Three Common Ways to Clean the Screw of A Twin-screw Extruder

The superior performance and customizability of the twin-screw extruder are its characteristics in this position. While a variety of additives and fillers can be treated and extruded, some methods of obtaining these products can lead to contamination problems and low flow or pressure in many parts throughout the barrel.

Cleaning in extrusion is often more challenging than other processes, and twin-screw extruders face greater challenges because the system is more complex than single-screw extruders.

Let's take a look at what cleaning methods are available for twin-screw extruders.

Resin Cleaning

Polyester resin or epoxy resin are generally used in the new equipment to clear the machine or extruder after a period of time. You can use this method when there are some materials residue in the screw and barrel and getting gelation, leading to the extrusion speed becoming slower.

The first step in cleaning the screw is to turn off the charging insert, it means close the hopper bottom discharge port; then turn down the screw speed to 15-25 r/min and maintain this speed until the melt flow stops at the front of the die head. All heating zones of the barrel should be set at 200°C. As soon as the barrel reaches this temperature, start cleaning.

Fire Roasting Cleaning

It’s the most common and effective way to use the fire to remove the plastic stick to the screw. Use the torch cleaning immediately after the use of the screw, because the screw has the heat at this time and the heat distributed evenly on the screw. However, acetylene flame should never be used to clean the screw. Acetylene flame temperature can up to 3000 °C. Using acetylene flame to clean the screw will not only destroy the metal characteristics of the screw, but also will significantly affect the mechanical tolerances of the screw.

Water cleaning

Automatic screw washing machine uses the kinetic energy of hydrodynamic rotation, with the reaction force of screw rotation to achieve 360 degrees without dead angle stripping. This cleaning method has high efficiency and will not break up the physical structure of the screw, to achieve a new technology of screw cleaning in an environment-friendly, efficient and energy-saving way. It is suitable for the forced stripping and removal of many kinds of polymer materials, so it is a green processing process with good cleaning performance. PVC Pipe Production Line, PVC Granulator, PVC Pipe Making Machine , PVC Profile Making Machine, PVC Extruder Machine.