Principle of manhole cover explosion

Not all manhole covers will explode. The manhole covers that may explode in cities include sewer manhole covers and gas valve manhole covers. In some enterprises, there are too many manhole covers that may explode, such as hydrogen valve manhole covers and some flammable and explosive gas valve manhole covers. I will not list them one by one. Now we will mainly introduce the principle of explosion in urban valve manhole covers. Sewer wells are mainly used to collect domestic sewage. Some people call them septic tanks. The composition of domestic wastewater in the well is very complex and must be cleaned and transported in time with a sewage suction truck. But sometimes, because the sewage suction trucks do not pump it out in time, a large amount of methane is produced in the sewer wells (septic tanks) in hot weather. The concentration is too high, and it will cause an explosion when exposed to open flames or sparks. When a gas valve well explodes, it is usually caused by a leak in the valve in the valve well or a gas pipeline, or an explosion caused by an open flame or spark. Everyone knows that open flames generally produce sparks. The sound of loose wire connections is all caused by sparks. Sparks are caused by mobile phone calls or incoming calls. Therefore, it is recommended that manhole covers in cities that may explode should be equipped with safety warning signs, which can reduce the occurrence of manhole cover explosion accidents.