Luke's cover is cast -iron

## Luke Cast iron heavy: indestructible guardian of underground utilities
Cast iron lugs of hatches are the usual element of the city landscape. We barely notice them, stepping through them every day, but these inconspicuous details of urban infrastructure perform a very important function, ensuring the safety and uninterrupted operation of underground utilities. And the most difficult of them, especially cast -iron ones, are real long -livers who survived more than one generation and more than one reconstruction.
### History and Strength of the Material
Cast iron, as a material for the manufacture of hatches covers, has been used for decades, due to its strength and durability. A heavy cast iron cover, a few centimeters thick, can withstand huge loads: from the weight of passing cars to random blows and falls of heavy objects. It was this reliability that determined their prolonged use. Of course, other materials appear today, but heavy cast iron still remains the standard of strength and reliability for hatches covers, especially in places with intensive movement. Its history is the history of the security and stability of underground communications.
### Aesthetics and functionality
Although many perceive cast -iron hatches of hatches as simple functional elements, they also have a certain aesthetics. Their rough, but at the same time monumental texture, often decorated with knocked out patterns or marking, gives them a special charm, invisible to the majority, but tangible to an attentive observer. This is a kind of secret beauty of the urban environment, a symbol of reliability, hidden under our feet. Functionality and aesthetics here are harmoniously combined, creating something more than just a hatch cover.
### Modern analogues and prospects
Despite all the advantages of cast -iron covers, today lighter and modern materials are actively developed and used, for example, composite materials or high -strength cast iron. They have increased corrosion resistance and less weight, which simplifies their installation and maintenance. However, heavy cast iron lids still remain in demand, especially in places with high intensity of movement and large loads on the surface. Perhaps in the future their role will decrease somewhat, but the heritage of these indestructible guards of underground utilities will recall itself for a long time on city streets.