沈海防爆
溫度分類是評估易燃氣體和防爆電氣設備燃點能力的重要安全指標.易燃氣體根據其燃燒溫度分為六個等級，而電氣設備則根據其最高表面溫度分為六個等級，分別表示為 T1、T2、T3、T4、T5 和 T6。但是，電氣設備和易燃氣體的分類標準明顯不同。
| 溫度組 | 可燃氣體的燃點溫度/℃ | 設備高表面溫度 T/℃ |
|---|---|---|
| T1 | t≥450 | 450≥t＞300 |
| T2 | 450＞t≥300 | 300≥t＞200 |
| T3 | 300＞t≥200 | 200≥t＞135 |
| T4 | 200＞t≥135 | 135≥t＞100 |
| T5 | 135＞t≥100 | 100≥t＞85 |
| T6 | 100＞t≥85 | 85≥t |
The principle behind electrical equipment’s temperature classification is that the highest surface temperature generated by the equipment should not ignite surrounding flammable gases. In other words, the equipment’s maximum surface temperature must not exceed the ignition temperature of the flammable gases.
必須注意的是 the maximum surface temperature of explosion-proof electrical equipment refers to the highest temperature that can be reached on its surface or parts under normal working conditions and under the most adverse conditions approved. This temperature should be capable of igniting the surrounding explosive gas-air mixture.
Due to varying explosion-proof designs, the maximum surface temperature could refer to different parts of the equipment. It might be the temperature on the outer surface of the enclosure, as in the case of flameproof electrical equipment, or it could be the temperature on the external surface of the equipment casing or certain internal components, such as in increased safety or pressurized electrical equipment.