The tank farm is an essential facility in the oil field. It is intended for receiving and storing oil. Such facilities are classified as Category II in terms of lightning protection according to RD and may be protected by standalone lightning arresters or those installed on the tanks.
Recently, ZANDZ Technical Centre has received a task to calculate the lightning protection system for the tank farm in Chelyabinsk Region. Let us consider the solution we provided below.
Example calculation of the lightning protection system for the tank farm in Chelyabinsk Region
Facility: A tank farm in Chelyabinsk Region.
Figure 1. Facility plan.
Task: To perform calculations of the lightning protection system for the tank farm in Chelyabinsk Region
Protection of buildings against lightning strikes is provided by using standalone lightning arresters.
Solutions to meet the requirements to the lightning protection system for the tank farm in Chelyabinsk Region:
1. The lightning protection is made in accordance with the Electrical Installations Code (EIC), Rev. 7, SO 153-34.21.122-2003 Instructions for Arranging Lightning Protection of Buildings, Structures and Industrial infrastructure (hereinafter referred to as SO) and RD 34.21.122-87 Instructions for Arranging Lightning Protection for Buildings and Structures (hereinafter referred to as RD), approved by Order No. 777 of Rostekhnadzor of December 26, 2012.
2. According to Table 1 of RD, the tank farm is classified as Category II of the lightning protection. It means that the farms can be protected by both standalone lightning arresters and lightning arresters installed on the facility.
3. Protection zone B of RD is taken as estimated.
4. A set of arrangements ensuring compliance with the lightning protection requirements is based on the following solutions:
- 4 x 20 m standalone lightning arresters are installed;
- 5 x 16 m standalone lightning arresters are installed;
- 1 x 14 m standalone lightning arrester is installed;
- 1 x 12 m standalone lightning arrester is installed;
- 3 x 10 m standalone lightning arresters are installed;
- lightning arresters protect tanks and explosive zones as cylinders H = 2.5 m, R = 5 m over breathing valves according to item 2.6 of RD;
- protection radius and heights at which protection zones are generated are shown in the layout in a separate file.
5. For each lighting arrester, a grounding arrangement is installed as follows:
- a horizontal grounding electrode for current flowing in two directions at 90 degrees between them. The grounding electrode is made of a corrosion-resistant steel copper-plated strip with a cross section of 4 x 30 mm, the laying depth is 0.5 m;
- in each direction at the distance of 5 m from the lightning arrester, one 3 m vertical electrode is installed; an embedded part of the lightning arrester foundation is used as a third vertical electrode;
- interconnection of horizontal electrodes, with vertical electrodes and lightning arresters is made using clamps ZZ-005-064.
Figure 2 shows hardware layout.
Table 1 includes the list of required hardware and materials.
Figure 2. Hardware layout for the lightning protection for the tank farm in Chelyabinsk Region.
Table 1. List of material requirements.
Do you have any questions about lightning protection for the tank farm or other facilities? Please, contact the ZANDZ Technical Center!
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