Pebbles under electrical equipment

The pebbles in the oil pool are mainly used for fire protection. Article 5.4.5 of the national standard 50060-92 stipulates that a pebble layer of no less than 250mm thick should be laid in the oil storage pool, with a pebble diameter of 50-81mm. When an accident occurs, such as oil injection or explosion, the oil from the transformer will be unloaded into the oil unloading pit and then flow to the accident oil pool. It prevents the oil from still burning when it leaks to the ground when the transformer catches fire, and it also does not block the oil (water) hole at the bottom of the oil drain pit. Some pools have grilles, and some do not. Those who make the grille put the pebbles on top of the grille. ； If no grilles are used, pebbles are placed in the oil unloading pit.

I think my main role is isolation. Under normal circumstances, rainwater and transformer oil in accident situations will flow into the accident oil pool through the gaps between the pebbles, while longer solid impurities are filtered to avoid clogging the accident oil pipe.

Pebbles under electrical equipment? Is it the pebbles under the transformer? Norms: There should be an oil storage tank at the bottom of a large oil-immersed transformer. The area should be slightly larger than the plane occupied by the transformer and the depth should be about 1M. The main purpose of laying pebbles with a diameter of about 10CM is to absorb oil leakage from the transformer. Instead of absorbing the oil, it allows the oil to leak out. There is a slope below the transformer with a grille at the lowest point, and the lower oil pipe leads to the accident oil tank. The drained oil will flow to the accident oil tank! The purpose is to allow the oil to flow into the oil storage pit in the shortest time, and when the transformer fails and catches fire, the oil inside the oil storage pit is not easy to burn due to the pebbles. Even if it burns, it will not easily form a large flame due to the pebbles. The cobblestone surface is smooth and the contact area is large. When oil leakage occurs in the transformer, the oil can leak out quickly. I haven't found any requirement to lay cobblestones underneath other electrical equipment. If there are, the purpose should be similar.

It is used to prevent fires. Large power transformers are paved with cobblestones under them. This is mainly to prevent the transformer oil from burning and flowing everywhere in the event of an accident. Laying a layer of cobblestones uses its surface tension to inhibit its flow and reduce the area of ​​​​the fire. There are relevant regulations for this.

The lower part of the transformer is an accident oil reservoir. A steel mesh is added to the upper part of the oil storage tank, and pebbles are laid on the steel mesh. When a running transformer suddenly explodes and catches fire, the oil sprayed out or discharged from the accident oil drain valve flows into the oil storage pool through the pebbles. At this time, the pebbles play an isolation role, reduce the intensity of the fire, and facilitate fire extinguishing. The purpose of paving pebbles is to prevent the oil in the transformer from splashing when the transformer catches fire or explodes. ； Second, the high-temperature transformer oil can reduce the intensity of the fire after being cooled by pebbles.

Natural pebbles, no polishing required； Other standards: Is the cobblestone-covered area under the transformer foundation we usually see the transformer's oil storage pit? according to procedures: “For outdoor transformers and other oil-immersed electrical equipment with a single oil volume of more than 1,000kg, oil storage pits and oil drainage facilities should be installed ； The volume of the oil storage pit should be determined to accommodate 100% of the equipment oil volume or 20% of the equipment oil volume. When an oil storage pit is set up according to 20% of the equipment's oil volume, an oil drain pipe should be installed at the bottom of the pit to drain the accident oil into the accident oil storage pit. The inner diameter of the oil drain pipe should not be less than 100mm, and the oil should be able to be drained quickly in the event of an accident. The pipe mouth should be equipped with an iron grid filter. ” Principle of cobblestones dedicated to transformers: Cobblestones "armor" intercepts oil pollution. Under the transformer with huge oil pollution, it is neither a bare ground nor a flat cement floor, but covered with gray-blue iron grates. The working principle of cobblestones for transformers in Xiangxi Tujia and Miao Autonomous Prefecture. Reservation phone number: :. About 10 centimeters below the iron grate, there is another thick layer of pebbles (this is the transformer pebbles). These seemingly inconspicuous iron grates and pebbles are actually the concrete embodiment of the "Green Olympics" environmental protection concept. It turns out that normal oil dripping occurs when the transformer is working. Oil droplets passing through the iron grate will be intercepted by the cobblestones below and will no longer drip directly to the ground, thus preventing fires and contaminating the land. Customer requirements are the goal of our efforts, and customer needs are the purpose of our work. Everything is going on with our efforts, from the original small handicraft workshop to the beautiful workshops, factories, and office buildings now, everything is the result of our efforts. Because I believe that if you pay, you will be rewarded! About 5-8cm ； Light colored pebbles are preferred ； According to the ministerial standards, there should be an oil storage tank at the bottom of a large oil-immersed transformer. The area should be slightly larger than the plane occupied by the transformer, and the depth should be about 1M. The main purpose of laying pebbles with a diameter of about 10CM is to absorb oil leakage from the transformer. Related standards: 7.3.4 of the typical fire protection regulations for electrical equipment DL5027-1993 stipulates that it is 50-80mm. Article 5.4.5 of "Design Specification for 3-110KV High Voltage Distribution Equipment" (GB 50060-92) A pebble layer with a thickness of not less than 250mm should be laid in the oil storage tank. The diameter of the pebbles should be 50-80mm. The surface is slightly rough, which is easy to absorb oil stains and does not slip when stepping on it. ； Transformer pebble size standard: In fact, the lower part of the transformer is an oil unloading pool or oil unloading pit (or similar name), leading to the accident oil pit or accident oil pool. A steel mesh grille is added to the upper part of the oil unloading pool, and cobblestones are laid on the steel mesh grille. When a running transformer suddenly explodes and catches fire, the oil sprayed out or discharged from the accident oil drain valve flows into the oil unloading pit through the pebbles, and then flows to the accident oil pool. The cobblestones at this time play an isolation role, reduce the intensity of the fire, and facilitate fire extinguishing. ； In addition, after the high-temperature transformer oil is cooled by pebbles, the fire intensity can be reduced.