Liebherr R 9800
An 800-tonne hydraulic mining excavator built to load the very largest haul trucks in a handful of passes, and one of the two or three largest hydraulic excavators ever put into series production.
Transport height: 10.3 m — about 5.7× an average adult's height (1.8 m). The machine is always drawn at the same size here; the human figure is what actually scales.
01Overview
An 800-tonne hydraulic mining excavator built to load the very largest haul trucks in a handful of passes, and one of the two or three largest hydraulic excavators ever put into series production.
02Purpose
It exists to close the gap between hydraulic excavators and the largest cable shovels — giving mines a hydraulic machine that can still load the biggest haul trucks in a handful of passes, without switching to cable-and-hoist mechanics.
03Historical Development
Liebherr introduced the R 9800 in 2011 to compete directly with cable-operated electric mining shovels on the biggest jobs, betting that hydraulics — by then dominant at every smaller size class — could scale all the way to the top of the market. It has since become a fixture at copper and oil-sands operations that need a shovel able to fill a 400-tonne haul truck in three to five passes.
04Core Components
- UndercarriageTwin-crawler base carrying the full 800-tonne weight and distributing it across the ground at a pressure the pit floor can actually support.
- Slew ring & houseThe turntable bearing and upper structure that let the entire cab, boom, and counterweight rotate independently of the tracks.
- Boom & stick (or dipper handle)The two-piece arm — configurable as a backhoe or a face shovel — that positions the bucket.
- Hydraulic cylindersBoom, stick, and bucket cylinders, some over a metre in bore diameter, that do all the digging force work.
- Twin diesel enginesTwo engines running in parallel, because no single diesel built reaches 4,000 hp in a package this size.
05How It Works
Two diesel engines drive a bank of hydraulic pumps that pressurise oil to roughly 350 bar. Operator inputs open proportional valves that route that pressurised oil to the boom, stick, and bucket cylinders in whatever combination curls the bucket through the bank, exactly like a human arm scaled up a hundredfold. The same hydraulic system also drives the crawler tracks and the slew motor that rotates the whole upper structure to dump each load into a waiting truck.
06Engineering Principles
Every digging motion — boom, stick, and bucket curl — is a hydraulic cylinder converting oil pressure directly into linear force at a scale few other machines approach.
HydraulicsPascal's LawThe whole hydraulic system is Pascal's Law in industrial form: one pressure, generated once, delivered wherever a hose can reach.
MechanicsTorqueThe slew drive that rotates the 800-tonne upper structure needs sustained torque, not speed, to start and stop that mass smoothly.
07Performance Characteristics
| Operating weight | 800 t (backhoe) |
| Bucket capacity | 36 – 42 m³ |
| Engine output | 2 × 2,000 hp |
| Max digging depth | ~9 m |
| Max tear-out force | 1,760 kN |
08Notable Examples
- R 9800 fleet, Chilean copper minesMultiple units run in tandem with Cat 797-class haul trucks at some of the world's largest open-pit copper operations.
- Athabasca oil sands, CanadaR 9800s in face-shovel configuration load oil-sands ore directly into haul trucks ahead of processing.
09Interesting Facts
- Its standard bucket, at up to 42 m³, could comfortably hold a small delivery van.
- The R 9800 can be configured on-site as either a backhoe (digging toward itself) or a face shovel (digging upward and away) by rearranging the same boom components.
- At 800 tonnes, it weighs roughly as much as a fully loaded Airbus A380.