Research on the Coal Seam Permeability-Increasing Technology via High-Pressure Water Jet Reaming and Its Application

<table class="figure-group"><tr class="fig-image" id="a"><td><object data="https://static-preview.hindawi.com/articles/geofluids/volume-2021/6647500/figures/6647500.fig.006a.svgz" name="6647500.fig.006a" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(a) </b>Center bit</td></tr><tr class="fig-image" id="b"><td><object data="https://static-preview.hindawi.com/articles/geofluids/volume-2021/6647500/figures/6647500.fig.006b.svgz" name="6647500.fig.006b" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(b) </b>High-pressure drill pipe</td></tr><tr class="fig-image" id="c"><td><object data="https://static-preview.hindawi.com/articles/geofluids/volume-2021/6647500/figures/6647500.fig.006c.svgz" name="6647500.fig.006c" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(c) </b>Quick coupling</td></tr><tr class="fig-image" id="d"><td><object data="https://static-preview.hindawi.com/articles/geofluids/volume-2021/6647500/figures/6647500.fig.006d.svgz" name="6647500.fig.006d" type="image/svg+xml"></object></td></tr><tr class="fig-caption"><td><b>(d) </b>High-pressure hose</td></tr></table>

<div>Main components and physical drawing.</div>

Geofluids

fig6

Figure 6

Figure 6: Research on the Coal Seam Permeability-Increasing Technology via High-Pressure Water Jet Reaming and Its Application 