LHD machines are used in underground mines to load and transport ore
and minerals. Loading and hauling blasted ore from draw point to dumping point constitute a
significant portion of the production costs for mining companies. There are a number of
operation modes available for LHDs, and there are many criteria to consider when selecting
the best one.
Uses of Load Haul Dump
One is to improve maintenance, and moving from operator-assisted “fail and fix” to planned maintenance. Since the operator is removed from the
machine during automatic operation and maintenance staff is not always available on short
notice, it is crucial to increase planned maintenance to maximize the investment in
automation. Another issue is the complexity of the mining environment, including both the
infrastructure and external disturbances like over-sized boulders and road maintenance, as
these can throw the entire investment in automation into question.
The working principle and process of LHD machine
The Underground LHD machine can load, transport, and unload. It is self-propelled equipment. The working process of the LHD machine in mining can be reflected on the working device. The length of the lifting cylinder and the rotating bucket cylinder determines the various working conditions of the working device. Its working process consists of 5 working conditions:
- Insertion conditions:
The boom is lowered, the bucket is placed on the ground, the tip of the bucket touches the ground, the bottom of the bucket is at an angle of 3°-50° with the ground, and the bucket is inserted into the pile by the traction of the machine.
- Shovel loading conditions:
After the bucket is inserted into the material pile, turn the bucket to shovel the material until the bucket mouth is turned to approximately level.
- Lifting conditions:
After the bucket is retracted, use the lifting cylinder to rotate the boom to the proper unloading position.
- Unloading conditions:
Use the bucket cylinder to turn the bucket over and unload it to the transport vehicle. Then lower the boom to restore the bucket to the transport position.
- Automatic leveling conditions:
After the bucket is unloaded at the highest lifting position at 45°, keep the length of the bucket cylinder unchanged. When the boom is placed in the digging position, the rear angle between the bottom of the bucket and the ground plane is 300-500.
The Advantages of LHD
1.No exhaust leads to better visibility and better working conditions.2.reduce vibration and heat and provide better working conditions for employees. 3.noise reduction.4.cost saving in ventilation , fuel ,consumables,inspection and maintenance.5.zero emissions.6 underground diesel loader uses high efficiency engine, high power, low pollution.the power transmission adopts hydraulic transmission
The Disadvantages of LHD
The movement between the levels became more
difficult since the cab was removed from the automated LHD and therefore the operator
had no place to sit points out some of the problems
with automatic systems. He claims that some of the issues are that it is rather costly to
install the automatic systems and that the mine needs to meet some specific physical
requirements. This means that it seems like large-scale mining will get more significant
benefits from installing the whole package where production can be increased in large
cycle applications. Ca steel further mentions that the system can be fitted to suit smaller
operations as well though it is easier to install the technology in mine sections that have
planned to use it
According to bucket capacity
Small LHD machine: LHD scoop with a bucket capacity of 1.5m³ and below.
Medium LHD machine: LHD scoop with a bucket capacity of 2-4m³.
Large LHD machine: LHD scoop with a bucket capacity of 4m³ and above.
