Introduction to Shield Cutting Tools (Part 1)

source：http://www.xrocktools.com/ Release Time：2015-01-11 09:57:47

1. Cutting tool

The shape and layout of the main cutting tool of the cutting blade shield machine for cutting the soil on the excavation face will have a significant impact on the excavation effect. The cutting blade will excavate the soft soil layer or the crushed slag soil by the rolling cutter through the cutting blade and scraper, and the slag will enter the slag groove with the front of the cutting blade and scraper. Therefore, the cutting blade and scraper have both cutting and loading functions.

2. Advance knife (advance knife)

As the name suggests, a leading tool is a tool that first cuts soil. In the design of a leading tool, it is mainly considered to work in conjunction with the cutting tool. When the tool cuts soil, the leading tool first cuts the soil before the cutting tool cuts it, dividing the soil into blocks and creating good cutting conditions for the cutting tool. According to its function and purpose, the cross-section of the leading tool is generally smaller than that of the cutting tool. The use of advanced cutting tools can generally significantly increase the flowability of the cutting soil, greatly reduce the torque of the cutting tool, increase the cutting power of the tool, and reduce the wear of the cutting tool. The effect is very obvious when used in loose and loose sand and gravel formations.

3. Shell shaped knife

The disc shell type cutter is essentially an advanced cutter. When a shield tunneling machine passes through sand and gravel formations, especially large particle sand and gravel formations, if a rolling cutter type cutter is used, due to its loose nature, it will produce significant deformation under the excavation and compression of the rolling cutter, greatly reducing the cutting effect of the rolling cutter, and sometimes even losing the ability to cut and break. Using a disc shell type cutter, arranged on the front end face of the cutter disc, is specifically designed for cutting sand and gravel, which can better solve the problem of cutting soil (sand and gravel) by the shield tunneling machine.

4. Fish tail knife

Using a large blade to cut the entire cross-section of the soil, cutting tools are arranged at different positions on the blade. From the outer circumference of the blade to the center, the movement circle gradually decreases, and the center point can theoretically be considered as zero. The corresponding soil flow state is also getting worse and worse. Moreover, cutting blades cannot be arranged at the central support part (with a diameter of about 1.5 m). To improve the cutting and mixing effect of the soil in the central part, a larger fish tail blade can be designed at the central part.

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