Why are manhole covers round?

1. The hole under the cover is round because a cylindrical shape is best able to withstand the pressure of the surrounding land. Also, a sewer access hole means leaving enough room for a person to pass through, and the cross-section of a person climbing down a ladder is basically round. So a circle is a natural shape for a sewer access hole. A round manhole cover is just there to cover a round hole.?

2, about the well cover round problem, dating back to the 13th century in France, France, when the construction of Paris, taking into account the problem of building sewers, it was proposed to rebuild the cellar as a sewer, because the French people brewing at that time is every family, almost every family has a brewing cellar,

3, due to the ground there is a round hole in the ground for the transportation of cellar winemaking barrels, in order to avoid danger, these holes in the ground to use round iron. Until the Roman Empire used the French sewerage technology for the construction of the city of Rome, the major cities around the world have chosen the Roman sewerage technology.

Expanded Information:

It plays an important role in protecting the pavement of urban roads.

It can be said that the sewer manhole cover is the only connection between the underground and the ground medium, but also on the ground water discharge of the main discharge port, it is more often play is to avoid the roadway and vehicles and pedestrians fall phenomenon.

So the manhole cover has a strong hardness and strength, and even withstand the weight of several tons of heavy dump trucks, more secure and efficient to ensure that people and vehicles travel safety.

Generally speaking, the manhole cover is usually selected from high-quality steel and in the production process after a special processing technology to deal with, so that it has a higher strength and good compression resistance in the future application.

Even when faced with strong impact and greater weight will not easily fracture and breakage of the phenomenon, to a certain extent, to avoid the occurrence of some accidents and the impact caused by; in terms of structural design, the whole after the basic cast iron manhole cover process, so that it has a light weight and easy to use features, easy to install, transportation and repair and maintenance work.

In addition to the general well cover, the market sells new ductile well cover and cast iron well cover, etc., different kinds of products to meet the different needs of customers.

Baidu Encyclopedia - Sewerage