At a special media event in San Antonio, Texas, Vermeer elaborated on precision surface excavation. The process utilizes the Vermeer Terrain Leveler surface excavation machine (SEM), which was created when Vermeer took a rock trencher, removed the trencher attachment and added a patented tilt-head milling attachment with top-down cutting action.
Top-down cutting allows the cutter teeth to gain penetration without using the machine’s tractive effort to drive the teeth into the minerals. As the unit travels forward and the drum rotates, the teeth on top of the drum advance over the top of the mineral surface. As the teeth come down toward the mineral surface, they make contact by impacting the mineral.
A patented drum tilt system allows the operator to control grade in both the lateral and longitudinal directions. The unit can dig up to 21 in. (53.3 cm) deep and 144 in. (365.8 cm) wide in a single pass.
Operators can also control material sizing. Increased tooth penetration increases the material size and decreased tooth penetration reduces the material size. Producing small-sized material in a uniform configuration allows minerals to be handled more efficiently than product produced by drilling and blasting. The uniform product size also allows more efficient settings on secondary and tertiary crushing systems.
Precision surface excavation produces a smooth floor that can minimize wear and tear on mine trucks and loaders, especially on machines with rubber tires. This can also allow the use of off-road trucks in place of mine trucks in many cases.
This technology is ideal for use in a quarry application, especially those faced with drill and blast restrictions or urban encroachment. The advantages of the Vermeer technology are numerous:
- Access areas in surface mines where drilling and blasting cannot either be done because of physical or permitting limitations.
- Low in noise, dust and vibration compared to drill and blast.
- Produce a smaller, more consistent particle size.
- Can take steps and equipment out of the mining process, such as the elimination of a primary crusher.
- Complements drill and blast and don’t necessarily need to replace that method.
- Can be used for site preparation and haul road construction and maintenance.
The Vermeer T1255III Terrain Leveler SEM features:
Single-Sided, Direct Drive Drum. A fully hydrostatic motor mounted to the side of the cutting head provides direct drive power to the cutting drum. This design delivers more horsepower to the cutting drum compared to chain drive systems, resulting in enhanced efficiency. In addition, the drum allows the quarry operator to cut an 80-degree high wall providing slope stability that is desired in high-wall mining applications.
Load Control. This feature allows the machine to automatically adjust the ground speed to use full engine horsepower, which can make the machine more productive, especially when working in varying conditions. The technology provides visual cues to the operator for recommended control adjustment to maximize the machine efforts. The mine owner can monitor how productive the machine is and how it’s being utilized, driving to a more productive jobsite.
Grade Control. Vermeer uses GPS technology – the machine is equipped for plug-and-play use with Trimble GPS technology – to control cutting head depth and pitch. This feature can allow the operator to cut to the mine plan – produce a flat, almost road smooth, surface, cut to grade for drainage or produce a sloped haul road. The technology also eliminates rapid changes in cutting depth, which can impact productivity and provide precision that an operator-controlled system cannot provide.
Steering Control. GPS technology can also be used to create a mine-by-line plan. The quarry would conduct a GPS survey with the mine plan, upload the plan to the GPS system and the machine then automatically cuts to the plan. Machine steering is controlled by the GPS technology, helping remove human error for cutting head overlap, to maximize efficiency of the machine. The GPS system provides an overlap cutting of only 6 in., helping to maximize productivity with each pass. The mine operator can also set parameters to where the machine can and cannot cut.
Dust Suppression System. Two large vacuums pull dust from the enclosed cutting head into baghouses. The collected dust is dropped beneath the machine, helping reduce dust entering the air and the need to source water used to control dust during the mining process.
SmartTEC Performance Software. Assists operators with adjustments to machine controls that help maximize machine performance. This shows the operator the status of the most critical elements of machine performance, with prompts providing visual cues to the operator for recommended control adjustment. Software also monitors and records machine performance for future analysis by the machine owner or fleet manager.
Operator Safety. Features a pressurized cab with filtered air system and air-ride suspension seats for an operator and trainer. Rollover protective module (ROPM) and a falling object protective structure (FOPS) for working near a high pit wall are built into the operator’s cab.
Vermeer Corp., www.vermeer.com