The invention relates to a monitoring method for monitoring a film bubble (FB) in a discharge region (112) downstream of a discharge nozzle (110) of a blown film device (100), comprising the following steps: optically detecting at least one contour parameter (KP) of a film contour (FK) of the film bubble (FB) in the discharge region (112), comparing the at least one detected contour parameter (KP) with a specific preset value (VW), determining a contour deviation (KA) between the at least one detected contour parameter (KP) and the specific preset value (VW), outputting the contour deviation (KA) as monitoring result (UE).

In blown film installations, it is known to provide longitudinal stretching of the produced double layer film strip downstream of the draw-off, more precisely downstream of the reversing unit and upstream of the winder. It is also known to stretch the down-drawn film, wherein the film must then be preheated owing to the long cooling path from the draw-off. According to a first feature, the present invention specifies warming the film above the draw-off and then treating it mechanically. The film can thereby be brought with only little energy from a first level of warmth to a temperature level at which it can easily be worked. According to a second feature, the invention specifies providing a tractive force breakdown brake.

The invention relates to an extrusion device and an extrusion method for the extrusion of plastic profiles, in particular a nozzle plate, comprising at least one flow channel for plastic melt. At least one wall region of the flow channel can be temperature controlled in a targeted manner with a local temperature control device for setting the flow speed of the plastic melt.

A method of forming a confined crystallization multilayer film includes coextruding a plurality of first polymer layers and a plurality of second polymer layer to form a multilayer film wherein each first polymer layer is sandwiched between second polymer layers and axially orienting the multilayer film at a temperature below the melting temperature (T.sub.m) of the second polymer layer and to a thickness such that each first polymer layer forms a high aspect ratio substantially crystalline lamellae.

Pipe corrugators having opposed series of pushed mold blocks forming a moving mold tunnel are subject to significant thermal expansion and are designed with a thermal expansion gap. The present invention provides a method and apparatus for measuring changes in this expansion gap and preferably recognizing potential thermal issues before serious problems occur. A sensor is provided adjacent a mold block drive that preferably detects a time duration between sensing a trailing portion of a lead mold block and a leading edge of a following mold block separated from the lead mold block by the thermal expansion gap. This time duration in combination with a speed of the pushed mold blocks is used to calculate the size of the thermal expansion gap.

A method is disclosed for determining at least one geometric parameter of an object comprising a molten component. The method includes determining a relationship between a refractive index of the object and a shrinkage occurring during a solidification of the object. The refractive index and at least one geometric parameter of the object comprising the molten component is determined using a measuring apparatus. At least one geometric parameter of the solidified object from the refractive index and the at least one geometric parameter of the object comprising the molten component is determined using the measuring apparatus and taking into account the determined relationship between the refractive index of the object and the shrinkage occurring during the solidification of the object.

A method for manufacturing a cylindrical honeycomb fired body including: preparing a cylindrical honeycomb formed body; obtaining a cylindrical honeycomb dried body by drying the cylindrical honeycomb formed body; calculating predetermined parameters (E.sub.AVE1, E.sub.AVE2, E.sub.AVE3 and E.sub.AVE4) from average values of distance between a center of gravity position O and an outer peripheral contour in a plurality of predetermined angle ranges; specifying a minimum value of the predetermined parameters; obtaining a cylindrical honeycomb fired body by placing the cylindrical honeycomb dried body on a shelf plate and firing it while passing it through a continuous firing furnace, such that the direction in which the cells of the cylindrical honeycomb dried body extend vertically, and a particular location on the outer peripheral side surface determined according to the minimum value is positioned at the front.

A die attached to a head of a rubber extrusion device is disposed at a leading end position of an extrusion flow path. The die is moved at least in a uniaxial direction relative to the head along a leading end surface of the head to place the die and the head in a desired relative position. A rubber material is extruded forward using a screw installed inside a cylinder, while being mixed and kneaded. Resultant unvulcanized rubber is fed into an extrusion flow path and extruded from an extrusion port formed in the die.

A device for centering an extrusion die for extruding an extrusion material wherein the device includes a housing means on or in which one or more centering elements are arranged or formed, wherein the one or more centering elements are configured to exert a centering force on an extrusion die to be centered, wherein the housing means comprises one or more fastening interfaces, by means of which the housing means can be fastened to an extrusion die to be centered or to an extrusion means comprising an extrusion die to be centered.

A method for determining sagging of melt of a tube extruded in an extrusion device includes structuring a measuring device to rotate about the tube. The measuring device is configured to measure a wall thickness of the tube over a circumference of the tube and determine a wall-thickness profile over the circumference of the tube from the measured wall thicknesses. The wall-thickness profile includes a frequency and an amplitude. The method further includes determining a sagging of the melt from at least one of (i) the frequency and (ii) the amplitude of the wall-thickness profile.