Why and How to Purge Extruders

 

It is not certainly new to use purging compounds to remove another material from extruders. However, it is wise to know the reasons why one needs to use a Purging Compound for Extruders to clean extruders. It is also wise to know how to effectively clean extruders using the best quality purging compound.

Let us have a look at the few reasons to purge extruders before knowing how to purge extruders.

Reasons to Purge Extruders

There are various reasons to purge extruders, and we have noted a few of those.

One significant justification for purging an extruder is to eliminate one material with one more to save the cost of dismantling, cleaning, and fitting the extrusion framework for example screw, adaptor, die, and so forth.

It is not the only reason to purge extruders. There are a few more.

One more justification for purging an extruder is to eliminate a high melting resin, for example, nylon 66 with a lower melting polymer like nylon 6 so the extruder can be closed down at a lower temperature and subsequently limit degradation of both thermal and oxidative. Moreover, it will be simpler to restart a full machine.

Purging may also be likewise required to eliminate chemically or thermally unsteady resins from the extruder so a cast acrylic or other cleanse compound can have used to clean the extruder.

How to Select the Purging Material 

While selecting the Purging Material for Extruder it is wise to select one of the same family as the resin in the extruder. Like you can select 2GT and 4GT polyester or HDPE and LDPE. Another aspect to consider is that the melting viscosity of the purging material and the resin is in the same range. It is also wise to notice if the new material is of a different colour. If it is it needs to be darker than the earlier one. This helps to prevent having die and weld lines on the extrudate.

How to Purge Extruders

Now you know why to purge extruders and how to select the ideal purging material. Now is the time to know the ideal way to purge.

There are a few steps to follow to ideally purge extruders. Let us have a look at those.

Temperature to Maintain

You need to keep the temperature of the die 20 to 30 degrees higher than that of the cylinder. You need to be cautious with resins which can easily get thermal decomposition or carbonization. Such can happen if the resin is PVC, POM, or PA.

The Rotation Speed of the Screw

It is wise to change the screw speed from low to high a few times. If the extruder has a feeder, it is best to fill the cylinder with resin. You can do this by increasing the feed amount and lowering the rotation speed.

Wait Time

You need to keep the Purging Compound for Extruders of reputed make inside the extruder for 5 to 10 minutes. This will help the compound to bond with the resin which is inside the extruder.

Removal of Screen Mesh 

There will not be any necessity to change the screen mesh.

If you have purchased a Purging Material for Extruder from UNICLEANPLUS then it is for sure the quality will best. Call them at +91 9021232809 to place your order.