1. The degree of cross-linking (thermal extension) is unqualified

If the degree of cross-linking does not meet the standard, the thermal-mechanical properties of the cable are unqualified, Can not meet the requirements of operating temperature 90 ℃.

There are two main reasons for the unqualified crosslinking degree:

Unqualified formula: The type of compounding agent is not properly matched, and the formula should be adjusted to solve it;< /p>

Improper vulcanization process: such as low air pressure, fast line speed, high cooling water level, the solution The solution is to investigate the cause.

2. Unqualified structure and appearance

(1) The thinnest point of the insulating layer thickness is lower than the minimum value specified in the standard, or the average Thickness is lower than nominal. The reason for the unqualified insulation thickness is that the line speed is fast, the glue output of the extruder is small, and the mold selection is improper.

The solution is to reduce the line speed or extruder speed, and adjust the size of the die.

(2) Eccentric

The reason for the eccentricity is that the mold is not adjusted or the suspension control occurs after the recruitment is adjusted. Changes, the solution is to try to control the sag as stable as possible during driving.

3. Bamboo shape

The reason for the bamboo-like shape on the outside of the cable is the electrical and mechanical system. Unstable, the second is that the core is too small, or the outer diameter of the conductor is not uniform.

The troubleshooting method is to check the mechanical, electrical system and troubleshoot. Appropriately adjust the size of the core, control the outer diameter of the suburbs to be as uniform as possible, and the strands exceeding the technical requirements can be used.

4. Surface scratches

(1) The cable encounters the upper and lower walls or foreign objects in the vulcanized pipe. Therefore, it is required to adjust the degree of suspension, try to make the core move in the middle of the cross-linked tube, and clean it up in time if foreign objects are found.

(2) There is scorch on the outer edge of the mold sleeve. The solution is to adjust the temperature of the mold sleeve when starting the car to prevent overheating. Once burning is found, it should be stopped immediately to remove it, or it will not get better by itself.

5. Impurities

Most impurities in insulating materials and semi-insulating materials are added during mixing and extruder brought in during the process. During the operation, strict attention should be paid to the cleanliness of the materials to prevent the mixing of external impurities. Another impurity is scorch lump, its existence affects the performance and service life of the cable, so strictly control the temperature during mixing and extrusion to prevent the occurrence of scorch.

6. Bubble

Bubble in insulation can occur for two reasons. One is caused by extrusion. The solution is to select the appropriate mold. There are bubbles in the shielding layer. The main reason is that there is moisture in the material, and it should be dried before extrusion. Second, the cooling is not sufficient. At this time, the following will appear. A circle of bubbles appears on the circumference equidistant from the wire core. The method of elimination is to strengthen the cooling, increase the water level and reduce the temperature of the cooling water.