1. Lightning rod

The editor of graphite grounding reminds you that lightning rods generally use round steel with a diameter of 12-16mm. If lightning strips are used, round steel with a diameter of 8mm or flat steel with a thickness of 4mm should be used. The height of the lightning rod above the protected object should be greater than or equal to the horizontal distance from the lightning rod to the protected object, and the higher the lightning rod, the larger the protection range.

2. Grounding body

The grounding body should be made of hot-dip galvanized steel, with specifications generally including a steel pipe with a diameter of 50mm and a wall thickness of not less than 3.5mm; a 50mm x 50mm x 5mm angle steel or a 40mm x 4mm flat steel, with a length generally ranging from 1.5 to 2.5m. The burial depth of the grounding body should be at least 0.7m above the ground at the upper end, and the welded parts should be re treated with anti-corrosion and rust prevention measures.

The editor of graphite grounding learned that in order to improve the grounding effect, a dedicated non-metallic graphite grounding module can also be used. This module is a grounding body mainly made of non-metallic materials, which is composed of non-metallic minerals and electrolytic substances with good conductivity and stability. This grounding body overcomes the problem of poor affinity of metal grounding bodies in acidic and alkaline soils and the easy occurrence of surface corrosion of metal bodies, which can cause changes in grounding resistance. When there is too much organic matter in the soil, it is easy to form the phenomenon of metal body surface being wrapped by ink, resulting in weakened conductivity and leakage ability. This type of grounding body increases its own scattering area, reduces the contact resistance between the grounding body and the soil, has strong moisture absorption and retention ability, reduces the electrical resistivity of the surrounding soil, increases the dielectric constant, reduces the interlayer contact resistance, and enhances corrosion resistance, thus achieving smaller grounding resistance and longer service life. The grounding body module has a square shape with dimensions of generally 500mm × 400mm × 60mm. The lead electrode is made of 90mm × 40mm × 4mm galvanized flat steel with a weight of about 20kg. The grounding body can be buried in 1-5 pieces according to the geological soil conditions and grounding resistance.

3. Down line

Round or flat steel is generally used for down conductors, and round steel with a diameter of not less than 8mm should be preferred. If flat steel is used, the cross-sectional area should not be less than 4mm2; For higher requirements, double-layer insulated multi strand copper wire with a cross-sectional area of 35mm2 should be used.

4. Special drag reducing agent

The editor of graphite grounding reminds you that the grounding system specific drag reducer belongs to the category of physical long-term anti-corrosion and environmentally friendly drag reducer. It is a resin based co organism composed of polymer water absorbing materials, electronic conductive materials, and carbon based composite materials. It has the advantages of non-toxic, odorless, corrosion-resistant, and pollution-free, and meets the requirements of national high-quality soil environmental standards. Its conductivity is not affected by changes in acid, alkali, salt, temperature, etc. It has good moisture absorption, moisturizing, and antifreeze abilities, and will not be lost due to the presence of groundwater. It has a long-term improvement effect on soil resistivity. The use of specialized resistance reducing agents in grounding systems can save engineering costs, reduce soil resistivity, stabilize grounding resistance, and prolong the lifespan of grounding systems.

5. Calculation of the dosage of grounding module and resistance reducing agent.

The editor in charge of graphite grounding believes that based on the soil resistivity of the grounding grid soil layer, the following formula can be used to calculate the amount of grounding modules used. The grounding modules are horizontally buried, and the grounding resistance of a single module is r=0.068 ρ/? The total grounding resistance after parallel connection is rn=r/(n η).

Among them, ρ is the soil resistivity, measured in ω? M; Take a and b as the length and width of the grounding module, in meters; r as the grounding resistance of a single module, in units of ω; rn as the total grounding resistance, in units of ω; n as the number of grounding modules; η is the module adjustment coefficient, generally ranging from 0.6 to 0.9.

The editor of graphite grounding reminds you that the amount of resistance reducing agent used depends on the soil. The thickness of the laying on the grounding body should be between 5-15cm. The grounding body should be placed horizontally and used at a rate of about 6kg per 0.5m.