1、 Remove the cutterhead from the host

1. Preliminary cleaning of the solidified slag and residual soil accumulated in the soil bin on the surface of the cutterhead;

2. Weld lifting rings (ears) according to the position of the center of mass of the cutterhead for lifting and flipping;

3. Remove the connecting bolts, nuts, and pin shafts on the flange after disassembling the cutterhead and drive device; Use large lifting equipment to lift and separate.

2、 Blade cleaning, cleaning, and disassembly

1. Clean the residual soil on the surface of the cutterhead, cutting tools, etc.; Clean and rinse with clean water or oil; After drying, check and record the relevant dimensions and appearance;

2. Disassemble the cutterhead according to the characteristics of the components and store it in a fixed area by category;

3. Disassemble the central rotary joint, place the cutterhead flat (with the flange surface below) and support it, then disassemble the tool; Then disassemble the profiling knife and pipeline; Finally, disassemble and inspect the injection hole and related pipeline accessories.

3、 Comprehensive evaluation of components

For the cutterhead, the components that need to be evaluated for remaining life mainly include the central rotary joint and the profile cutter hydraulic cylinder. The second is to study the similarities, differences, and effects of the same tool failing at different locations and different tools failing at the same location, and analyze the reasons and mechanisms.

4、 Determine the remanufacturing plan

By evaluating the remaining life and analyzing the failure mechanism, combined with the measured data during the component decomposition process, the basic technical scheme and principle for remanufacturing each part of the cutterhead can be determined. For hard rock, soft soil, and composite cutterhead structures, there are significant design variations based on the requirements of geological conditions. For example, welding overlay, surface treatment, shaping, machining and other methods can achieve remanufacturing, restore geometric dimensions, and ensure overall strength requirements. For cutting tools, high-performance welding materials can be used for surfacing and surface treatment; For blade connectors, fasteners, and other parts, they can be cleaned, maintained, and inspected thoroughly. For hydraulic cylinder seals, hydraulic hoses, grease pipes, and pipe joints, they should be replaced with new ones and subjected to performance testing.

5、 Key Performance Test of Knife Disk

The assembly process of the cutterhead is the same as that of new parts, with a focus on key dimension inspection and performance testing of important components.

1. The coaxiality position error between the cutterhead and the front cover.

2. The key dimensions of the cutterhead include the distribution radius of the tool path (tool distance), blade height, tool crown, tool height difference, cutterhead structure diameter, cutterhead excavation diameter (theoretical/actual), and wear-resistant layer thickness.

3. Arrangement of cutting tools, number and size of tooth shaped cutting tools and scrapers, arrangement of gauge cutting tools, extrusion trajectory of disc-shaped rolling cutters on hard rock surfaces, and stress angle of rolling cutters. Ensure the size of the opening rate in the soft soil layer and place a mud cake cutter; When the dental crown of the tooth cutter penetrates, increase the number of teeth cutters on the same trajectory during the grinding process; Arrangement of composite disc cutters, gear cutters, and scrapers; The height difference of hard rock disc cutters and the arrangement of cutting tools; The surface of the hydraulic cylinder of the imitation knife should be free of wear, scratches, pits, and bending deformation. The auxiliary pipeline should be unobstructed, and there should be no leakage at the joints and seals. Testers should promptly record various measurement and testing data.