Major breakthrough Taiyuan subway will use local made shield machine
major breakthrough Taiyuan subway will use local made shield machine
China Construction machinery information
line 2 is the first subway line in Taiyuan. For most citizens, everything about subway construction is attractive. At present, Metro Line 2 is about to enter the main construction stage of the station. Soon, a big guy who can dig holes underground will be used in the construction of the interval tunnel between stations. This is the shield machine specially used for tunneling. It is often vividly called the underground pangolin. It is a large body weighing 450 tons. It can eat soil in front of it and dump soil behind it. On average, it can dig 10 meters underground every day, which is much more efficient than manual excavation. More importantly, the shield machine to be used in the construction of Metro Line 2 in our city is completely manufactured in Taiyuan, filling the gap in the manufacturing of high-end underground equipment in the province
what is the magic of this shield machine? Compared with the previous introduction or even import from other provinces, what are the advantages of local manufacturing? Yesterday, I walked into Taizhong steel rolling equipment branch to explore the truth and uncover the mystery of the underground pangolin for you
a single "weight" of 450 tons
entering the plant area of Taizhong steel rolling equipment branch, a long and large machinery quietly "lying" aside, marked with the words "Longcheng No. 1". "This is the first shield machine produced and manufactured in Taiyuan. It is specially developed for the construction of Taiyuan subway. It has been successfully rolled off the production line and will soon be used in the tunnel construction of the Central Street West Station in the first section of line 2 phase I project." Gaozhiyu, director of the assembly department of the straightening machine factory of Taizhong steel rolling equipment branch, introduced that the shield machine is one of the most important large-scale machinery in subway construction. It is a comprehensive tunneling equipment with multiple functions, and is known as the "king of engineering machinery"
he said that China has completely relied on imports of shield machines for many years, and it was not until 2008 that the monopoly of foreign shield machines in the domestic market was broken. However, at present, only a few provinces in China, such as Changsha, have the capacity to produce and manufacture. If the shield machine from other provinces is used in the subway construction in our city, the weight of one machine will reach 450 tons. The transportation cost is too high, and it has become the first choice
in this case, Taizhong group has built a plant of 30000 square meters in the Taizhong Railway Industrial Park, and introduced a number of domestic and foreign high-end equipment to create various production conditions for the production of shield machines. In October this year, the first shield machine made entirely in China was successfully rolled off the production line, and the contract price of each machine was only one third of that of imports
each has 138 "steel teeth"
approach and carefully look at the first shield machine offline. The total length of the fuselage is 84 meters, which is equivalent to eight 10 meter long buses. The weight of the whole body is almost equal to more than 200 off-road vehicles with a dead weight of 2 tons, which are "customized" for the subway construction in our city
"in the whole fuselage, the heaviest cylinder is the front cylinder, which is mainly used to check whether the material meets the specified standards and study the performance of the material. The diameter of this nose is 6.4 meters, more than 300 tons." According to Gao Zhiyu, in the "family" of shield machines, this size is small. The size of the shield machine varies according to its use. For example, in the tunneling of double track railway, a large head with a head diameter of 12.5 meters will be used, and the excavated tunnel is also larger
"look, this' pangolin 'can chew stone and soil, all thanks to these sharp' steel teeth '." Gao Zhiyu pointed to the red rotating cutter head on the machine head and said that the black hard blocks distributed on it are welded alloy blades, which are all made of manganese steel and have very high hardness. 138 such "steel teeth" are distributed on a shield machine. Just as human teeth are divided into incisors, fangs, molars, etc., the blades on the same shield machine are also different, which can be divided into shell knives, cutters, fishtail knives, etc. it is these blades that "work together" to make circular tunnels under various soil conditions
not only that, if you encounter particularly hard rocks, in case any "tooth" is worn out, you can replace it with a new one
how is the tunneling of shield machine completed? In fact, its working principle is somewhat similar to that of an electric razor. When working, it relies on six main motors to generate power. The jack in the fuselage can provide huge push 8. Thermoplastic force. While pushing forward, it rotates the cutter head to continuously rotate and excavate, and a circular tunnel will be formed underground
many people are curious: where is the soil excavated in the narrow tunnel? The rear part of the shield machine is the frame, and the excavated earth needs to be transported to the rear carriage by the upper belt. Through the temporary track in the tunnel, the excavated earth is transported to the small rail transport vehicle to the foundation pit, and then hoisted to the ground and transported away by car. Figuratively speaking, it is like a big "earthworm", where soil is "eaten" from the front and then discharged from the back
of course, the function of the shield machine is not only this, but also the simultaneous installation of shield segments. During the tunneling, the shield machine will automatically assemble segments on the surrounding tunnel wall and synchronously inject grout. The shield machine will dig out a large hole with a diameter of 6.4 meters. Each fan-shaped segment assembled on the surrounding tunnel wall is 0.3 meters thick, and each group of 6 segments can form a round tube shape, supporting the soil and water around the tunnel and avoiding soil collapse
there are bolts on the segments, which is enough to ensure that the segments in the subway tunnel are connected and linked after biting, and the annular subway tunnel will be formed at one timeIt is reported that the shield machine can work 24 hours a day without stopping, with an average of about 10 meters per day. Only one person is needed in the operation room, and several others cooperate, which saves both labor and time
generally speaking, the service life of this kind of shield machine is 10 kilometers, so a subway tunnel section will be equipped with one. When the specified mileage is reached, it is necessary to stop for maintenance, and some worn parts need to be replaced
"this kind of shield machine has a wide range of uses. In addition to repairing the subway, it can also be used in the construction of underground comprehensive pipe gallery. It is preliminarily estimated that 17 such shield machines are required for the phase I project of Metro Line 2. At present, the first one has been offline and delivered, and the second one is in the commissioning stage. Another 6 have been ordered and are expected to be delivered next year." Gao Zhiyu said that the production time of a shield machine is about 5 months. Due to its "size", the shield machine will be "broken into pieces" when it is transported from the production plant to the subway construction site. It will be disassembled into multiple parts and transported to the construction line by multiple heavy trucks, and then assembled and debugged on site. Generally speaking, it will not be used until the main structure of the station is basically completed, that is, the Research Institute will become the front-end market and the connector developed by the back-end will start the interval construction. Because at this time, the construction site can free up enough space for "big guys" to show their "fists and feet"
for Taizhong group, the successful completion of the first shield machine marks that Taizhong Group officially has a high-end underground construction equipment manufacturing base, and also marks that our province has the ability to locally develop and produce shield machines