Clicks1. Sampling: All sampling workers must be clean to prevent misjudgment. Sampling at the 50mm section of the cable end:
A) A section of the core wire is 100mm long;
B) Take the core wire insulation tape length 100mm;
C) Take the lead-covered paper insulation tape with a length of 100mm;
2. Inspection method: insert the samples into 150C cable oil (or 130C transformer oil) in turn. If there is a hissing, beeping sound or foam, indicating that it is damp, you can cut a 100mm long cable and try again. Until there is no sound and no foam (or burn with fire, if there is noise or foam, it means that it is damp, otherwise it is considered that there is no damp.);
3. Cut off the damp end, measure the insulation resistance and withstand voltage test, and start to make the cable head after passing the test;
Three, adjust the cable accessories:
First place the cable that needs to be the cable head, place it in the position, and measure the actual measurement. Generally, a certain margin should be reserved (leave a head margin), and the bending radius meets the bending radius required by the cable, leaving enough for head volume ( The length of the core wire is according to actual requirements), and the excess part is cut off;
Four, cut cable accessories:
1. The cut size is as follows:
2. Cutting process:
a. Cut the size according to the above figure, and the position according to the design and actual measurement. The section (edge) should be neat and free of flanges and burrs;
b. Do not damage the insulation or shielding layer of the adjacent lower layer during cutting. Use a detergent to remove fine debris and oil stains on the profile;
c. Partial cutting process: The cut size is as shown in the figure above, and the position is according to the design and actual measurement. The section (edge) should be neat and free of flanges and burrs;
d. Do not damage the adjacent lower insulation or shielding layer during cutting. Use a detergent to remove fine chips and oil stains on the section, and cut burrs;
e. When stripping the lead sleeve, first cut a deep mark of 2/3 of the lead thickness in the incision, and then make two axial lines on the stripping side until the cable end is 7-8mm wide, parallel, and deep as the lead thickness 2/ 3 For deep marks, use a screwdriver to pick up the lead strip from the end, roll (pull) the lead strip along the mark, and then peel off the lead pipe, repair the burrs of the lead mouth to make it smooth;
f. For the vulnerable surfaces that have been cut and decontaminated, such as the main insulation, shielding tape, and alcohol wrapping tape to protect them from pollution and moisture;
g. When taking the heat-shrinkable tube in the section, the cut should be round, smooth, free of burrs, convex and concave edges and cracks, otherwise it is easy to tear when shrinking.
3. Keep the shielding layer 25mm from the lead port, and cut off the rest together with the filler. When cutting, the blade should not damage the core insulation outside the cable, and sweat should be removed with an alcohol cloth. In order to keep the shielding layer cut smooth and tidy, a knife can be used to press the cut. Tear it off and repair it again;
4. After verifying the correct phase sequence of the core wire, bend the core wire according to the actual wiring situation and measure the length of the core wire. The shortest one-phase insulation retention shall not be less than 350mm, and the rest shall be cut off;
5. Crimping terminal:
At the core wire end, measure the terminal connection depth and add a distance of 5mm, and cut off this section of insulation. If the cross-section of the core wire is fan-shaped, use the jaws to make the core into a circle, remove debris and oil, put on the terminal, make the connecting tube sleeve to the predetermined mark, and straighten the direction of the terminal deflector when pulling the wire. The splicing tongs correspondingly press 2-3/indentation. When crimping, stop for one minute after the mold is aligned to fully deform the splice and core pressure port, and then unload the mold;
6. Fixed oil resistant pipe:
Roughen the terminal tube to remove oil scraps, fill in the main insulation and terminal crimping pit with pressure-resistant oil glue to flush out the air, and add a layer of oil-resistant glue (2-3mm) to the terminal tube. Use glue after removing the protective tape Press the main insulation 10mm, put oil-resistant (white) on the core insulation, the distance between the lower mouth of the pipe and the lead package is 50mm, and the upper pressure of the upper mouth to the terminal connection mouth is 10mm, shrink from the bottom up, the heat shrink temperature is controlled between 110-140C, if used Pay attention to keeping the flame distance of the gasoline blowtorch, not too close. When the preheating starts, the flame will slowly approach and move the flame around to ensure uniform shrinkage, damp removal and air purging.
When the heat-shrinkable material begins to shrink, the flame moves down slightly, that is, the material that will shrink in the next step is preheated, and the shrinkage is slow until the entire tube is completely shrunk. When the tube is fully shrunk, you need to bake it-again. Make the shrinking force uniform, the surface is smooth, there is no wrinkle and the inner outline can be seen, a small amount of glue is extruded in the seal, and the alcohol cloth is used to clean the dust.
7. Fixed stress tube, one stress tube for each phase, the lower port is 80mm from the lead port, and it is fixed by shrinking from bottom to top. The process is the same as that in 5.6;
8. Make a three-pronged "apple" type:
Take the oil-resistant glue and knead it into a cone, and press it into the three prongs. 70-80mm roughing down from the lead port, remove the dirt and see the metallic luster, lead the port slightly preheated, the self-stressing tube 20mm below the lower port of the first phase separation, and then package "apple shape", wrap to the lead port 10mm down.
It looks like an "apple" and its outer diameter is 15mm larger than the cable outer diameter. After wrapping, the conductive glue at the lead opening is 40mm wide, and the lead opening is 20mm above and below, and then the "apple" is slightly heated to adjust the shape.
9, fixed three-pronged gloves:
First preheat the lead bag, and press down the glove as much as possible to meet the 10mm lead bag volume in the cover. First preheat, shrink the "apple" type, shrink the lead bag section, and then shrink the glove branch;
10. Fixed insulation pipe:
When split-phase casing, the mouth end of the rubber-coated tube should be pushed down to the outside of the finger, and the package should be shrunk from bottom to top. The position of the preheating terminal is shown as the transitional sheath shown in the figure below. The phase color should be consistent with the phase sequence, and the process imitates item 5.5.2;
11. Ground wire:
The location is shown in the figure below. First remove the rust from the steel strip and the lead-clad soldering area to see metallic luster, and then tie the ground wire to the lead-clad and steel strip with copper wire. Apply solder paste to the solder joints, use a blowtorch to preheat and bake the solder dripping onto the solder joints, then use a blowtorch to heat the solder to melt it without dripping, and then press and polish it with a hard cloth to form a flat solder joint. After it cools, wrap three to four layers of plastic protective layer on the exposed lead steel strip;
12. Installation of rainproof skirt for outdoor terminal head:
The size of the outdoor terminal is larger than that of the indoor terminal. The method is the same as that of the indoor terminal. There is only one more process to install rain-proof skirts one by one, see 5.12 process flow. The method of adding the skirt is: separate the core wire and set the three-hole skirt with wind to fall into its installation position, use a blowtorch to heat the skirt installation hole to shrink the core wire and remove dirt. From the top of the three-hole skirt, install two single-hole skirts at a distance of 100mm per phase. But the layout should be even and should not touch each other, for this reason, it can also be installed slightly staggered. Decontamination with alcohol cloth, after cooling, the pressure is qualified, then it can be put into operation.
13. Installation of DC 75KV single-core cable head:
The cut size is shown in Figure 1.2, and the internal structure is shown in Figure 3.4. The method is the same as the 10KV cable head.
If the indoor cable head has an accessory porcelain sleeve, the rain skirt can be omitted.
The indoor heat shrinkable terminal layout of the DC 75KV95mm2 dust collector cable is attached as attached picture 1.
