Wear Issues in the Screw Machine of Shield Tunneling
Problem Description
During shield machine excavation, the screw machine is used.
The blades are rotated inside the soil bin.
As a result, the slag inside the bin causes continuous wear on the blades.
Wear-resistant treatment must be applied to the part exposed from the soil bin.
When slag enters the screw machine barrel, it changes from a scattered state to a gathered state.
Because of this transition, heavy wear happens at the barrel’s front section and the blades inside.
If no preventive measures are taken, serious problems may occur:
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Performance parameters of the screw machine will be reduced.
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The soil discharge rate will decrease.
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The shield machine’s excavation speed will be slowed down.
Solution Proposal
To solve this issue economically, surfacing of wear-resistant materials is recommended.
Wear-resistant materials with about 5 mm thickness should be applied to:
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The outer surfaces of the blades.
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The blade panels.
With this method:
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Friction will be buffered when the blades face slag wear.
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Good wear resistance will be achieved.
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Surfacing materials will be saved.
Thus, the screw machine’s working life will be extended, and excavation speed will be maintained.
