manhole

Manhole A manhole is actually a type of connection, a manhole is a chamber that is used to connect the network (connecting several pipelines to each other) and ways to transfer sewage and inspect, perform maintenance or adjust valves or other services (including water, sewage, telephone, electricity, storm drainage, district heating and gas) are used. In other words, manholes, especially sewer manholes, are used to connect underground lines and facilities and to connect several networks and lines to each other. A manhole is one of the most important parts of a sewer system because it eliminates the need for digging. In the urban and domestic sewage system, to connect several sewage pipelines to one route, sewer manholes are placed at regular intervals throughout the sewer system to provide convenient access at any point. Access to sewer manholes must be with safety equipment. It is necessary to prevent accidents caused by falling and harmful gases such as methane and hydrogen sulfide. Sewage manholes are used in the urban sewage system and industrial sewage, as well as with various applications in the oil, gas, petrochemical, power plants and urban transmission lines. . Sewage manholes must have at least the following standards 1. At the same time, they should be light and have high mechanical resistance in accordance with national standards. 2. The sewer manhole should have a polished inner layer with a light color. 3. The material of the sewage manhole must have high resistance against acids and bases. 4. It should have a smooth and regular surface, prevent the adhesion of environmental pollutants on the outer wall of the manhole, and have the property of being non-precipitating. 5. Its design should be such that it prevents the entry of sewage into the underground water. 6. The sewer inspection valve must have high impact capability and be resistant to earthquakes and not fragile.