The degree of crosslinking (hot extension) is unqualified
If the degree of cross-linking fails to meet the standard, the thermal-mechanical properties of the aac cable are unqualified and cannot meet the requirement of 90°C working temperature.
The reasons for the unqualified cross-linking degree are the unqualified formula and the improper type and ratio of the compounding agent. The formula should be adjusted to solve the problem; the second is the improper vulcanization process, such as low air pressure, fast line speed, high cooling water level and other factors.
The solution is to first find out what is the reason, which may be one or several reasons at the same time, and eliminate the reasons.
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 the nominal value. The reasons for the unqualified insulation thickness are the fast line speed, the small amount of glue from the extruder, and the improper selection of molds.
The solution is to reduce the linear speed or increase the speed of the extruder and adjust the size of the die.
The reason for the eccentricity is that the mold is not adjusted or the suspension control has changed after the recruitment is adjusted.
The solution is to control the drape as stable as possible during driving.
The reason for the appearance of the bamboo-shaped outside of the cable is electrical and mechanical systems that cause the traction speed to be unstable. The second is that the core is too small, or the outer diameter of the acsr conductor full form is uneven.
The troubleshooting method is to check the mechanical and electrical system and eliminate the fault. Properly adjust the size of the core, control the outer diameter of the suburbs and counties to be as uniform as possible, and the stranded wire that exceeds the process regulations can be used.
Scratches on the surface
(1) The cable touches the upper or lower wall or foreign matter in the vulcanizing tube. Therefore, it is required to adjust the degree of suspension, try to make the wire core move in the middle of the cross-linked tube, and find foreign matter, and clean it in time.
(2) There is burnt 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 it is found to be burnt, it should be stopped immediately to remove it, or it will not get better by itself.
Most of the impurities in insulating materials and semi-insulating materials are brought in during mixing and during the feeding process of the extruder. Strict attention should be paid to the cleanliness of materials during operation to prevent the mixing of external impurities. Another kind of impurity is scorching lumps, its existence affects the performance and service life of the abc cable, so the temperature is strictly controlled during mixing and extrusion to prevent the occurrence of scorching.
There may be two reasons for bubbles generated in insulation, one is caused during extrusion. The solution is to select appropriate molds. There are bubbles in the shielding layer. The main reason is that there is moisture in the material. It should be dried before extrusion. The second is insufficient cooling. At this time, the following will appear. A circle of bubbles will appear on the circumference equidistant from the core.
The elimination method is to strengthen the cooling, raise the water level and lower the temperature of the cooling water.
Unqualified cable performance
(1) Unqualified free discharge and dielectric loss
The causes of dissociation discharge and dielectric loss unqualified are very complicated, and they are shielded from the outside. Whether the insulation contains bubbles and impurities is closely related to the performance of the raw materials. The elimination method is to keep the raw materials clean and strictly follow the production process.
(2) Cable insulation breakdown
The main cause of cable insulation breakdown is the mixing of insulating materials and external damage. Due to strict avoidance of external damage, the mixing of impurities should be avoided as much as possible. The semi-finished products are strictly managed to prevent stumbling.
(3) Cushion breakdown
The main reason for the cushion layer breakdown is the steel with burrs, curling, and puncture the cushion. The method of elimination is the use of different quality requirements of the steel belt. The cushion shall be made of plastic tape with a higher hardness, and it shall be ensured The thickness of the cushion.