KSD introduces you to three common laying methods of outdoor Fiber Optic Cable, namely: Duct laying, direct buried laying and overhead laying. The following explains the laying methods and requirements of these three laying methods in detail.
1. Duct laying
Duct/pipe laying is a widely used method in optical cable laying engineering, and its laying must meet the following requirements:
1. Before laying the optical cable, the sub-holes should be inserted in the pipe hole. The sub-tube of the same color should always be put through one hole of the optical cable, and the unused sub-tube nozzle should be protected by plugging.
2. Taking into account that the laying process is manual operation, in order to reduce the loss of optical cable joints, the pipeline optical cable manufacturer should use the whole spool laying.
3. During the laying process, the traction during laying should be reduced as much as possible. The entire fiber optic cable should be laid out from the middle to the two sides, and each manhole should be arranged for auxiliary traction in the middle.
4. The position of the holes for the fiber optic cables should meet the requirements of the design drawings, and the pipe holes must be cleaned before laying the pipeline fiber optic cables. The sub-hole pipe should be exposed in the hand hole about 15cm of the extra length of the pipe hole.
5. The interface between the hand-hole inner tube and the plastic textile network tube is wrapped with PVC tape to avoid infiltration of sediment.
6. When the optical cable is installed in the human (hand) hole, if there is a pallet in the hand hole, the optical cable is fixed on the pallet. If there is no pallet in the hand hole, the optical cable should be fixed on the expansion bolts. The hook mouth is required to be downward.
7. The fiber optic cable should not be bent within 15cm of the outlet hole.
8. Plastic signs are used in each hand hole and on the optical cable and ODF rack in the computer room to show the difference.
9. Optical cable ducts and power ducts must be separated by at least 8cm thick concrete or 30cm thick compacted soil layer.
2. Directly buried laying
If there are no conditions for overhead use under the laying conditions and the laying distance is relatively long, direct buried laying is generally adopted, and direct buried laying should meet the following requirements:
1. Avoid areas with strong acid or alkali corrosion or severe chemical corrosion; when there are no corresponding protective measures, avoid termite-hazard areas and heat sources or sections that are easily damaged by external forces.
2. The optical cable should be laid in a trench, and the surrounding area of the optical cable should be covered with a layer of soft soil or sand with a thickness of not less than 100mm.
3. A protective board with a width of not less than 50mm on both sides of the optical cable shall be covered along the entire length of the optical cable, and the protective board should be made of concrete.
4. The laying position is in places with frequent excavation such as access roads in cities and towns, and eye-catching signs can be laid on the protective board.
5. At the laying position in the suburbs or in the open zone, at about 100mm along the straight line of the optical cable path, at the turn or at the joint, clear azimuth signs or stakes should be erected.
6. When laying in a non-frozen soil area, the fiber optic cable sheath to the foundation of the underground structure shall not be less than 0.3m, and the depth of the fiber optic cable sheath to the ground shall not be less than 0.7m; when it is located in a roadway or cultivated underground, it should be deepened appropriately and not less than 1m.
7. When laying in a frozen soil area, it should be buried below the frozen soil layer. When it cannot be buried deeply, it can be buried in a dry frozen soil layer or backfill with good soil drainage. Other measures to prevent damage to the optical cable can also be taken. .
8. When directly buried optical cable lines cross railways, highways or streets, protective pipes should be worn, and the protection range should exceed 0.5m above the roadbed, both sides of the street pavement and the side of the drainage ditch.
9. When the directly buried optical cable is introduced into the structure, a protective tube should be installed at the through-slope hole, and the nozzle should be blocked by water blocking.
10. The net distance between the joints of directly buried Fiber Optic Cable and the adjacent Fiber Optic Cable shall not be less than 0.25m; the joint positions of parallel Fiber Optic Cable should be staggered with each other, and the net distance shall not be less than 0.5m; the joint positions on the slope terrain should be horizontal; for important circuits It is advisable to leave a spare way to lay the optical cable in the local section starting from about 1000mm on both sides of the optical fiber cable joint.
3. Overhead laying
Overhead laying can exist between buildings, between buildings and telephone poles, and between telephone poles and telephone poles. The actual operation depends on the situation at the time. When there are telegraph poles between buildings, wire ropes can be erected between the buildings and the telegraph poles, and the Fiber Optic Cable can be tied to the wire ropes; if there are no telegraph poles between the buildings, but the distance between the two buildings is about 50m, Fiber Optic Cable can also be erected directly between buildings through steel cables. The laying requirements are as follows:
1. When laying Fiber Optic Cable in a flat environment by overhead, use hooks for hanging; laying Fiber Optic Cable on mountain or steep slopes, and use lashing methods to lay Fiber Optic Cable. The optical cable connector should be located on a straight pole that is easy to maintain, and the reserved optical cable should be fixed on the pole with a reserved bracket.
2. The optical cable of the overhead pole road is required to make a U-shaped telescopic bend every 3 to 5 bars, and 15m is reserved for every 1km.
3. The overhead (wall) optical cable is protected by galvanized steel pipe, and the pipe mouth should be blocked with fireproof mud.
4. Overhead Fiber Optic Cable shall be hung with optical cable warning signs every 4 bars or so and in special sections such as roads, rivers and bridges.
5. A three-pronged protective tube should be added at the intersection of the empty suspension wire and the power line, and the extension of each end shall not be less than 1m.
6. The cable for poles close to the highway should be covered with glow sticks with a length of 2m.
7. In order to prevent the suspension wire from injuring people due to the induced current, each pole pull wire must be electrically connected to the suspension wire. Each pull wire position should be installed with a pull wire ground wire. The suspension wire is required to be directly connected with a bushing ring and grounded directly at the terminal.
8. The overhead optical cable is usually 3m away from the ground. When entering the building, the U-shaped steel protective sleeve on the outer wall of the building must be worn, and then extend downward or upward. The aperture of the optical cable entrance is generally 5cm.
Post time: Jul-25-2020