Levingston Offshore Jacking Systems

Levingston has developed the most advanced high speed, high capacity liftboat Jacking System for self-elevating, mobile offshore vessels

After years of proven operational experience and industry demands, Levingston has developed the most advanced high speed, high capacity liftboat Jacking System for the self-elevating, mobile offshore vessel industry. The ABS approved 430 Electro-Hydraulic Jacking System (EHJD-GB430) is designed specifically for the new era of self-elevating, mobile offshore vessels used in the offshore oil and gas industry, wind farm industry and other worldwide offshore markets.

  • Capacity per pinion – 430KIPS per pinion with storm holding of 900KIPS
  • Faster – Jacking at speeds of up to 3.6 mpm (12 fpm)
  • Industry specific design – high operational cycle design consideration for frequent rig moves

The offshore industry demands more from the vessel: more jacking capacity, more speed, and more operational life. The EHJD-GB430 satisfies these demands where no other can, by merging the proven features of the 12 tooth pinion/gearbox design and electro-hydraulic drives. Coupled with "Rolling Chock" technology, the system is the state-of-the-art.

For example on the Levingston 400LE, the jacking system consist of (36) jacking pinions and (18) Rolling Chocks® (which provide additional storm holding brake capacity). The configuration is four jacking pinions and two Rolling Chocks® per chord.

Key features for liftboats and self-elevating vessels:

12 tooth pinions (others use 7 or 9 tooth pinions)

  • Smooth operation – tooth engagement and transition is smoother than alternatives
  • Load sharing – the load is shared between 2 teeth per pinion, thus, higher tooth-to-rack contact

Longer, hollow pinion shafts (others use solid designs)

  • Flexibility – this proven design allows the pinion to rotate slightly under heavy loads

Hydraulic drive (others use alternative hydraulic or electrical motors)

  • High power density motors – permits speed changes and fewer pinions
  • Low inertia – they can respond to sudden reversals with less effect on the drive
  • Speed can be gently varied from a creep to full speed or any intermediate speed
  • Accurate leg loads
  • Jacking System monitoring
  • Network extends to numerous countries worldwide

High Speed Jacking System

Jacking speeds up to 3.6 mpm (12 fpm)

  • High power motors make it possible to reach these speeds
  • 12 tooth pinion smooth operation is crucial to exploiting these higher speeds

Operating capabilities are expanded

  • Mobilizations are faster – operations can be performed in shorter windows
  • High mobility is more tolerant of changing operational considerations

Instant pinion re-torquing with the EHJD-GB430 Jacking System

  • Electro-hydraulic drives automatically load pinions equally when suspended
  • Re-torquing involves the starting the drive, releasing and setting the brakes, and stopping the drive


The effect of seafloor impact on the drivetrain is reduced

  • Pinion shaft flexibility allows give, reducing the maximum load
  • Low inertia stops / reverses easily, reducing the maximum load
  • Faster jacking reduces the number of seabed impacts while lowering legs

Load sharing reduces the loads on all components

  • 12 tooth pinions share loads equally over two teeth
  • Electro-hydraulic drives share loads equally among all pinions

Gentle starts and stops attenuate loads

  • Electro-hydraulics provide smooth changes and fine speed control

Greater tolerance of marine conditions
Oil filled, sealed marine duty brakes resist corrosion and seizing
Electrical power stops at the power unit
Standard electric motors and components are used

  • No VFD interference – no special equipment needed


Jacking 195 metric ton (430 kip)
Holding 295 metric ton (650 kip)
Storm holding 409 metric ton (900 kip)
Travel – full barge load 0 to 1.2 mpm (4 fpm)
Travel – light barge load 0 to 1.8 mpm (6 fpm)
Travel – leg running under no load 0 to 3.6 mpm (12 fpm)
Operating temperature -10 to + 45 C
Reduction ratio 82.5:1


Length 2.6 m (102”)
Diameter (max) 1.32 m (52”)
Weight (approx) 8,181 kg (18,000 lbs)