The ultra-heavy-duty machines can lift and carry 50 tons at a distance of 60” from the fork face. DBT said the capacity of the VT650 is unparalleled by any other battery-powered shield hauler on the market.
The MINExpo machine is destined for delivery to Massey Energy Company following the expo. A further three machines have been ordered by Massey for the end of the 2005 first quarter.
DBT said the machine offers quiet, clean performance from two 50 HP dual-field DC motors which develops up to 97,450 lbs of tractive effort.
The new VT650 has a control stick giving simple, intuitive control over steering, tramming direction, pump starts and all other functions of this state-of-the-art hauler. A hydraulically adjustable cab ensures versatility for negotiating varying mining conditions and increased flexibility during transport.
The tri-section frame pioneered in the earlier Long-Airdox VT636-2 machine was maintained for the VT650, but with a 180% increase in the strength of the oscillation bearing. This frame configuration allows the rear frame and attached Ground-Level Battery Changer to rotate independently of the load half of the machine, ensuring the rear wheels maintain contact with the roadway even under severe conditions.
The VT650 battery pack has a capacity of 2000 Ah, allowing over 800 tons to be moved per battery charge. In addition, a new charger has been developed to ensure maximum battery life and a full charge.
DBT has also focused on maintenance ease with the machine, locating the electrical enclosure for the controller on the operator’s side of the intermediate frame. This facilitates maintenance and eliminates the need for heavy power cables to pass through the articulation joint between the front and intermediate frames.
The pump motor and directly mounted pump are located in a compartment accessed from the off side of the intermediate frame, allowing direct access to the pump from the articulation area without the need to remove the large rib protection covers on the side of the machine. The pump/motor assembly sits over a removable 50-gallon hydraulic reservoir. A separate 20-gallon reservoir is mounted in the frame under the controller housing and will be used as a dedicated brake cooling sump.
Easy access to hydraulic components – including the main control valve – has been provided by locating them centrally found in the hydraulic bay opposite the operator on the front frame. Pilot controls have been use to ensure maximum life of the control valve and allow ergonomic placement of controls.
A 75,000 lb capacity winch facilitates loading. The mounting is designed to allow easy removal of the winch assembly and features strap-type retention of the winch feet instead of relying totally on a bolt retention that could loosen over time. A new pin attachment mechanism allows quick and secure replacement of lifting forks in the event of damage.
The axles are heavy-duty, fabricated alloy steel housings with outboard planetaries and wet-disk service/parking brakes in each wheel end. The parking and service brakes are “spring-applied hydraulic-release”. The sturdy wheel and tire combination has been specifically designed for the VT650, with 54” diameter and 26” wide tires.
