Advantages and disadvantages of light burned magnesium powder

The light-burned magnesium powder itself does not burn at all, it can run continuously for a long time at 250 °C, and it can maintain normal operation for 30 minutes under the extreme state of 1000 °C, and it will not cause a fire source. Even in the case of flame grilling, as long as the flame temperature is lower than the melting point of copper, the cable can continue to be used without replacement after the flame is eliminated. No toxic fumes and gases are produced under the condition of being grilled by flames. Light Burnt Magnesium Powder

2. Strong overload protection ability

When the line is overloaded, as long as the heat does not reach the melting point of copper, the cable will not be damaged. Even if there is an instant breakdown, the crystal at the breakdown will not form carbides. After the overload is eliminated, the cable performance will not change, and it can continue to be used normally.

3. High working temperature

Since the melting point temperature of the insulating layer crystal is much higher than the melting point temperature of copper, the high temperature of the long-term normal operation of the cable can reach 250 °C, and it can continue to operate normally at a temperature close to the melting point of copper at 1083 °C in the short term.

4. Good anti-corrosion and explosion-proof performance

Because the seamless copper tube is used as the sheath, the light-burned magnesium powder has the properties of waterproof, moisture, oil and some chemical substances. The copper tube has considerable mechanical strength and therefore has good explosion-proof performance.

5. Long service life

Magnesium oxide cables are all composed of inorganic materials, so there is no insulation aging, and the service life can reach more than three times that of ordinary cables.

6. Greater flexibility in laying

Magnesium oxide cables can be laid on the bridge with ordinary cables, and can also be laid openly with special brackets, which is more flexible than ordinary cable laying, saves the investment of cable trays, and can reduce the overall cost of the project.

2. Disadvantages of Light Burned Magnesium Powder

Everything has two sides, and light-burned magnesium balls are no exception. While they have many advantages, there are also some disadvantages, which should be paid attention to in selection and construction.

1. High investment cost

Because the outer sheath of the magnesium oxide cable is composed of seamless copper tubes, the overall copper content is much more than that of ordinary cables. At the same time, the construction process of magnesium oxide cables has higher equipment requirements than ordinary cables, resulting in the price of magnesium oxide cables compared with ordinary cables. About 30% higher.

2. The joint is susceptible to moisture

The insulating layer is composed of minerals, which are easily chemically reacted with moisture in the air to generate magnesium hydroxide that can conduct electricity. In the construction of the cable head, when the bare conductor is stripped at the cable end, the insulation resistance of the cable is generally above 10MΩ, but if the cable head is not completed within 1 hour, the insulation resistance can drop to below 10MΩ, or even drop to 0.5 In the case of MΩ or less, if the outer layer is not scratched carefully, and the sealing and moisture-proof treatment is not carried out in time, the insulation value will drop quickly and gradually drop to 0, which will make the cable unusable.

3. Construction is difficult

The hardness of light-burned magnesium powder is higher than that of ordinary cables, and its weight is about twice that of ordinary cables. It is not easy to achieve a parallel and neat appearance when laying, and the lines are long and there are many joints. It is difficult to find fault points, so the construction is more difficult. It is difficult to bend into and out of the distribution box and in the bridge frame.

4. Large amount of construction work

Light-burned magnesium powder with a size exceeding 35mm is a single-core cable, such as a 70mm cable, an ordinary cable only needs five conductors of 3 × 70 + 2 × 35 in the same outer sheath, and magnesium oxide needs to reach The same specification must be assembled by 3 single-core cables of 70mm and 1 of 35mm. The delivery length of the single-core cable is short, for example, the delivery length of the 240mm cable is 69 meters. If the laying distance is longer, the production of a large number of intermediate joints will increase, which will double the construction workload.