World’s largest Cutter Dredger benefits from Radial Fit Bolts

Pilgrim Admin


In 2003 IHC of Holland built, the then world’s largest cutter suction dredger; the J.F.J. De Nul. Which was 142 metres in length and with a massive 35 meter dredging depth, up 16% from the previous largest dredger.

Creating such a vessel was a huge engineering feet with many challenges such as how to handle the abrasive and salt laden environment and massive shock load experienced during cutting operations. Using “conventional bolts” on the cutter shaft in similar applications resulted in seized bolts meaning lost time and damage when removal was required. This would also necessitate machining of the bolt holes and supply of new bolts. In some instances the bolts growing from 76mm Ø to 85mm Ø, this coupled with the significant reduction of the flange diameter due to corrosion damage resulting in costly and time consuming repairs. IHC wanted improvements to remove these issues on the 0.65 metre Ø cutter shaft with its five individual flanges.


PILGRIM designed and provided their Radial Fit Bolts to this application maintaining shaft alignment and prevention of slippage when in-situ. More importantly providing easy removal when required and without causing damage to either the bolt, sleeves or bolt holes, saving time and expense while removing uncertainty by offering predictability to the whole operation of maintenance.


  • Easy to install and remove
  • Removing uncertainty by offering predictability.
  • Lower “Total Life” cost.
  • Eradication of Stuck Bolts and associated damage.