The unsung heroes of underground mining are not the giant machines, but the humble utility vehicles that transport personnel, equipment, and supplies to the farthest reaches of the mine, thereby keeping the mine operations run smoothly and efficiently.
by Harshvardhan Singh
In underground mining, efficient and safe transportation of people, materials, and equipment is critical to operational success. Traditional methods, such as shafts, track/rail systems, and trackless systems, each come with notable disadvantages, including high costs, inflexibility, time inefficiencies, and maintenance challenges. Utility vehicles (UVs) have emerged as a superior alternative, offering greater versatility, mobility, and cost-effectiveness.
Unlike shafts, UVs reduce reliance on complex hoisting systems. They outperform track systems by adapting to changing mine layouts without the need for extensive infrastructure, and they address the limitations of trackless systems by providing tailored solutions with lower maintenance and fuel requirements. This article explores the importance and benefits of utility vehicles in underground mining, highlighting their transformative impact on productivity, safety, and operational efficiency.
MOBILE WATER SPRINKLERS
There are several factors to consider, first, when thinking of the importance of dust control. Dust generated during mining activities, such as drilling, blasting, loading and hauling, often contains harmful particles. Prolonged exposure to these dust particles can lead to severe respiratory diseases like silicosis, lung cancer, and other chronic illnesses.
Second, excessive dust reduces visibility, increasing the risk of man-machine interaction and machine-machine interaction. Third, dust can accumulate in and around mining equipment, leading to increased wear and tear of moving parts, leading to costly repairs and downtime.
Finally, dust explosions can occur when high concentrations of combustible dust particles, such as coal dust, come in contact with an ignition source like a spark, hot surface, within a confined space.
Switching gears now to mobile water sprinklers, also known as water jet tankers. It’s important to note that on unpaved haul roads, large loaders, dumpers and trucks travel in and out of mines multiple times a day, generating significant amounts of airborne dust. This dust is primarily managed through the use of water. Mobile water sprinkler systems are manually operated by a trained operator, who navigates the specially designed vehicle equipped with a rear-mounted tanker. The vehicle features a versatile water cannon or a perforated metal bar with precision nozzles, strategically positioned at the rear or front.
Through advanced hydraulic and electrical circuits, the system offers multiple water dispersal modes, including:
- Pressurized sprinkling for broad coverage.
- Water jet for targeted dust suppression.
- Gravity sprinkling for gentle, widespread distribution.
- Mist sprinkling for fine particle control.
The operator assesses the dust levels in real-time and selects the optimal sprinkling mode to effectively mitigate dust in underground mines, ensuring a safer working environment and minimizing environmental impact.
MOBILE FUEL BOWSERS
The smooth and efficient execution of mining operations hinges on a dependable fuel supply. Mobile fuel supply bowsers directly address this concern, contributing to productivity in several key ways.
- Continuous operations. Mobile fuel supply bowsers play a vital role in ensuring uninterrupted operations by providing a reliable and efficient fueling solution. Continuous mining activities require regular fueling of heavy machinery, such as loaders, trucks, dumpers and drills, to prevent costly downtime.
- Remote and challenging terrain. Many mines are situated in remote areas with limited infrastructure. Fuel bowsers provide a flexible fuel supply solution, overcoming challenges posed by geography and accessibility.
- Fuel efficiency and management. By monitoring fuel consumption through integrated meters, bowsers enable precise inventory management, reducing waste and optimizing fuel usage.
- Risk mitigation. In addition to ensuring operational continuity, fuel bowsers play a critical role in emergency preparedness. They serve as a reliable backup fuel source in case of supply chain disruptions.
Underground mining operations involves remote and inaccessible areas within the site. It involves heavy machinery, including loaders, haul trucks, and drills, which require frequent refueling to maintain operational continuity. Fuel bowsers provide a reliable and efficient way to deliver fuel directly to mining equipment, stationed deep within the mine, thus reducing downtime and optimizing productivity by eliminating the need to bring machinery to the surface for refueling.
A fuel bowser, referred to also as a fuel tanker or dispenser, is designed to transport and dispense liquid fuels like gasoline, diesel and kerosene. The main components include a durable fuel tank made of corrosion-resistant materials, a dispensing pump powered by the vehicle’s engine or an electric motor, and a nozzle that controls the fuel flow into the receiving vehicle. A flexible hose connects the nozzle to the pump, allowing easy maneuvering during refueling and an integrated flow meter accurately measures fuel dispensed, aiding billing and inventory management.
Mobile fuel bowsers are often equipped with safety features such as an emergency stop switch to halt fuel flow, an automatic shut-off valve to prevent spillage, a pressure relief valve to release excess pressure, and fire extinguishers (manual and automatic suppression systems) for countering fire.
SCISSOR LIFTS (AERIAL WORK PLATFORMS)
Underground mining operations often demand safe and reliable access to elevated areas. Scissor lifts provide crucial vertical access for various tasks, including:
- Installation work. For tasks like installing ventilation ducts, electrical lines, and piping in mines, scissor lifts are commonly used. Scissor lifts offer a stable platform for work at lower heights, making them ideal for straightforward vertical access. These platforms facilitate safe and efficient installation of various services in mining operations.
- Infrastructure work. Concrete wall construction is a standard practice in underground mining, providing essential reinforcement for safety and stability. These walls serve multiple functions, such as containing hazardous areas, preventing water seepage, and supporting weak rock zones that might otherwise compromise the mine’s structural integrity. Scissor lifts play a vital role in this process by providing workers with safe, stable access to elevated areas, enabling precise placement and application of materials, particularly in tight underground spaces. With scissor lifts, workers can reach greater heights efficiently, facilitating tasks like installing rebar, placing formwork, and applying shotcrete or concrete with accuracy.
In underground mining, scissor lifts are typically equipped with hydraulic systems, using a hydraulic pump to transfer pressurized oil from a reservoir into hydraulic cylinders to raise the platform. These lifts feature a stack of crossed tubes that extend and retract in a scissor-like motion, enabling smooth elevation and lowering. Positioned behind the engine end after articulation, the lift platform provides stable access to elevated areas.
Operators can choose between diesel-powered or fully electric engines, depending on site requirements and environmental considerations. Designed for moderate weight capacity, scissor lifts are user-friendly, with a single operator controlling the machine from multiple control positions. For added stability, hydraulic support legs or jacks secure the lift, making it reliable for diverse mining operations.
EXPLOSIVE TRANSPORT VEHICLES
The handling and transportation of explosives in underground mines is a high-stakes operation and requires meticulous planning and execution. Here are four critical risks to consider:
- Risk of accidental explosion. Explosives are highly sensitive and can go off if they’re exposed to shock, high temperatures, or pressure. Underground mines are tight spaces with few ways out, so if an explosion happens during transport, it could lead to serious injuries, deaths, or trap miners inside.
- Fire risk. Some explosives have materials that can catch fire easily. In underground mines, fires can spread quickly and are very dangerous in closed areas. Safe transport methods help prevent fires from starting and spreading.
- Environmental contamination. Explosives and their waste can harm the environment, like water and soil, if they leak or spill. Safe handling and transportation reduce the chances of this happening, keeping the surrounding ecosystem safe.
- Legal requirements. Most countries have strict laws about moving explosives. Following these rules is necessary to avoid fines and protect the safety of both workers and the public.
An explosive transport vehicle is specially designed to safely carry explosives, particularly in hazardous environments like underground mines. Explosive transport vehicles are designed with multiple safety features to ensure the secure transportation of hazardous materials. These vehicles are equipped with lockable, secure compartments covered in inflammable material to protect explosives from damage and accidental detonation.
Many vehicles also have fire suppression systems to quickly extinguish fires, reducing the risk of spread. Clear markings with hazard symbols and warning signs alert others to the dangerous cargo. Additionally, shock absorption systems minimize the risk of accidental detonation by reducing the impact of shocks and vibrations. Finally, emergency shut-off systems allow for quick vehicle disablement in case of emergencies.
MECHANICAL SCALING EQUIPMENT
Scaling can be described as a specialized technique used to detect, dislodge, and remove loose rock fragments from the walls and ceilings of underground mines following blasting operations. It aims to stabilize the rock face, preventing potential rock falls and ensuring the safety of miners by creating a secure working environment. Scaling can be done by two techniques:
Manual scaling. In this technique, Scaling bars are used to remove rocks off the backs, walls or face. Manual scaling is widely recognized as one of the most hazardous tasks in underground mining. The worker performing scaling operates in close proximity to the rock face, exposing them to potentially unstable ground that could collapse without warning. This proximity to lose, fractured rock significantly increases the risk of injury, as sudden rock falls or shifts can occur unexpectedly. Therefore, manual scaling requires a high level of caution, awareness, and skill to ensure both the safety of the worker and the stability of the surrounding environment.
Mechanized scaling. The inherent dangers associated with manual scaling underscore the need for mechanized scaling techniques. In this process, scaling is typically executed using specialized equipment such as hydraulic scaling hammers or dedicated scaling machines. In mechanized scaling, traditional scaling bars are replaced by large, powerful chisels that are hydraulically operated to penetrate and dislodge loose rock.
With features such as extended reach for safe access to difficult or elevated areas, protective cabins that shield operators from falling debris, and increased productivity by enabling quicker, more consistent coverage of larger areas, mechanized scaling significantly enhances safety, expedites the scaling process, and improves the stability and overall efficiency of mining operations.
EXPLOSIVE CHARGING EQUIPMENT
Charging equipment in underground mining refers to the machinery and tools used to load explosives into drill holes for blasting operations. This process is crucial for breaking rock and creating new mining faces. Generally, two kinds of charging equipment is used in underground mining:
Emulsion Chargers. Emulsion explosives are a type of high-energy explosive that offers superior performance and safety compared to traditional explosives like ANFO. Emulsion chargers are designed to handle and deliver these emulsion explosives into drill holes. They are typically equipped with precise metering systems, high-pressure pumps, and specialized hoses to ensure accurate and efficient loading.
ANFO Chargers. ANFO (Ammonium Nitrate Fuel Oil) is a popular blasting agent due to its cost-effectiveness and ease of use. ANFO chargers are designed to load bulk ANFO into drill holes. They often feature pneumatic or hydraulic systems to convey the ANFO from the bulk storage to the drill hole.
PASSENGER CARRIERS
Passenger carriers play a vital role in underground mining by ensuring the safe and efficient transportation of personnel within the mine. Designed to endure the challenging underground environment – including low visibility, uneven terrain, and various hazards – these vehicles are indispensable tools for mining operations. Commonly referred to as utility vehicles or personnel carriers, they are specifically built to accommodate small groups of miners and serve several key functions, such as:
- Transporting crews to and from work areas. These vehicles facilitate the efficient movement of crews to their designated work locations, often deep within the mine.
- Supporting maintenance operations. Maintenance teams depend on personnel carriers to reach different sections of the mine for repairs, inspections, and troubleshooting tasks.
- Emergency response. In urgent situations, personnel carriers enable rapid deployment of emergency response teams to affected areas.
Personnel carriers used in underground mining are designed with advanced safety features to ensure passenger well-being in challenging environments. Each seat is equipped with individual seat belts to reduce the risk of injury during sudden stops or on rough terrain, while ergonomic cushioned seats enhance comfort and minimize fatigue on long journeys. Hand straps are strategically placed to provide passengers with a secure grip during bumpy rides.
For effective communication, a passenger-operator alarm system allows passengers to signal the operator to stop the vehicle promptly in case of emergencies or operational needs. Cabin lighting ensures adequate visibility inside the carrier, improving safety even in low-light conditions. Additionally, an automatic parking system engages immediately if a door is accidentally opened during operation, preventing unintended movement and mitigating potential risks. These features collectively prioritize passenger safety, comfort and operational reliability in underground mining operations.
FUTURE DEVELOPMENT AND CHALLENGES
The future of utility vehicles in mining is increasingly electric, driven by the need for sustainability, cost efficiency, and safety improvements. Electric UVs offer zero emissions, lower operating costs, and improved safety, making them an attractive alternative to traditional diesel-powered vehicles. Advancements in autonomous technology, IoT integration, and fast-charging infrastructure will further enhance efficiency and operational control.
While electric UVs offer numerous benefits, there are also challenges to consider. One major hurdle is the development of charging infrastructure, which is crucial to support the widespread adoption of electric UVs. Additionally, advances in battery technology are needed to improve range, reduce weight, and lower costs. Furthermore, governments and regulatory bodies must create frameworks to support the adoption of electric UVs, providing clarity and guidance for mining companies looking to make the transition to electric.
About the author: Harshvardhan Singh is a senior service engineer for Zawar Mines in Udaipur, India.