There will be cracks on the surface of the composite pipe. The cracks are often caused by various factors. The improper operation in the general production process and the influence of the external environment will cause the cracks to affect the use of the pipe. Let us analyze the causes of cracks.
1. The rolled part of the composite pipe before the finished product has ears; ears, flashes, severe scratches, and severe wear of the roller grooves during the rolling process; improper cleaning of the billet with serious defects.
2. During rolling, there are inclusions in the molten iron, and the oxygen content is high, which generates oxides, which are not cleaned during the manufacturing process, resulting in cracks.
3. The molten iron contains a large amount of gas. When the molten iron is solidified, the gas is discharged to form bubbles. The bubbles near the outer layer of the slab become subcutaneous bubbles, which are arranged vertically in a honeycomb shape under the surface of the slab. Generally, the bubbles generated after the billet is rolled can be welded, but some subcutaneous bubbles are closer to the surface. When heating, when the surface of the billet is oxidized or burned, the subcutaneous bubbles will be exposed and oxidized, making it impossible to weld. Close, so that the hole composite pipe cracks.
The above is an introduction to the causes of cracks on the surface of composite pipes. In fact, the occurrence of cracks can be avoided by some methods. In the process of production and processing, everyone must pay attention to the correct grasp of the method to avoid the occurrence of air bubbles during processing, so that cracks can be prevented.