The Gradall XL 3200V Lo Pro crawler excavator is designed specifically for extra-low overhead jobs including “top-down” construction projects, where excavation work must be completed beneath a 10-foot ceiling.
With a bucket attached to its boom-end, the unit has an overall height of just 9 feet 5 inches, which is some 16 inches shorter than the standard 10-foot 9-inch overall height of an XL 3200 V model with a bucket. Extending the bucket below the ground line to dig also requires just 9 feet 5 inches feet of height, compared with the standard 14 feet required by the XL 3200V.
|Engine||Boom force||Bucket breakout force||Reach|
|Volvo Penta T4-F||21,940 lb.||19,240 lb.||27' 6"|
Top-down is a popular deep construction approach in New England to build underground parking garages and underpasses on tight job sites where soil movement must be minimized. Permanent structure floors are built underground as the excavation progresses beneath them. Excavation work and soil removal must be accomplished within the limited space between one underground floor and the one above it, typically providing less than enough space for conventional excavators to work.
The standard telescoping boom on a Gradall excavator is already designed to meet the need to operate productively with limited overhead space. Unlike conventional excavator booms, which require extra overhead space for the knuckle boom to function, the Gradall telescoping boom extends straight out, and then retracts with only a minimal height requirement, the company says.
The full-boom tilting action, 110 degrees in either direction, along with up to 27 feet 6 inches of reach allow the operator to scrape dirt away from the floors and walls on a top-down job, and then move the dirt to a glory hole where it can be extracted with a clamshell bucket.
The XL 3200V LoPro has a rated boom force of 21,940 pounds and bucket breakout force of 19,240 pounds, enabling it to handle high-production excavation and demolition. The high-pressure hydraulics system adjusts automatically to save fuel and eliminate the need for mode selection. The machine is powered by a Tier 4-F-compliant Volvo Penta engine.
All Gradall Series V models also have 24-volt electrical systems, and electronic joysticks, built into the seating module, control all boom tilt, telescoping, swing, and raising/lowering motions. An in-cab switch allows the operator to select the Gradall, Deere, or SAE joystick pattern.
A compact counterweight design shortens the rear swing of the XL 3200V Lo Pro, permitting the machine to swing and move in tight underground spaces. Maneuverability is enhanced with dual-range high-torque piston motors on each of the crawler tracks, Gradall says. Triple grouser excavator pads, with widths of 31 inches or 23 inches, help mobility in mud, sand, and dirt.
For individual crawler speed and direction control, the operator has two electronic foot pedals with handles in the cab. An automatic two-speed control can shift the crawler into low speed for challenging travel conditions. Also, the operator can manually switch from high speed to low speed when loading the machine for transport.
Routine maintenance and adjustments are simplified. For example, track tension is controlled with an adjustment cylinder. A recoil spring on each crawler idler keeps rocks and debris from breaking or jamming the track rail, and sealed rollers feature lifetime lubrication. The carrier frame is a one-piece weldment and the triangular boom protects the boom tilt motor, located at the rear of the boom.