In order to achieve high product quality and process reliability in a process for manufacturing an endless profile strand of soft plastic and/or rubber material fed to a supply storage for a sealing profile, edge protection profile or the like on a motor vehicle, it is provided that the manufacturing process be divided into two process sections which are carried out on two manufacturing lines that can be operated independently of one another.

A method of extruding a melt of a linear low-density polyethylene (LLDPE) without surface melt fracture, the method comprises heating a melt of the LLDPE to a temperature from 190.0 to 260.0 degrees Celsius; and extruding through a die the heated melt at a shear rate of from 1,100 to 7,000 per second and at a shear stress of greater than 0.40 megapascal, thereby forming a polyethylene extrudate without surface melt fracture.

A method for detecting irregularities on a material strand made of an elastomeric material comprises the steps of: (a) providing a material strand which defines a longitudinal axis along which the material strand is to be conveyed; (b) bringing a detection element in contact with the material strand, wherein at least one of the detection element being movably mounted in a direction of deflection transverse to the longitudinal axis and a force can act on the detection element in a force direction, (c) setting up a relative movement between the detection element and the material strand along the longitudinal axis; and (d) detecting at least one of a deflection of the detection element in the deflection direction and a force acting on the detection element in the force direction, so as to detect irregularities in the material strand.

In order to achieve high product quality and process reliability in a process for manufacturing an endless profile strand of soft plastic and/or rubber material fed to a supply storage for a sealing profile, edge protection profile or the like on a motor vehicle, it is provided that the manufacturing process be divided into two process sections which are carried out on two manufacturing lines that can be operated independently of one another.

Provided is a kneading device that can check a progress of wear of an inner wall face of a kneading chamber provided in a casing without stopping the kneading device. A kneading device includes a sensor-mount space provided in a wall of a casing, a wear detecting sensor of which a detecting section is disposed at a bottom of the sensor-mount space, and a controller that receives a signal output from the wear detecting sensor, the controller including a wear determining unit that determines that wear of an inner wall face of a kneading chamber has progressed based on a change in the signal.

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.

A method of manufacturing a material strand (100), particularly for sealing, trimming or fastening of doors (11) or windows (12) of a motor vehicle (10), comprises the steps of: a) extrusion of an extruded strand (200); b) testing the extruded strand (200) after the extrusion, thereby identifying first segments (210) comprising manufacturing defects (211) and second segments (220) being free from manufacturing detects; c) cutting out the first segments (210) from the extruded strand (200), thereby causing faces (222) at the second segments (220); d) joining cut faces (222) of second segments (220) to obtain a joint (102) and to form a material strand (100), the joint (102) having a position within the material strand (100), wherein a minimum distance (d) is maintained between the positions of adjacent joints (102); e) identifying the position of each joint (102); and f) forming a transport unit (110) having a predetermined maximum length by winding the material strand (100).

A method for manufacturing a material strand assembly for a vehicle. The method includes: extruding strand material in an extruder so that an extruded material strand is produced; monitoring the quality of the extruded material strand so as to detect faults of the extruded material strand; in case of a detection of a fault, cutting out the fault from the material strand and re-joining cutting end faces, thus producing a joint, so that a faultless material strand is produced. The cutting-out step is conducted such that any two adjacent joints are at a minimum joint distance from each other. The faultless material strand is stored in a storage unit so as to produce the material strand assembly. The extruded material strand is passed through a first strand accumulator between the extruder and the cutting arrangement and through a second strand accumulator between the cutting arrangement and the storage unit.

A method of manufacturing a material strand (100), particularly for sealing, trimming or fastening of doors (11) or windows (12) of a motor vehicle (10), comprises the steps of: a) extrusion of an extruded strand (200); b) testing the extruded strand (200) after the extrusion, thereby identifying first segments (210) comprising manufacturing defects (211) and second segments (220) being free from manufacturing detects; c) cutting out the first segments (210) from the extruded strand (200), thereby causing faces (222) at the second segments (220); d) joining cut faces (222) of second segments (220) to obtain a joint (102) and to form a material strand (100), the joint (102) having a position within the material strand (100), wherein a minimum distance (d) is maintained between the positions of adjacent joints (102); e) identifying the position of each joint (102); and f) forming a transport unit (110) having a predetermined maximum length by winding the material strand (100).

The invention relates to the determination of the optical quality of a film. On the one hand, a correlation of the obtained measured values with the production parameters, which are detected in a time-synchronous manner at the extrusion plant, is carried out. On the other hand, a correlation of said obtained measurement data with the geometric and/or functional properties of a film, for example the water vapor permeability, is carried out. The obtained correlation of data is used in the process for controlling the running production process of the film to an optimum operating point. Consequently, the resulting functional properties of a film are improved in an automated manner and met according to the desired specifications. The operator can predetermine which geometric and/or functional properties of a film are accepted as a control variable.