At present, it is difficult to imagine the life of large and small cities, as well as industrial enterprises without an established pipeline system. They supply liquids and gases, allow people to heat homes, and enterprises to work successfully. However, taking advantage of the existence of gas pipelines, one must remember that gas communications are quite dangerous, and their damage is fraught with a serious accident.
From the history of gas pipelines
The first gas pipelines were used in ancient China. Bamboo was used as pipes, but there was no excess pressure in the pipes and gas was supplied by gravity. Compounds of bamboo pipes were packed with tow, such facilities allowed the Chinese to heat and light their homes, to evaporate salt.
The first European gas pipelines appeared in the second half of the 19th century. Then the gas was used to create street lighting. The first streetlights were oil, and in 1799, the Frenchman Lebon proposed thermal tubes that could illuminate and heat rooms. The idea was not supported by the government, and he equipped his house with thousands of gas horns, which until the death of an engineer remained a Parisian attraction. Only in 1813, the students of Lebon managed to start lighting cities in this way, but this was already in England. It came to Paris six years later, in 1819. Artificial coal gas was used as fuel.
St. Petersburg began to heat the premises by transferring gas through a gas pipeline in 1835, and Moscow in 1865.
Types of gas pipelines depending on the gas pressure inside them and the laying method
A gas pipeline is a construction of pipes, supports and auxiliary equipment designed to deliver gas to the desired location. The movement of gas is always carried out under pressure, on which the characteristics of each section depend.
Gas pipelines are trunk or distribution. The former transport gas over long distances from one gas distribution station to another. The second are designed to deliver gas from the distribution station to the place of consumption or storage. The composition of the pipeline may include either one or several lines connected by a single technological chain.
Gas pipelines come in two categories, depending on the gas pressure in them.
- The first category of gas pipelines operates under pressure up to 10 MPa.
- The second category of gas pipelines is designed to work with gas, the pressure of which is up to 2.5 MPa.
Gas distribution pipelines are divided into three groups depending on the gas pressure in them.
- Low pressure. Gas is transferred to them at 0.005 MPa.
- Medium pressure. Gas transmission in such pipelines is carried out under pressure from 0.005 to 0.3 MPa.
- High pressure. They work under pressure from 0.3 to 0.6 MPa.
Another classification makes it possible to divide all gas pipelines depending on the way they are laid into underground, underwater and land.
What is a gas protection zone and why is it needed
This is a piece of land symmetrical about the axis of the gas pipeline, the width of which depends on the type of gas pipeline and is set by special documents. The establishment of protective zones for gas pipelines makes it possible to prohibit or limit construction in the area where the gas pipeline passes. The purpose of its creation is to create normal conditions for the operation of the gas pipeline, its regular maintenance, maintaining integrity, as well as minimizing the consequences of possible accidents.
There are “Rules for the Protection of Main Pipelines, ” which regulate the establishment of protective zones for various pipelines, which include gas pipelines transporting natural or other gases.
On the territory of the security zone, agricultural work is allowed, but construction is prohibited. Work on the reconstruction of existing buildings, structures and networks should be coordinated with the organization engaged in the maintenance and operation of the gas pipeline. Among the works that are forbidden to be carried out in the security zone, is also the arrangement of basements, compost pits, welding works, the installation of fences that impede free access to pipes, the creation of landfills and storage facilities, the installation of stairs based on a gas pipeline, as well as the installation of unauthorized connections.
Features of the security zone of high pressure gas pipelines
The security zone of the high-pressure gas pipeline of the 1st and 2nd category is equipped equally. Their function is to supply gas to low and medium pressure distribution networks.
- Category 1 high pressure pipelines work with gas under pressure from 0.6 MPa to 1.2 MPa if they transport natural gas or air-gas mixtures. For hydrocarbon gases transported in a liquefied form, this pressure shall not exceed 1.6 MPa. Their security zone is 10 m on both sides of the axis of the gas pipeline in the case of distribution gas pipelines and 50 meters for high-pressure gas pipelines through which natural gas is transported. If liquefied gas is being transported, the security zone is 100 m.
- Category 2 high pressure pipelines transport natural gas, gas-air mixtures, and liquefied gas under pressure from 0.3 to 0.6 MPa. Their security zone is 7 m, and if the gas pipeline is 50 m for natural gas and 100 for liquefied gas.
Organization of the security zone of the high pressure gas pipeline
The security zone of the high pressure gas pipeline is organized by its operating organization on the basis of a project specifying the survey made after completion of construction and issued permits. To maintain it, the following activities are carried out.
- Every six months, an organization operating high pressure gas pipelines is obliged to remind individuals and organizations that exploit land in security zones about the land use features of these areas.
- Each year, the route should be updated and, if necessary, all documentation issued on it should be adjusted. The security zone of the high pressure gas pipeline is being specified accordingly.
- The security zone of the high-pressure gas pipeline is marked on its linear sections with columns located at a distance of not more than 1000 m (Ukraine) and not more than 500 m (Russia), all pipe turning angles should also be indicated with a column.
- The intersection of the gas pipeline with transport routes and other communications must be marked with special plates notifying that there is an exclusion zone for the high pressure gas pipeline. Stopping transport within the designated security zone is prohibited.
- Each column is equipped with two posters with information about the depth of the route, as well as its direction. The first plate is installed vertically, and the other with mileage marks - at an angle of 30 degrees for the possibility of visual control from the air.
Features of the security zone of medium pressure gas pipelines
The security zone of the medium pressure gas pipeline is 4 meters according to regulatory documents. As for high pressure routes, it is installed on the basis of technical documentation provided by organizations - designers. The basis for creating a security zone and applying it to the master plan is an act issued by local governments or executive authorities.
The security zone of a medium-pressure gas pipeline implies restrictions similar to those indicated for high-pressure routes. To perform any excavation work in the security zone, it is necessary to obtain the permission of the organization serving this section of the gas pipeline.
The marking of protection zones for medium pressure is carried out similarly. On the columns there should be signs with information about the name of the pipeline, route alignment, distance from the signs to the axis of the pipeline, the size of the security zone, and telephones for contacting the organization serving this section of the gas pipeline. Shields are allowed to be placed on power transmission towers, communication networks and instrumentation columns.
Features of the security zone of low pressure gas pipelines
The main function of low pressure gas pipelines is to provide gas to residential buildings and structures, which can be either built-in or free-standing. Transportation with their help of a large amount of gas is unprofitable, therefore, large utility consumers do not use such networks.
The security zone of the low pressure gas pipeline is 2 m on both sides of the axis of the pipe. Such pipelines are the least dangerous, therefore, the security zone around them is minimal. Restrictions on its operation are similar to those introduced for security zones of other types of gas pipelines.
The security zone of the low pressure gas pipeline is marked similarly to the two previous ones. If the plates located on the bindings are yellow, then the laid pipeline is made of polyethylene. If it is green, then the pipe material is steel. The plate does not have a red piping on top, characteristic of high pressure pipelines.
Outside gas pipeline security zone
An external gas pipeline is a gas pipeline that is located outside the buildings to the diaphragm or other disconnecting device, or to the case through which the building is underground. It can be located underground, above ground or above ground.
For outdoor gas pipelines, there are the following rules for determining protection zones:
The security zone of the external gas pipeline along the routes is 2 m on each side of the axis.
- If the gas pipeline is underground and made up of polyethylene pipes, and a copper wire is used to mark the route, then the security zone of the underground gas pipeline in this case is 3 m from the location of the wire, and 2 m from the other side.
- If the gas pipeline is built on permafrost soils, then regardless of the material of the pipes, its protection zone is 10 m on both sides of the pipe axis.
- If the gas pipeline is inter-settlement and crosses a woodland or areas overgrown with shrubs, its conservation zone is 3 meters on either side of the axis. They are arranged in the form of glades, the width of which is 6 meters.
- The security zone of gas pipelines located among tall trees is equal to their maximum height so that the fall of a tree cannot cause a violation of the integrity of the gas pipeline.
- The security zone of an external gas pipeline passing under water through rivers, reservoirs or lakes is 100 m. It can be visualized as the distance between two parallel planes passing through conditional border lines.
How to establish a security zone for a particular gas pipeline
The gas pipeline protection zone is one of the territories with a special land use regime. At the same time, for these facilities there is a sanitary protection zone, the rules for the arrangement of which are established by SanPiN 2.2.1 / 2.1.1.1200-03.
According to Appendix 1 to these rules, the sanitary zone of a high pressure gas pipeline depends on the pressure in the pipe, its diameter, as well as the type of buildings and structures with respect to which the distance is calculated.
The smallest sanitary zone from rivers and other bodies of water, as well as water intakes and irrigation facilities is 25 m for gas pipelines of any diameter and type.
The largest protective zone of a high-pressure gas pipeline is necessary if we are talking about a class 1 gas pipeline with a diameter of 1200 mm in cities, summer cottages and other crowded places. In this case, the length of the sanitary zone reaches 250 m.
More detailed data on the sanitary protection zones of the main gas pipelines of natural and liquefied gas can be found in the corresponding tables of this document. For highways transporting liquefied gas, sanitary zones are significantly increased.
Violation of the security zone of the gas pipeline. Legal and environmental implications
Violation of the security zone of the gas pipeline can cause a serious technological accident, a fire or explosion. Their cause may be unauthorized excavation work in protected areas without coordination with the organization serving the gas pipeline, trees falling, car damage.
In the best case, there will be a violation of insulation, in the worst case, cracks and other defects will appear on the pipe, which over time will cause a gas leak. Such defects may not appear immediately and only eventually cause an emergency condition.
Damage to gas pipelines due to violation of security zones is punishable by a large administrative fine, which depends on the degree of damage. Demolition of buildings and structures built on the territory of protected zones is carried out by decision of the administrative court.
Unauthorized excavation, unauthorized planting of trees and shrubs, the organization of sporting events, the location of fire sources, the construction of buildings, the development of sand pits, as well as fishing, the work to deepen or clean the bottom and the installation of a watering hole in places where the underwater section of the gas pipeline passes are punishable by fines 5 thousand rubles.
