3
is a highly established controlled research tool that deter-
mines the impacts of rock-cutting (Dogruoz et al., 2016).
Prior to the rock testing, calibration is done to ensure cut-
ting alignment and force constancy by using standardized
forces at 9 and 45.
Lower-depth cuts, called conditioning cuts, were made
over the surface to reduce the possible influence of horizon-
tal and vertical fractures resulting from the prior rock cut-
tings. These pre-cuts ensure cracks propagate consistently
within the specified penetration and cut depth boundary.
The dust collection exercise was consistently performed
on many of the middle lines, exposing a fresh face of the
sample rather than the lines at the extreme left and right
to avoid collecting concrete dust data. The spacing of the
cutting geometry matrix was maintained at 3 or 4 inches.
The prepared rock samples are placed in a vast metal
casing and placed on a sled whose position was maintained
with the help of hydraulic cylinders attached to the front
and back of the sled, which assist in moving this heavy rock
sample forward and backward for examination. This sled
ensures that the rock sample is placed directly under the
cutting tool. The LCM uses a linear variable displacement
transducer (LVDT) sensor to maintain a constant cutting
speed. LVDT measures the displacement of the sample dur-
ing the test, tracks the rock box position, and verifies cut-
ting speed at every pass. Moreover, the sensor locates the
pick tip and separates cut zones in the rock sample from
concrete cuts to separate data.
Wear Condition Techniques
Two distinct measures were used to determine conical pick
wear dimensions and to discriminate between newly –
moderately worn– and extensively worn picks by using the
weight and radius of the pick. A series of conical picks were
used to analyze each wear state (new, moderately worn, and
completely worn). To generate wear indicative of its speci-
fied stage, each pick was placed in a controlled wear work-
shop at CSM, such as a simulated mining activity, for a
predetermined amount of time. Precision calipers measured
each pick’s diameter at several spots along its length follow-
ing wear induction.
Sample Collection of Dust and Fines
The researchers use a Field Emission Scanning Electron
Microscope (FE-SEM) to analyze a sample of pure coal
dust, determining its elemental composition by X-ray dif-
fraction. The elemental spectrum from this baseline was
then compared with that obtained from filter surfaces
loaded with dust particles. To eliminate interference from
concrete dust, the team removed the excess concrete part
Figure 2. U-92 pick cutters ranging from new (first 3 from
right) to moderately worn out and completely worn out were
used to cut the rock samples
Figure 3. The front and back view of the rock samples after
the concrete has been cut off to avoid interaction with the
pick cutter thereby reducing contamination of the coal dust
samples
Figure 4. Dust collection apparatus with the pumps to
collect samples for FE-SEM imagery using three 10-mm
Dorr-Oliver cyclones for NMAM 7500/0600 concentration
and backup and for particle size distribution and the paper
filter used to collect the fines that remain on the surface of
the rock that is used for particle size distribution
is a highly established controlled research tool that deter-
mines the impacts of rock-cutting (Dogruoz et al., 2016).
Prior to the rock testing, calibration is done to ensure cut-
ting alignment and force constancy by using standardized
forces at 9 and 45.
Lower-depth cuts, called conditioning cuts, were made
over the surface to reduce the possible influence of horizon-
tal and vertical fractures resulting from the prior rock cut-
tings. These pre-cuts ensure cracks propagate consistently
within the specified penetration and cut depth boundary.
The dust collection exercise was consistently performed
on many of the middle lines, exposing a fresh face of the
sample rather than the lines at the extreme left and right
to avoid collecting concrete dust data. The spacing of the
cutting geometry matrix was maintained at 3 or 4 inches.
The prepared rock samples are placed in a vast metal
casing and placed on a sled whose position was maintained
with the help of hydraulic cylinders attached to the front
and back of the sled, which assist in moving this heavy rock
sample forward and backward for examination. This sled
ensures that the rock sample is placed directly under the
cutting tool. The LCM uses a linear variable displacement
transducer (LVDT) sensor to maintain a constant cutting
speed. LVDT measures the displacement of the sample dur-
ing the test, tracks the rock box position, and verifies cut-
ting speed at every pass. Moreover, the sensor locates the
pick tip and separates cut zones in the rock sample from
concrete cuts to separate data.
Wear Condition Techniques
Two distinct measures were used to determine conical pick
wear dimensions and to discriminate between newly –
moderately worn– and extensively worn picks by using the
weight and radius of the pick. A series of conical picks were
used to analyze each wear state (new, moderately worn, and
completely worn). To generate wear indicative of its speci-
fied stage, each pick was placed in a controlled wear work-
shop at CSM, such as a simulated mining activity, for a
predetermined amount of time. Precision calipers measured
each pick’s diameter at several spots along its length follow-
ing wear induction.
Sample Collection of Dust and Fines
The researchers use a Field Emission Scanning Electron
Microscope (FE-SEM) to analyze a sample of pure coal
dust, determining its elemental composition by X-ray dif-
fraction. The elemental spectrum from this baseline was
then compared with that obtained from filter surfaces
loaded with dust particles. To eliminate interference from
concrete dust, the team removed the excess concrete part
Figure 2. U-92 pick cutters ranging from new (first 3 from
right) to moderately worn out and completely worn out were
used to cut the rock samples
Figure 3. The front and back view of the rock samples after
the concrete has been cut off to avoid interaction with the
pick cutter thereby reducing contamination of the coal dust
samples
Figure 4. Dust collection apparatus with the pumps to
collect samples for FE-SEM imagery using three 10-mm
Dorr-Oliver cyclones for NMAM 7500/0600 concentration
and backup and for particle size distribution and the paper
filter used to collect the fines that remain on the surface of
the rock that is used for particle size distribution