FAQs about restored bimetallic screw barrel

In order to improve production efficiency and reduce production costs, some plastic manufacturers often purchase new barrel and screw, in fact, restored bimetallic screw barrel is durable as well. 

1. What is the abradant degree of barrel and screw ? 

The abradant degree of each set of bimetallic screw barrel is different. In general, the abradant degree of the screw is larger. If the materials' hardness of the screw is far more than the barrel, then the bimetallic barrel will be more abradant. 

2. Why should bimetallic screw barrel be nitriding treated ?

When the screw is abradant, the bimetallic barrel is also worn. If there is a nitride layer, the bimetallic screw barrel can be used for at least half year after the first restoring. For the second restoring, there will be no nitride layer, no use. So the nitriding treatment is the key factor of service life of bimetallic screw barrel. 

3. How to identify whether the bimetallic screw barrel is nitriding t treated ?

After nitriding treatment, the bimetallic screw barrel will become gray, which is different from the original color. A barrel can be subjected to four times of nitriding treatment at most. Because the iron in the barrel is denatured, the structure has changed. If the bimetallic screw barrel is nitriding treated with quality alloy, it can be used for at least two years. 

4. Restoring old bimetallic barrel with new screw? 

If you are a renewable materials factory, there is no difference between restoring old bimetallic barrel and manufacturing new bimetallic barrel. Because the screw made from imported alloy which is very wear-resistant. It is better to use old barrel with a new screw. The performance will be the same and you can save half cost!