Maintenance Downtime controls
The dispatch computer also stores vehicle maintenance records. In-vehicle engine-and transmission-monitoring devices continually report any out-of-range readings, such as high oil temperature. The system notifies the dispatch operator of the problem when it occurs, storing the time-stamped information in the database. Office or
maintenance personnel can poll the trucks or shovels at any time to
determine current operational status.
“Proximity decision” too could be achieved with the GPS data. In this technique, “virtual beacons” are created for key mine locations, benches, dumps, crushers, workshops, haul road intersections etc. Virtual beacons is a database entry that contains the “X” and “Y” coordinates of a location and let the system know when the equipment enters or leaves the location area. Network data of virtual beacons is stored in local memory on-board the mobile equipment. During the course of movement, GPS receivers continually change the positional data and whenever the equipment enters or leaves the “virtual beacon” (circle of influence),- board communication processor notifies the central computer, which then
uses the data in its equipment assignment decisions.
Maintenance management
- Work order administration
- Service schedules
- Maintenance reporting
- Major component tracking
- Repair & defect analysis
- Allocation of resources
- Priority setting
Benefits from the system
- Higher productivity
- Better turnaround of HEMM
- Optimum spare part management
- Operator performance guide
- Production scheduling
- Pit development recomputations
- Optimal traffic flows in the pits
- Hot seat exchange and shift change mgmt
GPS in US coal mines …. & india
Caterpillar Company had developed prototype Computer Aided Earthmoving System (CAES) including on-board display of the excavator/shovel and also the mine operational bench in the geological plan of the mine area. Real Time Kinematic-GPS (RTK_GPS) aided positional data is dynamically displayed on the mine plan and thus aids in locating the shovel on the selected bench, upto centimeter accuracy. Advanced versions even show the plan view in colour and indicate the volume/quantity that has to be removed or filled. Display of the profile too is enabled alongside on-board computer. As the machine works, terrain updates, using GPS
technology, are collected and transmitted back to the office, where
the entire data is monitored. Operations of a number of such
equipment can be monitored at the office. Immediate production
calculations are facilitated at the office as well as the conventionally
developed computerised mine plan updated simultaneously.
Location of drilling machines can be precisely done with the RTK-GPS that are mounted together with the on-board graphic console for drill operator’s guidance. The console displays “virtual”
drilling pattern, using pre-determined blast hole coordinates in the
systems database. The computerised mine plan in the on-board
system also aids in displaying the vertical profile of the geology of
the area and thus indicate the drill hole advancement/intersection
of the sub-surface stratum as the drilling progresses.
DGPS machine control in opencast mines would enable improvement in mine productivity and efficiency. High precision
GPS systems can support an unlimited fleet of mine equipment and
by monitoring the entire fleet from an office centrally located,
better control can be established and even decisions transmitted to
the on-board graphic consoles. Certain modules on equipment
maintenance/condition monitoring too could be simultaneously
stored in equipment system for productivity versus expected real
time consumption for the mining task attached to that equipment;
thus assisting in the day-to-day mine production planning.
India’s coal production is expected to double at 600 million tonnes in the next decade and to realise this impressive growth, optimum utilisation of modern technologies like geographic
information services (GIS) and global positioning systems (GPS) in all facets of mineral exploration are essential. The government is urging the industry to make efforts for increasing use of GPS technology for locating new mineral resources and improved scientific planning for exploitation of natural resources and better
management systems. GPS is being used extensively inbench height
control, drill elevations, topographic surveys and geological mapping
in Indian coal mines.
GPS based Truck Despatching Systems, have been introduced
recently at Gevra Opencast Project (SECL) , West Bokaro Collieries
(TISCO) ,and Northern Coalfields . Based on their performance,
the same is being replicated in other big opencast coal mines in India
notwithstanding the fact that it is a capital intensive project . What
perhaps needs to be encouraged is that the spirit behind the use of
GPS applications must be viewed as beneficial to the coal company
and in turn , to the coal miners themselves.
Conclusions
GPS is a powerful surveying tool, which can provide on its own or in
combination with other ground survey technique the required speed,
accuracy and economy in surveying of large mining or opencast
blocks.
However, the GPS based real-time optimization of HEMM
deployment in opencast mines typically works well within a strict
set of conditions. Production interruptions can have a significant
impact on overall performance. In a coal mine, these interruptions
include shift changes, scheduled and unscheduled maintenance, events
like shovel breakdowns or servicing, lunch breaks, and numerous
other routine events that are all part of a typical shift. An added
complication is variability in data integrity. The loss of a truck’s
GPS or radio antenna can make it invisible to the system, creating
a situation where assignments for other trucks are made without
considering the location and status of the non-reporting truck.
Bibliography
- Annual Report, 1999-2000, Ministry of Coal, Govt. of India
- Speeches (2000), Hon’ble Union Minister of Coal, Govt. of India
- GIS@development , Nov-Dec 1998 issue.
- C.D.Rawling, Chairman, Australian Coal Assn. , Symposium papers, Nov 1997, Australian Academy of Science & Tech.
- Kophie Van Proceedings, Hanover , Spring 1999. Coal facts, World Coal Institute , 2000.