Sarens SGC-250 “Big Carl”
A purpose-built ring crane with a 5,000-tonne maximum lifting capacity, currently the largest land-based crane in the world.
Max height with jib extended (a working reach, not a parked height): 250.0 m — about 139× 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
A purpose-built ring crane with a 5,000-tonne maximum lifting capacity, currently the largest land-based crane in the world.
02Purpose
Exists for the single mega-lift that would otherwise take weeks of piecemeal crane work — built specifically for projects like Hinkley Point C's prefabricated reactor modules.
03Historical Development
Sarens developed the SGC-250 (Sarens Giant Crane, 250,000 tonne-metre capacity) specifically for a handful of megaprojects too large for any existing mobile or crawler crane, most prominently the Hinkley Point C nuclear power station in the UK, where it lifts entire prefabricated reactor-building modules in single picks that would otherwise require weeks of piecemeal assembly.
04Core Components
- Ring beamA large-diameter ring the crane's upper structure rotates on and derives its stability from, rather than a conventional crawler undercarriage.
- Main boomA lattice boom up to 160 metres long, supplemented by an additional 100-metre heavy-duty jib for extreme-reach lifts.
- Counterweight systemEnormous, precisely positioned counterweight blocks that balance the load moment at the boom's far end.
- Modular transport sectionsEvery major component ships and assembles in sections, because the assembled crane itself is far too large to move as one unit.
05How It Works
Rather than resting the whole crane on crawler tracks the way conventional crawler cranes do, the SGC-250's upper structure rotates on a large ground-level ring, spreading the enormous combined weight of crane and load across a wider footprint than crawlers alone could manage. Hoist winches raise the load via wire rope run through the boom's rigging exactly as on any crane, just at a scale where a single lift can be an entire preassembled building module rather than a beam or a machine part.
06Engineering Principles
Its hoist system is wire-rope mechanical advantage taken to an extreme, multiple rope falls sharing a 5,000-tonne load across the rigging.
MechanicsTorqueSlewing an assembly this size — crane and load together — demands sustained, carefully controlled torque to start and stop rotation without inducing dangerous load swing.
HydraulicsHydraulic CylindersBoom angle and jib adjustments are made through large hydraulic cylinders, even though the primary hoisting force comes from wire rope rather than hydraulics.
07Performance Characteristics
| Max lifting capacity | 5,000 t (at 40 m radius) |
| Load moment | 250,000 t·m |
| Capacity at 100 m radius | 2,000 t |
| Max boom length | 160 m |
| Max height | 250 m |
08Notable Examples
- Hinkley Point C, United KingdomBig Carl lifts entire prefabricated nuclear reactor building modules, some individually weighing over 700 tonnes, directly into position.
09Interesting Facts
- It's nicknamed "Big Carl" after a Sarens project manager, not for any technical reason.
- At full height with its jib extended, it can lift loads roughly 250 metres in the air — taller than most skyscrapers.
- Because its footprint is so large, the crane effectively becomes part of a project's civil-engineering plan: the ground beneath its ring often has to be specially prepared to bear the load.