19
RELATED SYSTEMS AND METHOD
SELECTION
Treatment to this point has dealt with system and compo-
nent specifics within the author’s experience. This final sec-
tion will address related material transfer systems and some
overall characteristics on system selection.
Successful aggregate transfer into deep collieries has
been done using hardened steel, lithic (cast basalt), and
ceramic lines. One approach entailed using a converted
shaft, with multiple pipes having open discharge 30 meters
above a likewise open rock box set in the rib of the shaft. The
rails of the rock box or grizzly were spaced to accommodate
desired comminution, while the majority of impacting rock
deflected directly to the bin discharge built above a mixing
plant constructed in the actual shaft bottom.
The multiple drop lines permitted efficient operation
and maintenance cycling of the system as aggregate was
delivered for the mine backfill (1). The ability to accom-
modate multiple lines and operations/maintenance cycling
typically is a strong attraction to shaft installations.
In other fill systems, spiral-cast lines have been used to
transfer aggregate. These lines avoid the material reaching
terminal velocity by guiding the material in essentially full
contact down a spiral surface the full length of the drop.
As with all transfer systems, when the liner is matched well
to the transfer material, the system can be efficient and
successful.
Transfer Raises
A final discussion of transfer types in this paper concerns
passes or raises. Conventional for ore and waste handling,
the technique can be used for uncemented aggregate,
cemented rockfill, and when the circumstance is war-
ranted, even concrete. These systems have been common
for decades across various underground mining methods
(Johnson, et al., 2023).
As the Meikle Mine expanded production and con-
comitant backfill needs, 1.8 m-diameter (6 ft) transfer
raises were used to pass cemented rockfill to lower levels
(1). The raises increased the efficiency of fill delivery above
trucking all the fill through the ramp system. Rings of AR
steel were anchored and poured into the collar of each lower
level intercepted by the transfer raises. Impact plates were
set across the collar rings at the level where fill was sched-
uled, with the plates in levels above removed to clear the
raise. Conventional impact analysis (5) was used in design-
ing the plate and collar ring assemblies. A light and claxon
system was installed at each level to signal pass operation,
with mine phones at each station for direct confirmation
among operators.
CONCLUDING CONSIDERATIONS
Components within slickline and dropline systems are high-
wear and their repair and/or replacement can significantly
impact the overall system. Those overall systems typically
are unique, and rather than detailed analyses of one con-
figuration, the authors have presented a general narrative
of characteristics, many of which can universally influence
life cycles. Those discussions of line design, installation,
operation, maintenance and related systems are pertinent
to a concluding consideration: a salient query being that if/
when components fail, is downtime acceptable or is system
redundancy preferrable?
Though detailed calculations and costs are not pre-
sented here, the suite of discussions lend themselves to pre-
liminary engineering. They can further guide more detailed
analyses in addressing specific mine settings and selecting
appropriate systems. Slickline and dropline systems have
a long history in underground mining, and their use is
expected to continue when appropriate in shaft sinking,
mine development and mine operation.
ACKNOWLEDGMENT
The authors wish to thank Amax, Hecla, Barrick Gold,
Dynatec, Newmont, and Cementation USA. These firms
and friends therein provided opportunities to learn, develop
and successfully practice the concepts through details writ-
ten here. Thanks to Stantec for permission to incorporate
Hard Rock Miner’s Handbook excerpts into an appendix.
Thanks to SME for the opportunity to present this paper.
ABOUT THE AUTHORS
Ralph R. Sacrison, P.E., SME-RM, Sacrison Engineering,
Elko, NV: Personal industry experience since 1976.
Established Sacrison Engineering in 2004 to provide engi-
neering in precious and base metals, coal, uranium and
industrial minerals. Primary service areas are in engineer-
ing, construction management, and project management,
with proven success in mining, geological, hydrological,
environmental and maintenance at surface and under-
ground mines and plants, domestic and international.
1976, B.A. Geology, Colgate University. 1980, M.S.,
Mining Engineering, New Mexico Institute of Mining and
Technology.
Lauren M. Roberts, P.E., Roberts Engineering and
Development, Spokane, WA: He has 35 years of experience
in the global mining industry. Lauren previously worked
for Hecla Mining Company, Kinross Gold Corporation,
Barrick Gold Corporation, beginning his career with
Hecla for the first time in 1989. He graduated in 1988
with a Bachelor of Science degree in Mining Engineering
RELATED SYSTEMS AND METHOD
SELECTION
Treatment to this point has dealt with system and compo-
nent specifics within the author’s experience. This final sec-
tion will address related material transfer systems and some
overall characteristics on system selection.
Successful aggregate transfer into deep collieries has
been done using hardened steel, lithic (cast basalt), and
ceramic lines. One approach entailed using a converted
shaft, with multiple pipes having open discharge 30 meters
above a likewise open rock box set in the rib of the shaft. The
rails of the rock box or grizzly were spaced to accommodate
desired comminution, while the majority of impacting rock
deflected directly to the bin discharge built above a mixing
plant constructed in the actual shaft bottom.
The multiple drop lines permitted efficient operation
and maintenance cycling of the system as aggregate was
delivered for the mine backfill (1). The ability to accom-
modate multiple lines and operations/maintenance cycling
typically is a strong attraction to shaft installations.
In other fill systems, spiral-cast lines have been used to
transfer aggregate. These lines avoid the material reaching
terminal velocity by guiding the material in essentially full
contact down a spiral surface the full length of the drop.
As with all transfer systems, when the liner is matched well
to the transfer material, the system can be efficient and
successful.
Transfer Raises
A final discussion of transfer types in this paper concerns
passes or raises. Conventional for ore and waste handling,
the technique can be used for uncemented aggregate,
cemented rockfill, and when the circumstance is war-
ranted, even concrete. These systems have been common
for decades across various underground mining methods
(Johnson, et al., 2023).
As the Meikle Mine expanded production and con-
comitant backfill needs, 1.8 m-diameter (6 ft) transfer
raises were used to pass cemented rockfill to lower levels
(1). The raises increased the efficiency of fill delivery above
trucking all the fill through the ramp system. Rings of AR
steel were anchored and poured into the collar of each lower
level intercepted by the transfer raises. Impact plates were
set across the collar rings at the level where fill was sched-
uled, with the plates in levels above removed to clear the
raise. Conventional impact analysis (5) was used in design-
ing the plate and collar ring assemblies. A light and claxon
system was installed at each level to signal pass operation,
with mine phones at each station for direct confirmation
among operators.
CONCLUDING CONSIDERATIONS
Components within slickline and dropline systems are high-
wear and their repair and/or replacement can significantly
impact the overall system. Those overall systems typically
are unique, and rather than detailed analyses of one con-
figuration, the authors have presented a general narrative
of characteristics, many of which can universally influence
life cycles. Those discussions of line design, installation,
operation, maintenance and related systems are pertinent
to a concluding consideration: a salient query being that if/
when components fail, is downtime acceptable or is system
redundancy preferrable?
Though detailed calculations and costs are not pre-
sented here, the suite of discussions lend themselves to pre-
liminary engineering. They can further guide more detailed
analyses in addressing specific mine settings and selecting
appropriate systems. Slickline and dropline systems have
a long history in underground mining, and their use is
expected to continue when appropriate in shaft sinking,
mine development and mine operation.
ACKNOWLEDGMENT
The authors wish to thank Amax, Hecla, Barrick Gold,
Dynatec, Newmont, and Cementation USA. These firms
and friends therein provided opportunities to learn, develop
and successfully practice the concepts through details writ-
ten here. Thanks to Stantec for permission to incorporate
Hard Rock Miner’s Handbook excerpts into an appendix.
Thanks to SME for the opportunity to present this paper.
ABOUT THE AUTHORS
Ralph R. Sacrison, P.E., SME-RM, Sacrison Engineering,
Elko, NV: Personal industry experience since 1976.
Established Sacrison Engineering in 2004 to provide engi-
neering in precious and base metals, coal, uranium and
industrial minerals. Primary service areas are in engineer-
ing, construction management, and project management,
with proven success in mining, geological, hydrological,
environmental and maintenance at surface and under-
ground mines and plants, domestic and international.
1976, B.A. Geology, Colgate University. 1980, M.S.,
Mining Engineering, New Mexico Institute of Mining and
Technology.
Lauren M. Roberts, P.E., Roberts Engineering and
Development, Spokane, WA: He has 35 years of experience
in the global mining industry. Lauren previously worked
for Hecla Mining Company, Kinross Gold Corporation,
Barrick Gold Corporation, beginning his career with
Hecla for the first time in 1989. He graduated in 1988
with a Bachelor of Science degree in Mining Engineering