1. Preparations for shield machine assembly are ready
& nbsp; & nbsp; Before the assembly of shield machine, it is necessary to set up a platform and lay steel rails to facilitate the assembly of shield machine into the shaft.
2. The trolley goes down the well
& nbsp; & nbsp; After the trolley and long screw go down the well, pull it back to the designated position with the winch, connect the bridge to go down the well, place it on the pallet truck, and weld and fix it. Remove the temporary track, sidewalk slab and support, and prepare the lower shield.
3. Shield under the bracket
& nbsp; & nbsp; & nbsp; Lower the middle shield, reverse the middle shield by 90 degrees, and use a 400 ton crawler crane to adjust it to a fixed position in the departure shaft. Make simple tooling, one end is fixed on the bracket with bolt holes, and the other end is welded on the middle shield. The pump station is connected with the oil cylinder with the same stroke and pushed along the tunnel axis, so as to ensure the horizontal and lateral fine adjustment of the middle shield.
4. Qiandun downhole
Before the front shield goes down the well, first install the labyrinth ring and then fasten it with bolts. The front shield is hoisted and rotated by 90 degrees, then lowered into the well and placed on the departure bracket.
Before the front shield and the middle shield are connected, the sealing ring is installed and fixed with grease. During installation, align the locating pin, adjust the position of the middle shield, insert the locating pin and fasten the bolt. The middle shield and front shield are connected.
5. Install the bracket of the assembly machine
Remove the scaffold of the tunnel portal, push the connector of the middle shield and the front shield forward, and the front shield enters the second layer of rubber cord fabric. Screw machine, connecting bridge and No. 1 trolley move backward under the action of winch to maximize the installation space and distance. Lift the bracket of the assembly machine to the launching shaft and install it in place.
6. Installation and assembly machine
Transfer the assembly machine into the departure shaft for installation and connection of the assembly machine.
7. Shield tail downhole
For the welding of shield tail brush, remove the binding steel wire after welding. Before hoisting, the hinge seal shall be cleaned. Cut off the processing and welding auxiliary bench, and grind the welding parts flat. During hoisting and transportation, pay attention to the protection of adjusting screws. When connecting with the middle shield, pay attention to hinge sealing and emergency airbag protection. Weld the remaining shield tail brush.
8. Threading machine
Extend the track, set up the platform, introduce the track into the bracket, and use the winch to transport the screw machine to the designated position. Use truck crane, feed screw machine, and connect tail shield, middle shield and front shield. Check the sealing device and install the sealing ring. Make the screw machine and the front shield connected normally.
9. Install the reaction frame
Determine the position of the reaction frame according to the launching scheme. Embed the reaction frame positioning steel plate in advance and set out accurately. Hoist the reaction frame and fix and weld it.
10. Connecting trolley 1, trolley 5 and trolley 3
11. Installation of cutter head
Move the front, middle and tail shields to the specified position to leave enough space for the cutter head. The effective distance from the cutterhead to the portal shall not be less than 170 cm. The effective distance on the left side is 170 cm and the effective distance on the right side is 178 cm. 120t truck crane lower the cutter head. Use the hoisting point of the cutter head to adjust the cutter head into the shaft for connection.
Pay attention to the installation of internal and external sealing strips of cutter head and soil bin, the sealing of cutter head and central swivel, the conversion of central auxiliary force transfer block and force transfer block, and the installation torque, sequence and method of high-strength bolts.
12. Pipeline connection
Before connecting the pipe, check the pipe fittings first to remove the sundries and ensure the cleanness of the inside of the pipe. Apply grease manually with shield tail brush.
Coat the shield tail with grease.
The shield tail grout stop plate is bolted and fixed.
13. Layout and power transmission of high voltage power line
The high-voltage power line shall be laid. After high-voltage power transmission, the transformer shall be unloaded for more than 12 hours.
14. Commissioning
Commissioning of electrical system, mechanical system, water circulation system (external circulation and internal circulation), compressed air system and lubrication system.
Commissioning of six sealing systems: cutter head and earth bin seal, cutter head and rotation center seal, middle shield front shield seal, passive hinge seal, shield tail seal, screw machine and front shield seal. Bentonite and foam system is debugged.
After the commissioning of all system divisional and subdivisional works is completed, the joint test run shall be carried out.
15. Assembly of negative ring segments
Place two rings of segments on the segment truck in advance. According to the gap between the segment and the shield tail, weld the cushion block and assemble the segment according to the point position. After the first ring segment is assembled, the segment shall be welded and fixed with T-block and I-block. Push the negative ring in.
16. Emergency material reserve, condition acceptance, portal removal and shield departure.
