Every day, when we move the city, in our field of view and then hit a manhole cover.This object of the urban landscape since childhood has become so familiar and, I would even say prosaic that, as a rule, we do not pay attention to it.
And in vain ... Do you ever wonder why manholes round?Not square, not rectangular, not oval, and round it?
I'm afraid that if earlier the issue and no interest, now you definitely want to get the answer.
Section 1 Hatches sewer: plastic, cast iron, rubber, plastic.What role do they perform?
First of all, it should be noted, they are an important part of any manhole and install them directly into the body.Moreover, the subject should be placed so that it is snug enough, and does not obstruct any at running it, or when carrying out certain types of communication works.
If you look closely, you will notice that each cover has an opening that is designed to measure the level could well gassed.
cover heavy, weighing 50 kg.And this massive is not accidental, it is created deliberately to exclude any likelihood of its bias.It must remain stationary even at very strong ground motion road transport.
Today in the CIS countries there is not only a massive theft of covers, but also their active collection point of scrap metal.That is why it was decided to cover hatches with special concrete slabs.However, this method brings many disadvantages.Firstly, the coating breaks down fairly quickly, and secondly, when hit by a car, it just turns into a potential danger, causing a massive traffic accident.
Section 2. We try to answer the question.
As it turned out, speculation on this matter mass, and in this article I will focus on three versions.
- Why manholes round?Explanation first.Logical.
What would happen if such a cap had, say, a square shape?Well, strictly speaking, nothing bad would happen.Although to be honest, I'm sure it would cause some inconvenience.Above all, from purely geometric considerations.We cover a square diagonal size exceeds the length of the side, and therefore it may fall inside.With round, even hypothetically, that does not happen.It turns out that the latter is much safer becauseit will not fall in, and, therefore, in the event of an extraordinary situation inside the collector will not be affected workers, and the car will remain intact, not suddenly drove into a hole formed on the pavement.
- Why manholes round?Explanation of the second.That's funny.
once heard how tired, apparently, from the thousands of "why?" The young mother, tried to answer the question like a baby.She said something like, "Well, the opening round, he can see how else they can cover?" I smiled and thought.But it is right in principle, but, why, then, do not make square holes or is it just a coincidence?He asked his friend, the architect.It turns out that all sewage is much easier to dig a well, besides, he is a more technologically advanced, lasts longer and does not so much exposed to the transformation and changes in temperature.Well, then, in this interpretation, too, there is some truth.
- Why are manholes round.Explanation of the third.Interesting.
workers believe that this type of cover is easier to transport.Well, imagine that you need to move it from one place to another.Was she a square, it would have to bear themselves could not have done so would have involved no less than 2 people, and not weak men asThis object, as mentioned above, has a decent weight.But a round, if necessary, you can easily roll.In addition, the best round cover lies on a specially designed place because it does not need to twist, combining the necessary holes.And if you think about the range of safe transport easier than a square or a triangle, and arms and legs are intact, and the edge of the door does not repulse.
