subject: Of Cable Laying In Provisions To Protect The Tube - Cable Laying, Protection Tube - Electrical [print this page] Cable protection tube must be smooth wall, no burr. Protection tube selection, should be required to meet the conditions of use of mechanical strength and durability, and meet the following basic requirements:
(1) required intubation to suppress interference control of electrical cable, steel pipe should be used.
(2) AC single-phase cable with a single through the tube may not separate the magnetic circuit of the steel used.
1. Of some or all exposed in the air in the cable protection tube selection, shall observe the following requirements:
(1) fire or mechanical demanding place, it is appropriate steel pipe. And should be taken such as paint or zinc coated for corrosion protection requirements of environmental durability.
(2) self-extinguishing requirements to meet project conditions, the available flame retardant plastic tube. Buried in the middle part of the need for impact resistance of concrete to use site, plastic tubes should have the appropriate pressure ability, and flexible plastic pipe is preferred.
2. To the protection of buried pipe, shall meet the requirements and the depth of the compressive resistance under corrosive environment. By differential settlement of the backfill soil and other places by the larger force, it is appropriate steel.
Greater number of the same cable channel when it is appropriate pipes.
3. Protection tube diameter and the number of options through the cable, shall meet the following requirements:
(1) should wear only one per tube cable. In addition to power plants, High pressure Importance of the substation and other places outside of a motor circuit or the same equipment for all Low Motor All circuits can be combined in each tube to wear more than three Power cable Or the root control cable.
(2) tube diameter, not less than the cable diameter cables or 1.5 times the diameter envelope. Row of pores diameter pipe, but also not less than 75mm.
4. Single protection tube used, shall meet the following requirements:
(1) Each pipe not more than four elbow; not more than 3 right angle bends.
(2) to the pipe, the depth from the ground not less than 0.5m; from the intersection with the railway embankment, not less than 1m; from the ditch bottom should not be less than 0.5m.
(3) tied for possession should have not less than 20mm between the gap.
5. Use row tube should meet the following requirements:
(1) the number of pores should be reserved by the development of appropriate alternative.
(2) cable core temperature difference between the large cable, should the distance between each configuration in the appropriate row of pipes of different groups.
(3) the thickness of pipe at the top of the soil cover not less than 0.5m.
(4) pipeline should be placed in layers and compacted by leveling have enough to keep the pads on a continuous flat; vertical drainage slope of not less than 0.2%.
(5) pipe bending of the longitudinal joints shall comply with traction cable will not damage requirements.
(6) pores port deal should prevent cable damage.
6. A longer cable tube in the following parts, there should be working well:
(1) Cable pulling tension limit of the space office. The maximum spacing, according to Appendix F of this standard to determine.
(2) cable branch joints. (3) pipe or cable to change the direction of higher transferred from the row of pipes buried Department.
(4) pipeline and the need to prevent cable steep decline in the need to strengthen the fixed office.
