9.6: Specific Energy

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For the cases as described above, cutting with a straight blade with the direction of the cutting velocity v_c perpendicular to the blade (edge of the blade), the specific cutting energy E_sp is:

\[\ \mathrm{E}_{\mathrm{sp}}=\frac{\mathrm{F}_{\mathrm{h}} \cdot \mathrm{v}_{\mathrm{c}}}{\mathrm{h}_{\mathrm{i}} \cdot \mathrm{w} \cdot \mathrm{v}_{\mathrm{c}}}=\frac{\mathrm{F}_{\mathrm{h}}}{\mathrm{h}_{\mathrm{i}} \cdot \mathrm{w}}\tag{9-34}\]

The specific energy of the Flow Type of cutting mechanism can be written as:

\[\ \mathrm{E}_{\mathrm{s p}}=\lambda_{\mathrm{H F}} \cdot \mathrm{c}\tag{9-35}\]

The specific energy of the Curling Type of cutting mechanism can be written as:

\[\ \mathrm{E}_{\mathrm{s p}}=\lambda_{\mathrm{H} \mathrm{C}} \cdot \mathrm{c}\tag{9-36}\]

Appendix X: Hyperbaric Rock Cutting Charts: Contains graphs for blade angles from 30 degrees up to 120 degrees, covering both dredging and offshore drilling applications.