The inner surface of the barrel is harder than the extr […]
The inner surface of the barrel is harder than the extruder screw barrel and its damage is later than the extruder screw. The scrapping of the barrel is such that the diameter of the inner diameter increases due to time wear.
The repair method is as follows:
1. The barrel with increased diameter due to wear. If there is a certain layer of nitrided, the inner hole of the barrel can be directly bored, ground to a new diameter, and then a new extruder screw is prepared according to this diameter. .
2. The inner diameter of the barrel is machined and trimmed to recast the alloy, the thickness is between 1~2mm, and then finished to the size.
3. Under normal circumstances, the homogenization section of the barrel wears faster. This section (take 5~7D long) can be trimmed by the boring, and then a nitriding alloy steel bushing is used. The diameter of the inner hole refers to the screw diameter of the extruder. , stay in the normal fit gap, processing and preparation.
[Small knowledge recommendation] Two important parts of the extruder screw and barrel, one is a slender threaded rod, and the other is a small and long diameter hole. Their machining and heat treatment processes are complicated and the precision is guaranteed. It is more difficult. Therefore, after the wear of these two parts is repaired or replaced with new ones, it must be comprehensively analyzed from an economic perspective.
If the repair cost is lower than the cost of replacing the extruder screw, it is decided that repair is not necessarily the correct choice. The comparison between the repair cost and the update cost is only one aspect.
Also depends on the ratio of repair costs to extruder screw time and renewal costs after repair and renewal of extruder screw usage time. It is economical to adopt a scheme with a small ratio and is the right choice.