Damping method of nodular cast iron manhole cover


The biggest feature of the ductile ironmanhole cover is the prevention of wear and tear. The heavy-duty spheroidmandrel cover can be under pressure and can be pressurized at 21T. Even if theload pressure is above its limit, the ductile iron manhole cover does notrupture like the ordinary cast iron manhole cover, but is slightly deformed,giving the car and pedestrians a certain level of tranquility.