When producing profiles and tubes with internal hollow chamber structures, so-called supporting air is often used. Here, a volume of air is blown through the die into the interior of the hollow chambers or lumens so that they do not collapse. The outer surfaces of the extrudates are usually drawn […]
Troubleshooting
9 posts
Blocking of films is the most frequent cause of complaints about films. In some light cases, the problem is only a slight quality defect, but in more extreme cases it leads to large quantities of rejects, as entire rolls have to be disposed of on which blocking has occurred. […]
When extruding profiles, the maximum production speed is one of the most important factors for the calculation af a quotation. If the production speed is assumed to be higher than the real production can be in practice, this can mean high losses for the extrusion plant and represents a high […]
Voids/blowholes/vacuoles are frequent quality problems that can occur especially in the manufacture of thick-walled products. Although the cause of this problem is well known, it is often difficult and time-consuming to avoid it. When cooling plastics from melt temperature to ambient temperature, the specific volume or density of the plastic […]
In extrusion, the temperature distribution inside the product is a very relevant value whose knowledge can contribute to understanding a variety of effects or problems. However, measuring the internal temperature of an extruded product is difficult in most cases, because in a continuous process such as extrusion (with sometimes very […]
In different extrusion processes, curvature (or bowing, sabre-running, katana effect, etc.) represents a major quality problem and is often difficult to get a grip on. The cause of the curvature is almost always an inhomogeneous thermal situation of the product during cooling and can often be greatly reduced or completely […]
10 possible causes for die drool and solution approaches The formation of die drool during extrusion is a frequently occurring problem whose development cannot yet be clearly explained to this day. Die drool formation refers to deposits in the area of the nozzle exit, which are initially perceived as a […]
Identifying the “real” cause of a problem is usually the most important step if a sustainable solution is to be achieved. Often fundamental mistakes are made in this area and either “workarounds” are developed which merely help to avoid the problem or fake causes are eliminated. Various methods exist for […]
The extrusion of pipes, profiles, sheets, films, solid and hollow rods or other semi-finished products can cause a wide variety of problems that can impair the economic efficiency of the processes. These problems may concern the production itself, but may also have arisen from the market or external circumstances. We […]