A cooling apparatus for an extruder includes a supply line configured to receive bulk coolant from a supply circuit via an inlet. The supply line delivers supply coolant to the extruder along a flow path. A return line communicates expelled coolant from the extruder, and a circulation line connects the supply line to the return line. The circulation line supplies a recirculated portion of the expelled coolant to the supply line and mixes the bulk coolant with the recirculated portion of the expelled coolant forming the supply coolant. A bypass line connects the supply line to the return line, and a flow control valve connects one of the supply line and the return line to the bypass line. A proportion of the expelled coolant to the bulk coolant forming the supply coolant is adjusted by the flow control valve to control the temperature of the supply coolant.

A process for drying polymeric granular material (2) comprises the steps of: —introducing into said drying hopper (10) a process gas having a predefined flow rate so as to heat and dry the polymeric granular material, —discharging a portion of the heated polymeric granular material into a transformation unit (100) for the polymeric material; —loading an amount of fresh polymeric granular material (2a) into the drying hopper. The process gas flow rate is regulated by measuring the inlet temperature of the fresh polymeric granular material (2a) and comparing it with a predefined inlet temperature of the fresh polymeric granular material, on the basis of which the predefined process gas flow rate has been calculated. If the measured inlet temperature is different from the predefined inlet temperature, the flow rate of the process gas is regulated on the basis of the measured inlet temperature.

An extruder, such as a double-screw extruder includes a double cylinder and a double-lead screw arranged therein with a drive train for the screw. The drive train has a coupling with the screw. The extruder includes a sensor for recording a moment load having torque and/or bending moment and for generating electronic data from the recorded moment load. A controller is provided in operative connection to a drive for the drive train and the sensor is in data connection with the controller. The controller is adapted to evaluate the data on the recorded moment load and to trigger a protective action if a threshold value set in the controller is exceeded. The evaluation includes a bending moment calculation. A plastic molding plant produces a film with the extruder along with a nozzle unit and a cooling and wind-up unit or a compounding plant. A method for operating such a plant for manufacturing a film includes the extruder.

An extruder for polymeric materials, includes: a hollow extrusion cylinder, having an inlet for receiving pellets of polymeric material, and an outlet for expelling molten polymeric material; an extruder screw connected to a motor to rotate inside the extrusion cylinder and to move the polymeric material from the inlet to the outlet; heaters coupled to the extrusion cylinder; a sensor system configured to measure values of a recipe parameter and of a monitoring parameter; a processing unit, programmed to store a target value for the recipe parameter and to perform a feedback control to bring the recipe parameter to the target value and to keep it at the target value.

A method of cleaning a powder coating production line, the method including: providing a powder coating production line including equipment, an automatic cleaning tool, and a monitoring device; receiving, by the equipment, an instruction of automatic cleaning, and allowing the equipment to enter an automatic cleaning mode; cleaning, by the automatic cleaning tool, the equipment of the powder coating production line; monitoring, according to a preset monitoring condition and by the monitoring device, whether the automatic cleaning is completed; stopping the automatic cleaning when the monitoring device indicates the automatic cleaning has been completed, or continuing the automatic cleaning of the equipment; and turning off the automatic cleaning mode of the equipment.

The apparatus of the invention includes: an acquisition unit 101 that acquires input information including resin properties and acquires, as output information, a specified value of a physical quantity related to a kneaded resin or a kneading machine; a storage unit 16 that stores a knowledge file 162 containing correlations among the input information, the physical quantity and a plurality of screw configurations; and a search unit 106 and a configuration generator unit 107 together that infers, on the basis of the input information and the knowledge file 162, such a screw configuration that is able to meet the specified value.

A signal acquisition unit of an abnormality detection device for a twin-screw extrusion molding machine, when the twin-screw extrusion molding machine that melts and kneads a fed resin raw material is in operation, acquires an AE output of an AE sensor installed on a surface of a housing of the twin-screw extrusion molding machine. A determination unit determines whether an abnormality occurs in the twin-screw extrusion molding machine, based on a relationship between the AE output and a first threshold and a second threshold.

The apparatus of the invention includes: an acquisition unit 101 that acquires input information including resin properties and acquires, as output information, a specified value of a physical quantity related to a kneaded resin or a kneading machine; a storage unit 16 that stores a knowledge file 162 containing correlations among the input information, the physical quantity and a plurality of screw configurations; and a search unit 106 and a configuration generator unit 107 together that infers, on the basis of the input information and the knowledge file 162, such a screw configuration that is able to meet the specified value.

An apparatus (1) for optical inspection of a mass of polymeric material (2) passing through an extruder (3) having a hollow extrusion cylinder (4) extending elongately in a longitudinal direction comprises an optical sensor (8) which can be operatively coupled to the extrusion cylinder (4) and having an infrared light emitter (8a) and a receiver (8b) configured to measure a measurement parameter representing an optical property of the polymeric material (2) inside the extrusion cylinder (4) and is characterized in that it comprises a plurality of the optical sensors (8) which can be operatively coupled to the extrusion cylinder (4) in a plurality of measurement sites located in succession and spaced from each other along the longitudinal direction and a processor (9) programmed to acquire a plurality of measurement signals containing the measurement parameters measured by the corresponding optical sensors (8) and programmed to process the plurality of measurement signals in order to calculate a corresponding plurality of values of a control parameter indicating a physical state of the polymeric material (2) as a function of a longitudinal position.

Plasiticized polyvinylacetal films with greater film-to-film uniformity are produced by a process of extruding a melt stream containing a polyvinyl acetal and a plasticizer at 150-250 C., the film having a predefined melt viscosity at 60-170 C., by providing a first melt stream of at least a first plasticizer and a first polyvinyl acetal resin and measuring its melt viscosity at 60-170 C. online; and adjusting the 60-170 C. melt viscosity by adding a second plasticizer and/or a second polyvinyl acetal resin to the first melt stream in an amount to provide a second melt stream with a melt viscosity at 60-170 C. having a difference of at most 20% to the predefined melt viscosity at 60-170 C.