Remanufacturing Shield Machine Creates Record of Monthly Tunneling in Northeast China

On August 4, 2017, China Construction Communications "China Construction No. 2" remanufacturing shield machine successfully completed the 974-meter tunneling task on the BT08 tender section of Changchun Metro Line 2 and passed through safely and smoothly.

It is reported that the shield machine has served on the Beijing Metro Line 4 and Shenyang Metro Lines 1 and 2 successively, and the excavation mileage and service time all reached the design life limit. Under the assistance of the Beijing Shield Engineering Association, the China Construction Transportation Shielding Division organized an expert to evaluate the feasibility of remanufacturing the shield machine and concluded that the shield machine cutter, main drive bearing, center rotary shaft, and main drive The damage of key components such as seals and hydraulic cylinders mainly occurs on the surface, and can be remanufactured through advanced and applicable remanufacturing technology represented by surface engineering. After more than three months of hard work by various professional and technical teams, the remanufactured shield machine was completed according to the reconstructed remanufacturing scheme. After the whole machine is installed and debugged, the functions and performance indexes of the re-manufactured shield machine meet or exceed the prototype new machine targets. After passing the inspection and acceptance by the experts, the shield machine was started again under the BT08 tender section of Changchun Metro Line 2. The performance parameters such as speed, thrust, and cutterhead torque were stable during the tunneling process, and grouting, foam, and belt conveyors were used to assist. The system is running well, all reaching the new machine performance index, creating the highest monthly record for the monthly tunneling of the subway shield in the Northeast, and demonstrating the good performance of the remanufactured shield machine with excellent excavation efficiency. At the same time, due to greatly improved operational reliability, the remanufactured shield machine has a prominent power-saving effect.

It is estimated that the use of "China Construction No. 2" remanufactured shield machine can save more than 20 million yuan of capital and save more than 200 tons of steel compared with the new model of the same type of shield machine. The economic and environmental benefits are significant. (This article comes from the Department of Energy Conservation and Comprehensive Utilization of the Ministry of Industry and Information Technology)