An extrusion apparatus includes a diagnostic system with a material processing section and an extruder screw disposed for rotation in a barrel and surrounded by a shroud assembly. The apparatus includes a temperature control system with heater sand cooler. The apparatus includes a speed control apparatus that has a drive unit and a speed variation device that is coupled to the extruder screw. The apparatus includes a diagnostic system in communication with the material processing section and/or the speed control apparatus. The diagnostic system includes a sensor system in communication with the material processing section and/or the speed control apparatus; and a computer processor in communication with the sensor system and a computer. The computer processor includes a computer readable medium that employs one or more algorithms and that are executable by the computer to generate signals characterizing performance of the material processing section and/or the speed control apparatus.

Extrusion techniques for reducing bow of an extrudate formed from a ceramic forming mixture. Velocities of an outer surface of the extrudate are measured at a plurality of peripherally spaced measurement locations. The velocities are compared to determine whether there is a velocity bias, and the comparison is used to selectively alter the flow of the ceramic forming mixture.

The smoothing device for plastic films comprises plastic-melt-producing means (1, 5), an adjustable slit die (10) and a roller smoothing unit (16) having cooled smoothing rollers (11, 12), which form an adjustable smoothing gap (13) between each other. Optionally, further rollers (15) are arranged downstream. A thickness gauge (23) measures the thickness of the plastic-film web (22). A controller (30) for controlling the thickness of the plastic-film web (22) may set a setpoint thickness (SD) of the plastic-film web (22) and the volumetric flow rate (SS) of the plastic melt or the line speed (LS). The controller (30) captures the current torques and rotational speeds of the rollers (11, 12, 15) and the current thickness (FD, FD1-FDn) of the plastic-film web (22).

The controller (30) sends setpoint rotational speed signals (C0S, C2S-CnS, CAS) calculated from the captured torques of the rollers (11, 12, 15) to the drives of the rollers and a smoothing-gap setpoint distance signal (GW) for adjusting the smoothing gap (13), and furthermore—in the case of a specified line speed (LS)—setpoint plastic-melt volumetric flow rate signals (SS) to the plastic-melt-producing means, or—in the case of a specified plastic-melt volumetric flow rate (SS)—setpoint line speed signals (LS) to the drives of the rollers (12).

A method is disclosed for die coating a moving substrate with a high viscosity material such as a polymer. The method includes heating and mixing ingredients to form a homogenous mixture, pumping the mixture around a circulation loop with a first pump, maintaining a predetermined pressure of the mixture within the circulation loop, drawing mixture from the circulation loop with a second pump, delivering the mixture using the second pump to an extrusion die adjacent the moving substrate to coat the substrate, and controlling the second pump as a function of at least the speed of the moving substrate to maintain predetermined characteristics of the coating mixture applied to the moving substrate. An apparatus for carrying out the method also is disclosed.

An extrusion apparatus includes a diagnostic system with a material processing section and an extruder screw disposed for rotation in a barrel and surrounded by a shroud assembly. The apparatus includes a temperature control system with heater sand cooler. The apparatus includes a speed control apparatus that has a drive unit and a speed variation device that is coupled to the extruder screw. The apparatus includes a diagnostic system in communication with the material processing section and/or the speed control apparatus. The diagnostic system includes a sensor system in communication with the material processing section and/or the speed control apparatus; and a computer processor in communication with the sensor system and a computer. The computer processor includes a computer readable medium that employs one or more algorithms and that are executable by the computer to generate signals characterizing performance of the material processing section and/or the speed control apparatus

A plastic film of a thermoplastic synthetic resin is made in a film-making system by extrusion from a die of an extruder. First the plastic is melted and extruded from the die as a tube or web that is, typically after cooling and stretching, formed into a package. At least one reference parameter is provided, and, during continuous operation of the system, two input parameters different from the reference parameter are measured by respective measuring devices An output is determined from these reference parameters and is compared with the reference parameter.

A method is disclosed for die coating a moving substrate with a high viscosity material such as a polymer. The method includes heating and mixing ingredients to form a homogenous mixture, pumping the mixture around a circulation loop with a first pump, maintaining a predetermined pressure of the mixture within the circulation loop, drawing mixture from the circulation loop with a second pump, delivering the mixture using the second pump to an extrusion die adjacent the moving substrate to coat the substrate, and controlling the second pump as a function of at least the speed of the moving substrate to maintain predetermined characteristics of the coating mixture applied to the moving substrate. An apparatus for carrying out the method also is disclosed.

A method of manufacturing a polymer film includes melting a resin, extruding the melted resin through a die to produce a polymer film, shaping the polymer film, cooling the polymer film, capturing an image of a test pattern through the polymer film, calculating a modulation transfer function value from the image, and adjusting a process parameter of the melting, the extruding, the shaping, or the cooling based on the calculated modulation transfer function value.

The present invention relates to a polyethylene resin composition for lamination having excellent adhesiveness to a substrate or the like, and preferably also excellent in easy-opening properties such as easy piercing properties, and more specifically, relates to a polyethylene resin composition (C) for lamination containing an ethylene/propylene copolymer (A) having the following properties (a-1) to (a-4).

(a-1) A constituent unit derived from ethylene is contained 80 to 98 mol % as a main component, a constituent unit derived from propylene is contained 2 to 20 mol % as an essential sub-component, and a constituent unit derived from a third -olefin other than ethylene and propylene may be contained 5 mol % or less as a sub-component.

(a-2) MFR 0.1 to 100 g/10 min.

(a-3) Density is 0.88 to 0.94 g/cm.sup.3.

(a-4) Total of vinyl and vinylidene is 0.35 or more.

The invention relates to a method and a device for producing a circular-cylindrical body (4) which consists of a plastic compound and which has at least one helical inner recess that runs in the interior of the body. The method has the following steps: producing a circular-cylindrical body (4), which consists of a plastic compound and which has at least one linear inner recess that runs in the interior of the body, by means of an extrusion molding die (1), discharging the circular-cylindrical body (4) out of the extrusion molding die (1) via a twisting section (7) onto a holding and transporting device (2) which is designed to hold and transport the circular-cylindrical body (4) and which can be rotated about the longitudinal axis of the holding and transporting device, twisting the circular-cylindrical body (4) on the twisting section (7) in order to form the at least one helical inner recess by rotating the holding and transporting device (2) together with the circular-cylindrical body being held and transported in the holding and transporting device, and discharging the circular-cylindrical body (4), which has at least one helical inner recess running in the interior of the body, out of the holding and transporting device (2) onto a storage device (3).