SR Drive systems for new wheel loader and dozer
Switched reluctance technology is providing the all-wheel electric drive for a new range of wheel loaders and dozers for the opencast mining industry.
LeTourneau, manufacturers of the world’s largest wheel loaders, have recently introduced the Pit Bull range of loaders and dozers, which are propelled by SR Drive systems manufactured by LeTourneau, under licence from Harrogate-based SR Drives Ltd.
Designed for loading dumptrucks up to 136 tonnes in arduous mining operations, the Pit Bull L-950 wheel loader has a 13.8m3 bucket that carries a payload of 24.5 tonnes, while the Pit Bull D-950 bulldozer has a 26.75m3 rock blade.
LeTourneau are utilizing the 300kW motor from the SR Drive system that was successfully trialled for over three years on a 180-tonne L-1350 diesel electric loader and is now fitted as standard on these machines. The SR motor dispenses with the shifting of gears and provides extremely high tractive effort, with the rapid torque response minimizing wheel-slip and yielding extended tyre life and reduced operating costs.
The SR Drive system delivers a virtually flat torque/speed curve, providing consistent power at all operating speeds. This, combined with a speed range that is wider than a conventional DC traction motor, translates into faster response to operator inputs, allowing operators to save valuable seconds on every pass and load more material per shift.
The maintenance benefits of the SR motor stem from its simple design. It has no brushes to chip, burn, or be monitored or replaced; no commutator to grind or undercut; and a rotor LeTourneau engineers say is ‘virtually indestructible’. Routine maintenance intervals have increased from around 200h, when the commutator would be inspected, to 20,000h when bearings are replaced. The SR motor’s compact size — about two-thirds that of a comparably rated DC motor — also enhances serviceability through increased access to nearby components.
For further information contact Steve Cummins at SR Drives Ltd on tel: (01423) 845200.
LeTourneau, manufacturers of the world’s largest wheel loaders, have recently introduced the Pit Bull range of loaders and dozers, which are propelled by SR Drive systems manufactured by LeTourneau, under licence from Harrogate-based SR Drives Ltd.
Designed for loading dumptrucks up to 136 tonnes in arduous mining operations, the Pit Bull L-950 wheel loader has a 13.8m3 bucket that carries a payload of 24.5 tonnes, while the Pit Bull D-950 bulldozer has a 26.75m3 rock blade.
LeTourneau are utilizing the 300kW motor from the SR Drive system that was successfully trialled for over three years on a 180-tonne L-1350 diesel electric loader and is now fitted as standard on these machines. The SR motor dispenses with the shifting of gears and provides extremely high tractive effort, with the rapid torque response minimizing wheel-slip and yielding extended tyre life and reduced operating costs.
The SR Drive system delivers a virtually flat torque/speed curve, providing consistent power at all operating speeds. This, combined with a speed range that is wider than a conventional DC traction motor, translates into faster response to operator inputs, allowing operators to save valuable seconds on every pass and load more material per shift.
The maintenance benefits of the SR motor stem from its simple design. It has no brushes to chip, burn, or be monitored or replaced; no commutator to grind or undercut; and a rotor LeTourneau engineers say is ‘virtually indestructible’. Routine maintenance intervals have increased from around 200h, when the commutator would be inspected, to 20,000h when bearings are replaced. The SR motor’s compact size — about two-thirds that of a comparably rated DC motor — also enhances serviceability through increased access to nearby components.
For further information contact Steve Cummins at SR Drives Ltd on tel: (01423) 845200.
