How to Prevent Explosions in Marine Electrical Equipment?
Explosive hazards are ubiquitous and often accompany fires and other disasters, exacerbating damage to our lives and property. Therefore, explosion prevention is essential.
So how can we minimize the risk of explosions?
First, we need to understand the basic concept of an explosion and how it occurs. We often use the explosion triangle to describe the concept of an explosion.
1. Explosion-proof Electrical Equipment
Electrical equipment is placed in an explosion-proof enclosure. This enclosure can withstand the explosion pressure of the internal explosive gases without damage or permanent deformation, and internal combustion cannot escape through its joints or structural openings to ignite external flammable materials.
2. Increased Safety Electrical Equipment
Additional measures are taken for ordinary industrial electrical equipment that does not produce sparks or arcs under normal operating conditions to improve its safety and prevent the possibility of overheating or the generation of sparks and arcs.
3. Intrinsically Safe Electrical Equipment
Under specified test conditions, if the arc or thermal effect produced by a circuit or part of a circuit, whether in normal (e.g., open or closed) or accidental (e.g., short circuit or grounding) conditions, cannot ignite a specified flammable gas or oil vapor, then that circuit or part of the circuit is considered intrinsically safe.
4. Positive Pressure Electrical Equipment
Electrical equipment is placed in a positive pressure enclosure filled with a protective gas (air or inert gas) at a pressure higher than the ambient pressure. This prevents flammable gases from entering the enclosure, thus avoiding the risk of explosion.
5. Encapsulated Electrical Equipment
Parts that could generate an arc, spark, or high temperature that could ignite an explosive mixture are encapsulated, preventing them from igniting the surrounding explosive gas mixture.
6. Oil-filled Electrical Equipment
Under normal operating conditions, all components capable of generating an electric arc are completely immersed in sufficiently deep oil to prevent ignition of explosive gas mixtures above the oil surface. Those live parts that do not generate an electric arc under normal conditions are either immersed in oil or have other approved explosion-proof features.
7. Sand-filled Electrical Equipment
All live parts are completely encased in a powdery substance. When used under the conditions specified in the design, the electric arc generated inside the enclosure cannot be propagated by flame or ignite external flammable mixtures due to overheating of the enclosure wall.
Besides these common explosion-proof types, there are also non-ignition-resistant electrical equipment and other special types of electrical equipment designed according to the site environment. Those interested can search for relevant information. Although various explosion-proof safety devices protect our lives and property at all times, it is still important to remind everyone to raise awareness of fire and explosion prevention, learn relevant knowledge, master basic escape skills, and try to avoid injury from fire or explosion.
