The report's author — Alexander "Russos" Popov
About how to produce gas, I told you the example of
"Gazprom" has completed the construction of autumn II thread main gas pipeline "Gryazovets — Vyborg" the 680 km (as the built
Most of the way of the gas pipeline passes through forested areas. Half of the road generally goes through the swamps, which are among the most complex areas of construction. And in the Vyborg district, Leningrad region around fifty kilometers passes through the rocks, which are also the least complicated. Here I want to add that the light areas in the construction of gas pipelines do not exist. Everywhere has its own nuances, subtleties and tricks.
Let's take a look at the final stage of construction, which took place in the Leningrad region: strong rock in the town of Vyborg and microtunnel under Saimaa Canal. All work carried out "Gazprom Invest West."
1. Construction of the pipeline was carried out in different geographical conditions and you may say, every day the team came to a new job. Therefore, the entire building complex was to be mobile and work everywhere, providing new board feet welded pipe. How did this happen?
2. If in the normal development of the trench soil is not a problem, in the swamp of such involve a number of difficulties, and the development of rock in general has to be carried by drilling and blasting. To do this, on the highway of the future trench drilled holes (holes in the rock), in which the charges are laid.
3. Then the trench free from the remnants of rock and leveled the bottom. Then, before the pipe, make a sandy base. Along the route laid out pipe. By the way, this product is famous for its unusual design of modern plant for production of large-diameter pipes "Height 239" Rolling Plant.
4. They call themselves linesmen — they make only the linear part of the pipeline, leaving gaps at the intersections of roads and other utilities. For such sites, there are other specialized teams: explosive teams and brigades prokolschikov — they work on transitions under w / e and roads, as well as water obstacles.
5. Let's look at the main stages of the welding line pipe. In the photo you can see the mobile complex — mobile welding column, complex orbital automatic / automatic welding of pipes.
6. It all starts with the preparation of the joints that with conventional grinders are stripped to bare metal.
7. In the initial position is a centralizer — A device that centers the edge of a new pipe with a ready plot line. Spreads With zhimkov centralizer arranged symmetrically along the circumference, tubes fixed relative to each other, thus exhibiting the desired gap between the edges required for welding the root layer.
8. The prepared pipe layer pipes are posted in the installation position with sling-soft towels, excluding damage to the insulation coating plant. In the photo you can see a very short piece of pipe — a transitional knee, which has a different thickness of the walls at the ends. At this point of the thread will flow stream (which is now taken to the side) and the draft tube is used with a thicker wall.
9. Classic pipelaying — still the main means of mechanization in the construction of the pipeline. This is in addition to advanced welding systems and other cool gizmos.
10. Mounted a new section of the pipeline.
11. Pipe installation and alignment of edges with non-impact expander device — a centralizer.
12. After installation of the pipe joint to drop the welding station — a tent that hosts the welding and auxiliary equipment, as well as individual lighting and a forced-air ventilation. In addition, the work can be carried out in a tent at any time of the year, preventing the ingress of precipitation and the effect of wind on the weld.
13. This first complex (root) mechanically suture performed in protective gas, which increases the welding speed is more than three times compared to the manual method and improves the quality of the weld.
14. After welding the root layer fo
rmed by the reverse roller inspected inside and, if necessary, cleaned unacceptable defects — podvarivayutsya place with acceptable offsets edges that could not be correct in using the internal centralizer.
15. And the outside layer of the root weld is prepared for automatic welding.
16. Further to the joint set automatic orbital welding head (one on each side). Welding filler and cover layers of weld runs in fully automatic mode — a welder operator monitors only the movement of the carriage on the joint and adjust the depth of penetration to better fill the joint. Typically, each tent is one pair pass. In this complex there are four tents.
17. Ready pipeline. After the completion of all the welds are checked by NDT methods, such as flaw detection.
18. All employees of the area are living in a hostel in Vyborg, and at their place of work brings vahtovka. It also gives them lunch and serves as a dining room.
19. Most of the works in "Gazprom" for many years. These people were building gas pipelines in all corners of our country.
After inspection of the site I was taken deep into the Karelian Isthmus. The road winds along the Saimaa Canal. As long as we go, you can enjoy beautiful views of nature or enjoy the canal that runs parallel to the road. But not for long. The next section — under microtunnel
20. Microtunnel being constructed using a tunnel boring mechanized complex Herrenknecht AVM-2000D.
21. Here, everything is in a large tunnel construction, except that the jacks are not on board, and in the mounting chamber depth of 21 meters.
22. A driver sits in a booth on the surface — on a shield for him there is no room.
23. The tunnel consists of prefabricated concrete pipe length of 3 m and an outer diameter of 2.5 m Design lining is designed for a combination of maximum loads of earth pressure and impermeable to water. Since the pipe sections are pressed, the gap between the building and the lining of a special breed of injected lubricant that facilitates the promotion of the finished tunnel.
24. Shield itself — an underground ship, which is equipped with various equipment for the job. Including — navigation, to negotiate on a given track. Compared with the shield, which is built underground, it is very crowded. Development of the breed is a gidroprigruzom, and, accordingly, the complex is equipped with pumps for pumping bentonite and clean it on the surface.
25. Jacking station located in the starting pit, can not provide the full length of punching the tunnel (which is 250 meters). Therefore, in 50-70 meters installed additional jacking sections that dodavlivayut shield with concrete lining.
26. Laser theodolite set in the mounting chamber provides precise guidance of the shield on the highway. Beam falls on a special plate at the bottom and on the deflection of the beam at it you can see in which direction deviated complex.
27. On the other side is cooked and ready for rolling out a whip microtunnel working gas.
As part of a small photo essay is impossible to cover all the 680 kilometers of pipeline and tell in detail about all the features of its construction. But a visit to the two objects during the day and already gives an idea of the complexity of construction, and reveals little niceties the linear part.