The Worlds Biggest Machines

Introduction | Biggest Engine | Biggest Aeroplane | Biggest Cargo Ship |
| Biggest Truck | Biggest Mobile Crane |
| Tunnel Boring Machine | Rolling Mill | Part Eight |
| Part Nine | Part Ten |

Evidence exists that suggests cranes have been used since the 2nd Century for lifting heavy loads. Unlike their ancient counterparts modern day cranes are designed application specific, resulting in many unique variations and styles, all suited to different lifting tasks in diverse environments. Many cranes are built and work 'in-situ', some permanently such as at dock-sides or shipyards, others temporarily such as at building sites or large construction projects. These are fixed position cranes and remain firmly rooted to the spot on which they were built. Most of the world's tallest and most powerful cranes are of this type.

In some cases mobile cranes are required, often because of the nature and layout of the worksite. These have traditionally been smaller, less powerful, cranes because of physical and mechanical constraints, but innovation in recent years has allowed all that to change.

Mammoet Momo

'Momo', as she is affectionately known, is the largest mobile platform twin-ring containerised (PTC) crane in the world. She was built by Huisman-Itrec for fellow Dutch company Van Seumeren Holland B.V. who trade as Mammoet. Mammoet, meaning mammoth, are a specialist heavy lifting company supplying services across the globe to construction, marine and petrochemical organisations.

PTC cranes are the new generation of specialised lifting gear. Originally, twin-ring cranes were transported to site via custom-built transport and then assembled at the worksite. This led to great expense and required dedicated transport teams to move the cranes. Worldwide operations were particularly difficult and required many months of forward planning. This new generation are designed to break down into individual component parts that can be shipped via standard 40' containers. Momo requires 88 of them. Certain sections of the crane emulate the container shape and size and lock into place directly onto the back of container lorries. The rest of the components are packed into standard containers. This means that shipping can be handled by any containerised-freight company with only an assembly crew needed at the destination.

One could be forgiven for thinking that a crane transported in containers and then assembled at its destination doesn't sound very mobile. It's only when this behemoth is assembled that it can then move under its own power. A skilled crew can assemble the crane in less than a day.

The Twin Ring System

Cranes rotate on a platform known as a 'slewing' ring. The ring is simply a giant bearing designed to hold the weight of the crane while allowing it to rotate. Most mobile cranes, be they tracked or wheeled, have a 'bed' that can be moved to the required site location. Between the bed and the crane body itself lies the slewing ring. The limitation of mobile crane lifting capacity has often been the maximum 'footprint' of the crane bed that can be achieved by using 'outriggers'. Outriggers provide stability to the bed when it is stationery and look rather like large extending feet that effectively increase the surface area of the bed. With the twin-ring design, another giant ring acts as a circular outrigger allowing the crane to rotate not only on its slewing ring, but also on the outrigger itself. Four bogies, housing 54 wheels, interface between the crane body and the steel ring. This provides a much wider footprint and permits much greater lifts.

Ballast is used on the crane to counteract the load. Depending on the load weight, the boom angle and radius of the lift, a 'balancing' amount of ballast is applied by winching into, or away from, the crane centre. This ballast is normally carried within the 'ring' thus allowing the crane to rotate with a load, but for the biggest lifts it can be placed outside the ring providing a greater counterbalancing effect. To the untrained eye it appears that the ballast is fixed during 'superlift' operations and that the crane could only be used for static (rather than rotational) lifts. However, this is not the case. The ballast actually 'floats' a few centimetres above the ground and rotates at the same rate as the crane body.

In order to move the crane, 24 hydraulic rams that connect between the outer ring and the footplates are lifted. The crane bed crawler tracks can then be operated via remote control allowing the crane to be positioned. Progress is slow at 1.5m per minute but the massive machine, complete with stabilising ring, can move as one and prove its mobile ability.

Vital Statistics

Construction of a machine this size consumes a vast amount of raw material. In addition to almost seven kilometres of wire rope, the crane comprises 2,100 metres of electrical wiring, 1,280 meters of hydraulic hosing and 7,000 litres of hydraulic fluids. The bright red finish alone swallowed over 6,000 litres of paint.

• Maximum Load Moment: 33,705 Tonnes
• Maximum Lifting Capacity: 1600 Tonnes
• Crane Weight: 2,100 Tonnes
• Ballast Weight: 1500 Tonnes
• Ring Diameter: 21.5m
• Maximum Radius: 163m
• Main Boom: 49.4 - 97.3m
• Jib: 27.5 - 87.2M
• Height (Including Jib): 185m
• Rotational Speed: 1°/s (360° 6 mins).
• Rotational Drive: 17 hydraulic pumps powering 29 hydraulic motors that drive 29 planetary gears.
• Winch Speed: 80m/minute

Closest Competitors

The Gotwald AK 1200, also owned by Mammoet, is a formidable competitor in the mobile stakes with a maximum capacity of 1200 tonnes. Unlike Momo it is not a twin-ring design; instead it utilises four giant outriggers in a cross formation to provide stability.