In place of hydraulic motors, electric motors are already being tried in rotary functions. Linear actuators replacing hydraulic cylinders being developed in various sizes suitable for hydraulic excavators are the real game-changers, says M V Rajasekhar, Director (Mining & Construction) BEML...
In place of hydraulic motors, electric motors are already being tried in rotary functions. Linear actuators replacing hydraulic cylinders being developed in various sizes suitable for hydraulic excavators are the real game-changers, says M V Rajasekhar, Director (Mining & Construction) BEML Ltd.
The global mining machinery market size is projected to reach USD 36.2 billion by 2025. What are the latest trends in the mining equipment segment?
The mining equipment segment is undergoing major changes that include the introduction of higher capacity mining equipment to increase production & productivity, additional safety features, environmentally friendly equipment, and the use of the latest technologies for ease of operations.
Some of the latest technologies and emerging trends on Mining Equipment are as follows:
AC drives system for Electric dump trucks which is more reliable and has longer life.
Environment friendly Electric Hydraulic Excavators
Emission norms compliant engines
Operator fatigue monitoring system
Electronic type proximity avoidance system
Auto Dipping System
Zone specific based Auto Fire detection & suppression systems
Modular design-based machinery
AI & Telematics based remote-controlled machinery
Sustainable mining is the buzzword today. Please brief us on your product portfolio that meet sustainability objectives.
BEML is continuously developing and manufacturing mining equipment with the latest technologies for sustainable mining and to reduce carbon print. For eg., BEML equipment is powered by fuel-efficient and emissions norms compliant engines.
Our BE1800E (180 T class) Electric Hydraulic Excavator BH150E, Electric Dump Truck with 136 MT payload, BH205E Electric Dump Truck with 186 MT payload, BE1800D Hydraulic Excavator (180T class) and BD475 Bulldozer (850 HP class) are all environmentally friendly. Recently, BEML signed MoU with CIL and GAIL to introduce dual fuel engine (Diesel & LNG) on 100T dumper initially, which reduce operating cost and carbon print and is under development. BEML鈥檚 latest technology higher capacities mining equipment increases the production and productivity of mines.
BEML Mining & Construction equipment product ranges from:
Rear Dump Trucks: 35T 鈥� 205T
Bulldozers: 90 HP 鈥� 850 HP
Hydraulic Excavators: 7.5T 鈥� 175T
Motor Graders: 125 HP 鈥� 280 HP
Wheel Loaders: 1.7 cum 鈥� 4.7 cum
Water Sprinklers: 28000 Litres & 70000 Litres
Tyre Handler: Tyre Size: 18x25 鈥� 36x51; Tyre Lift: 3500 kg
Globally, many companies have started using electric-driven machinery. How is the demand in India? What advantages do they offer over traditional equipment?
Yes, higher capacity electrically driven loading equipment are generally adopted in large and high production opencast coal mines, where mobility of the equipment is less. These equipment are Electric Hydraulic Excavators, Electric Rope Shovels, and Walking Draglines.
Moreover, electric-driven machines have the following advantages over diesel-driven machines due to their higher reliability & availability and being environment friendly (zero-emission & less noise pollution). These add to its long life of sub-assemblies like motor compared to mechanical sub-assemblies like Engine, Transmission, and Final Drive.
Also, it consumes less power, is simpler in design with ease of maintenance thereby low on cost and time.
Diesel machinery generates dangerous fumes that are harmful to operators. Hence, according to industry experts, underground mining machinery electrification is more likely to take place compared to surface mining machinery. Please share your views.
We have to take into consideration that around 95% of total coal production in India is from open-cast mining projects. Most of the equipment used in underground coal mines are electrically powered - SDL, LHD, Continuous Miner, and Longwall Mining Equipment. Also, battery-operated mine locomotives are working in some underground coal mines.
On the other hand, diesel-powered underground mining equipment has limitations of usage due to exhaust gases emission. Hence, electrically driven equipment are predominately used in underground coal mines.
However, even in surface mining, electrically powered loading equipment - Electric Hydraulic Excavators, Rope Shovels, and Draglines are generally deployed in large and higher capacity mining projects. But please note that electrically driven dump trucks are yet to be adopted in Indian opencast mines due to mobility constraints.
Technology plays a vital role in equipment design and making. What are the latest technology and design trends?
Here we list the technology trends in various categories equipment-wise as listed below:
Excavators:
Electrical driven excavators in higher weight categories 鈥� 100T and above class
Equipment health monitoring system
Autonomous operation
Bulldozers & Wheel Loaders:
Hydrostatic Transmission
The technology trends are given for equipment categories.
EXCAVATORS
Electrical Drive: The electrical motor-driven excavators are well established in the higher weight categories like 100ton and above class. The electric power to the motor is through a cable with 6.6 kV line. This design and engineering ensure compact aggregates in power to weight ratio and the hydraulic excavators in mining work are used less for travel (maybe 5~6 % of overall time). Hence having a trailing cable is the best design and typically ROI is in the range of 3~4 years of time.
The smaller capacity excavators fall in the category of construction equipment class and are frequently on the move from one workplace to another, so the trailing cable design is not suitable.
The evolution of compact high-power batteries of the Lithium-Ion range offers an excellent source of power to electrify the construction excavators. A typical working duration of 4~6 hours of operation with 1~2 hours of charging ensure 2 ~3 shift operation of the electric drive excavator in a day.
Equipment health monitoring: The GPS tracks the machine for its physical location, nature of work, and equipment health parameters, which helps in planning the maintenance schedule. The new algorithms are predicting the life of the aggregate considering the current health of the aggregates and the maintenance practice followed. This will give further data to the maintenance team to plan for the spares procurement which in turn reduces the downtime and increases the productivity of the machines. The predictive health monitoring requires a lot of past data of the machine and the maintenance practice followed, this is being implemented by many leading OEMs.
High operating pressure: The equipment is designed with high operating pressure to further improve the power to weight ratio of the hydraulic aggregates and systems. The reduction in sizes reduces the hydraulic oil consumption during replacement.
Autonomous operation: The remote line of sight operation, remote operation of multiple types of equipment sitting in the control room away from the harsh and dangerous working environment are being implemented by many OEMs in many mines. The next stage is a complete autonomous operation based on the live inputs from Drones, LIDARs, Lasers, various angles, distance, pressure sensors. The data is processed in the controllers mounted on the equipment and complete operation is carried out without the involvement/interference of humans. This technology is being tried on Dumpers by various OEMs, however, on excavators, it is still in the trial stage. Once this gets proved it will improve the productivity and overall efficiency of the mining operation.
Power cells: As an alternate fuel, power cells are being experimented with, still is in the development stage.
Electric Actuators: In place of Hydraulic motors, electric motors are already being tried in rotary functions. Linear actuators replacing hydraulic cylinders being developed in various sizes suitable for hydraulic excavators are the real game-changers, which will completely eliminate the hydraulic oil from the excavator other than for the lubrication purpose. This is being tried on small excavators by a few leading OEMs.
ROPE SHOVELS:
Hybrid Drive: The wire rope with winch electrical systems is being replaced with hydraulic cylinders for precise and positive control of the operations which improves productivity. In some applications where high voltage electricity is not available, some OEMs are developing Diesel Engine driven prime movers in place of Electric motor driven. All the electric systems are converted to AC in place of DC system.
DOZERS AND PIPE LAYERS:
Hybrid Drive: Engine-coupled generator systems are being developed by some OEMs and being used in regular production. This will improve the life of the power line aggregates as there will be very few rotating parts (Transmission will be deleted) and ensuring smooth control.
Hydrostatic transmission: HST is getting popular and being increasingly accepted by customers. Moreover, ensuring its availability and development of the new aggregates, in turn, ease the dependency on the few sources. This system in place of conventional power line aggregates like the torque converter, the transmission reduces the number of aggregates and improves the operator controllability and efficiency.
The servicing improves, as the hydraulic aggregates are very compact with a very high power to weight ratio and are normally mounted remotely independent of other aggregates, which reduces the service time, and improves the availability of the equipment.
Hydraulic cylinders in place of a hydraulic winch in pipe layers: Many OEMs are already switched to a hydraulic cylinder for the operation of Boom in place of a hydraulic winch, which gives precise control of the boom operation and removes many other safety concerns attached to the winch operation.
WHEELED LOADERS:
Hybrid Drive: Engine coupled Generator systems are being developed by some OEMs and being used in regular production. This will improve the life of the power line aggregates as there will be very less rotating parts (Transmission will be deleted). Smooth control is possible.
Hydrostatic transmission: As explained above HST is increasingly being accepted by the customers with that the availability and development of the new aggregates which in turn eases the dependency on the few sources.
