Duct cable and direct buried cable
We often talk about the concept of optical cable, but in fact, many friends don't know much about the detailed knowledge of optical cable. For example, what is a pipeline optical cable and a direct buried optical cable, or what is the difference between a pipeline optical cable and a direct buried optical cable? Let's go and find out.
What is pipeline optical cable and direct buried optical cable
Duct fiber optic cable
Duct optical cable is an optical cable used outdoors in the access network or customer premises network. A type of communication optical cable laying method. Pipe laying is generally in urban areas, and the environment for pipe laying is better, so there is no special requirement for the sheath of the optical cable, and no armoring is required. Before pipe laying, the length of the laying section and the position of the connection point must be selected.
When laying, mechanical bypass or manual traction can be used. The pulling force of one pull should not exceed the allowable tension of the optical cable. The materials for making pipes can be selected from concrete, asbestos cement, steel pipes, plastic pipes, etc. according to geography.
direct buried cable
Direct buried optical cable is a communication optical cable laying method. This kind of optical cable is armored with steel tape or steel wire on the outside, and is directly buried in the ground. It is required to have the performance of resisting external mechanical damage and the performance of preventing soil corrosion.
What is the difference between pipeline optical cable and direct buried optical cable
The following preparations should be made before laying the pipeline optical cable
1) Check the position of the pipe hole occupied by the optical cable according to the design;
2) The hole position selected on the same route should not be changed. For example, when changing or turning, it should meet the requirements of the bending radius of the optical cable;
When laying optical cables manually, each manhole should be guarded; when mechanically laying optical cables, manholes should be manned.
When the optical cable penetrates the pipe hole or the pipe turns or crosses, a guiding device or a bell mouth protection tube should be used, and the outer sheath of the optical cable should not be damaged. Apply a neutral lubricant around the cable as needed.
The length of a single traction cable is generally not more than 1000 meters. When it is too long, 8-character segmented traction or middle-assisted traction should be used.
After the optical cable is laid, it should be under the unified command of a special person, and the optical cable should be placed on the specified pallet one by one, and an appropriate margin should be left to prevent the optical cable from being too tight.
The reserved length of the optical cable in the manhole where the joint is located should meet the requirements in the table; the optical cable reserved for special design requirements is too tight.
The protection measures for pipeline optical cables shall meet the following requirements:
1) The optical cable in the manhole can be protected by a serpentine hose (or soft plastic tube) and bound on the cable tray or handled according to the measures required by the design;
2) The nozzle should be plugged;
3) Optical cables in manholes should have identification marks;
4) In severe cold areas, antifreeze measures should be taken according to the design requirements to prevent damage to the optical cable.
The laying method of plastic sub-pipes is basically the same as the laying of optical cables, and should also meet the following requirements:
1) When laying more than two sub-pipes without color markings, the ends should be marked;
2) The ambient temperature for laying the plastic sub-pipes should be between -5oC--+35oC;
3) The length of continuous laying of plastic sub-pipes should not exceed 300 meters;
4) The maximum pulling force of the tractor tube should not exceed the tensile strength of the tube, and the traction speed should be uniform;
5) The excess length of the sub-pipe in the manhole should meet the design requirements;
6) For the pipe hole of the plastic sub-pipe, a plastic pipe plug should be installed (other methods can also be used) to fix the sub-pipe;
7) The sub-pipe shall not have a joint in the middle of the pipeline;
8) After the sub-pipes are laid out, the nozzles should be temporarily blocked; the sub-pipes not used in this phase of the project must be blocked (caps) at the pipe ends.
direct buried cable
The distance between the direct buried optical cable and other buildings and underground pipelines shall meet the specified requirements.
Optical cables laid in the same groove shall not cross or overlap, and should be pulled separately and laid at the same time.
The laying of direct buried optical cables shall meet the following requirements:
1) The depth of the optical cable trench should meet the regulations, and the bottom of the trench should be flat without gravel; the bottom of the stony or semi-stony trench should be covered with 10 cm thick fine soil or sand;
2) When mechanical traction, ground pulleys should be used;
3) During manual lifting, the optical cable should not be bent less than the specified radius of curvature, and the phenomenon of mopping the ground and pulling too tightly;
4) The optical cable must be placed flat at the bottom of the trench, and must not be vacated and arched;
5. When the optical cable is laid on a slope with a slope greater than 20° and a slope length greater than 30 meters, it should be laid in an "S" shape or treated according to the design requirements;
6) During the laying process or after laying, the outer sheath of the optical cable should be checked in time, and if damaged, it should be repaired immediately; after the direct buried optical cable is laid, the insulation resistance of the optical cable sheath to the ground should be checked.
7) The optical fibers and copper wires in the optical cable must be checked and confirmed to meet the quality acceptance standards before the full trench can be returned to the soil.
The backfill soil for optical cable trenches shall meet the following requirements:
1) Backfill 15 cm thick broken soil or fine soil first, it is strictly forbidden to push stones, bricks, frozen soil, etc. into the ditch, and should be leveled manually;
2) The backfill should be 10 cm above the ground.
The above is the whole content of what is the difference between pipeline optical cable and direct buried optical cable and the difference between pipeline optical cable and direct buried optical cable. I believe that after reading this article, you have a certain understanding of pipeline optical cable and direct buried optical cable, and hope to give you help. .