The hottest railway construction heavy industry sh

China railway construction heavy industry shield machine "Jincheng No.1" Lanzhou show off

China railway construction machinery information

Guide: on April 1, the first rail transit construction shield machine in Lanzhou history, Jincheng No.1, was hoisted and lowered into the shaft at Shiji Avenue Station in the test section of line 1, and Lanzhou Metro Line 1 entered a new stage of accelerated promotion and construction. Here, it will become the shield starting station and test section of Lanzhou rail transit crossing the Yellow River in the future

on April 1, the first rail transit construction shield machine "Jincheng No.1" in Lanzhou history was hoisted and lowered into the shaft at Shiji Avenue station in the test section of line 1, and Lanzhou Metro Line 1 entered a new stage of accelerated promotion and construction. Here, it will become the shield starting station of Lanzhou rail transit in the future "crossing the Yellow River twice". The shield machine in the test section will also accumulate rich experience for the whole line construction in June this year. 3. If the control mechanism is found to be ineffective. The test section of Lanzhou Rail Transit Line 1 has been officially started since July 9 last year, and the overall progress is smooth. The construction of the whole line is planned to start in June this year and be completed in October 2016. It is reported that after two months of assembly and commissioning, the "Jincheng 1" will break the ground in June, with an initial progress of 10 meters a day. It is expected that the left and right underground lines from Shiji Avenue station to yingmentan station in the test section will be excavated and connected by the end of this year

"Jincheng No.1" is a customized cutter head with a diameter of 6.44 meters, a main control room of about 15 square meters, and a shield tail more than two people high... The parts of "Jincheng No.1" that have not been assembled are first shown on the site of the test section, which is a little confusing. According to the introduction of the municipal rail transit office, the earth pressure balance shield machine used in the test section was specially "customized" by China railway construction heavy industry group Co., Ltd. according to the actual situation of the water rich sandy gravel stratum in the test section of line 1 phase I project, and the design of the cutter head, host structure, equipment layout, operation interface and other aspects was tailored. The total machine length is 84 meters, the main machine length is 13.2 meters, one equipment bridge and six trailers, weighing 508 tons, of which only the cutter head and front shield weigh about 160 tons, and the average tunneling speed can reach 450m/month. The performance parameters of the whole machine have reached the domestic leading and international advanced level. According to relevant sources, the cost of the shield machine is about 40million yuan

at noon on April 1, the "main control room", which is responsible for automatic operation, took the lead in slowly lowering into the well. The cutter head, shield tail and other host equipment will be assembled and debugged in the next two months. It is expected that the shield machine will officially break the ground on June 1 this year. "Jincheng No.1" will be excavated in the two station interval from Shiji avenue to yingmentan in advance, of which the right line of the tunnel is 652 meters long and the left line is 575 meters long. "At the beginning, it is a trial tunneling stage, tunneling is about 10 meters a day, and the right line is planned to be completed by August and September this year." as for the tunneling speed of "ten meters a day", fengshichuan, deputy general manager of Lanzhou Rail Transit Co., Ltd., explained, "Another important significance of shield tunneling in the test section is to make preparations and summaries on operation management, construction technology and geological environment for the commencement of the whole line of phase I project of line 1 on June 1, and to provide feasibility data for later construction." According to relevant construction personnel, the left and right lines of the test section can be basically connected by the end of this year

tunnel excavation one-time forming

what is a shield machine? Figuratively speaking, it is often described as "pangolin" and "earth auger". In fact, its full name is "shield tunneling machine". It is a special construction machinery for tunneling that provides chemical buyers with the choice of developing and producing bio based and carbon emission reducing products. It is now widely used in underground tunnel projects such as subways and railways at home and abroad. The shield machine integrates optical, mechanical, electrical, hydraulic, sensing and information technology, and has the functions of excavating and cutting soil, transporting soil slag, assembling tunnel lining, measuring, guiding and correcting deviation

the main structure of the shield machine includes four parts: cutter head, front shield, middle shield and tail shield. The cutter head is located at the front end of the whole machine, next to the mud and stone to be excavated, and is the "pioneer" of the shield machine. Generally speaking, the working principle of the main body of the shield machine is like a "razor". In the process of moving forward, the full face cutting cutter disc cuts the soil and puts it into the storage compartment behind the cutter disc. When it is excavated, the soil slag is continuously discharged to the ground by the screw conveyor installed at the lower part of the sealing compartment. The screw conveyor projet MJP 5600 allows customers to distribute different material mixtures into different shells in a single part, and master the excavated amount by speed control. The excavated amount closely matches the cutting speed of the cutter head, so as to keep the sealed cabin always full of soil without being too full. In addition, in terms of resistance to collapse and settlement, the "storage room" storage sealed cabin of the shield machine also plays an important role. It can make the cabin have appropriate pressure to balance with the pressure of soil and water conservation on the excavation surface, so as to reduce the disturbance of shield propulsion to the formation soil mass and control the surface settlement

"the shield machine drives forward, and the segments are assembled at the back, and the tunnel is basically formed at one time". A construction personnel on the site said that the shield machine also has the characteristics of high automation, labor saving, fast construction speed, and is not affected by the climate. "The operation is basically automated. There is only one technician in the main control box. In the manual part, the downhole operators need about 60 people, mainly responsible for segment assembly and muck transportation in the shield."

line 1 will use two types of shield machines

"there are basically two types of shield machines that will be used in the phase I project of line 1. At present, the test section under construction starts from the sand gravel layer 6 meters underground. This geology and the current site are more suitable for the use of earth pressure balance shield machines. In the construction section under the Yellow River, mud water balance shield machines will be used." Songweijie, head of the Engineering Technology Department of Lanzhou Rail Transit Line 1 test section project of China Railway 21st bureau group, told, "the service life of a shield machine is about 15 kilometers after the completion of tunneling." Jincheng No. 1 "should also be used in the construction of the next section of line 1 after the construction of the test section."

"the shield technology used in the test section of Lanzhou rail transit is an advanced technology in the country," songweijie said. "In the early stage of subway construction in this sand gravel layer, only Cheng Bu said that Vertu had similar situations and early experience in using empty words such as Ruby bearings and sapphire screens on the flip."

it is noteworthy that the important "two crossing the Yellow River" of Rail Transit Line 1 will start from the shield in the test section in the future. Songweijie said, "the construction node of the test section is from Shiji Avenue station to yingmentan station, and the node of line 1" crossing the Yellow River "is exactly these two ends. One is from Shiji Avenue station to the Olympic Sports Center Station in the west, and the other is from yingmentan station to Matan station in the East. The shield construction of the test section is making important preparations for the next crossing the Yellow River and the commencement of the whole line."