Can cable trays be used in oil tank farms?
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Cables in oil tank areas are generally buried underground. Yesterday, the design institute said that cable trays can be installed in the oil tank area, but they didn't tell them the specific specifications. It just means that cable trays and process ducts cannot be on the same layer. Does anyone know the regulations in this regard? Please help provide a specification number. Also, can the power cable tray and instrument cable tray be placed on the same floor?
You probably can't leave. Check the petroleum construction regulations.
It can be walked, but the rule is that there can be no joints. . It’s not that electrical equipment cannot be on the same level as pipelines, there are distance requirements. . The layer of the bridge is related to the density of the medium in the process pipeline. The density of the medium is greater than that of the air in the previous layer, and the density of the medium is smaller than that of the air in the lower layer (this point should be next to it). This is all to prevent leakage from affecting the bridge instrumentation and electrical can go to the first layer. . Because electricity is not afraid of interference. . If you are afraid of the instrument, stay away from it
- -To supplement the above, if there are many cables in the tank area, it is better to bury them directly if there are fewer bridges. .
It should be a combination of bridges and buried pipes. It is better to use bridges for the main lines. The cables going to each tank should be buried in pipes and passed through cables.
Instruments and electrical equipment must not go on the same bridge. Instrument signals are generally 4-20MA current signals. If they go on the same bridge, it is easy to receive interference and cause measurement deviations.
Code for design of cables of electric engineering GB 50217-20077. 0. 10 Mineral insulated cables can be used when fire resistance requirements are high in oil tank areas, important wooden public buildings, high temperature places and other places where the laying and installation are economical and reasonable. The cable tray cannot hinder normal process production and maintenance. Power cables and instrument cables run together, which will interfere with weak points. Normally, they are not on the first floor. Special baffles and the like may also be on the first floor.
When electrical instruments must be on one floor, our usual approach is to set up two parallel ones.
Long experience......................
I agree with those on the 7th floor, you can walk in the tank area, but the instruments and electrical cables must be spaced apart!
Thank you all for your answers. Is there a standard for the spacing distance between power cable trays and instrument cable trays placed on the same floor? Just keep it as far away as possible. The instrument bridge is a fully enclosed metal trough.
I saw it a few days ago, but I only found this specification GB50217-2007 5. 1. 8. In addition to complying with the provisions of Articles 3.6.6 to 3.6.9 of this specification, the weak current loop control and signal cables that suppress the intensity of electrical interference should take the following measures when necessary.: 1 When laying parallel to power cables, the distance between them should be as far away as possible. ； For power cables with high voltage and current, the spacing should be farther. There is also a specification that only when the number of instrument cables is small, it can be parallel to the power supply. I don’t remember the specific specification. But if you still have questions, I will try my best to help you find the level you require.
Under normal circumstances, the distance between the instrument bridge and the cable bridge is generally designed to be 1 meter.
Spacing between electrical and instrumentation trays. In theory, 800 can meet all requirements. Generally set it to 1000! ~! :P
The distance between electrical and instrument bridges should be kept at 600MM (in parallel conditions), and they cannot be laid on the same layer. When laying power cables and electrical control cables, try to keep them as far apart as possible, with a distance of more than 100MM, not to mention instrument cables. Of course, if the instrument is a switch signal and is equipped with a partition, generally only the equipment manufacturer can consider laying it in the same slot box when laying supporting cables, provided that the manufacturer's technical personnel approve it.
The distance between electrical and instrument lines on the same floor pipe gallery is required to be more than 1 meter in the piping specifications of Lanzhou Petrochemical Institute. In other specifications, I remember that there is a requirement to leave gaps, but I can’t remember the details.
There are distance requirements between electrical instrument cables and bridges. If the power cables are directly buried, can the instrument cables be directly buried together?
Cable trays and pipelines on the same layer only need to meet the distance requirements. It is possible to walk on bridges in the irrigation area.
If instrument cables and power cables run on the same bridge, it is recommended to use a bridge with a partition in the middle.
Power cables and instrumentation and control cables cannot be placed in a cable tray. The startup of high-power electrical equipment will produce strong current electromagnetic interference.
What does a fully enclosed metal tank look like?