzle adapter that may be placed between a barrel end cap and a nozzle body of an injection molding system, the strain gauge nozzle adapter having a strain gauge pin that measures strain within the strain gauge nozzle adapter for use in approximating conditions within an injection molding system, such as pressure or the location of a melt flow front. The strain gauge nozzle adapter may include a plurality of strain gauge pins. An alternative material insert in the strain gauge nozzle adapter may surround a strain gauge pin to amplify meaningful measurements obtained by the strain gauge pin so that noise measurements do not compromise the accuracy of approximation of conditions within a mold.

A control system and a control method of manufacturing injection molding products are provided. The control system includes an injection molding machine, an information input interface, a computing server and a data conversion device. At first, product information is inputted through the information input interface. The product information is transmitted to the computing server, and then the computing server determines injection molding parameters according to the product information. The injection molding parameters are transmitted to the information input interface. After data conversion through the data conversion device, the injection molding machine is controlled to manufacture the injection molding products according to the converted injection molding parameters.

A method of forming a hollow article includes injecting a first molding material into a first mold cavity at a first injection pressure to form a first molded shell and injecting a second molding material into a second mold cavity at a second injection pressure to form a second molded shell. The first molded shell has a first peripheral edge, and the second molded shell has a second peripheral edge. The method includes positioning the first shell and second shell into facing relation with the first and second peripheral edges in a third cavity, and injecting a third molding material into the third cavity at a third injection pressure to bond together the first and second shells along the first and second peripheral edges to form the hollow article. The third injection pressure is less than the first injection pressure by at least about 3.5 bar.