auxanoauxano technologies - improving efficiency and creating a safer enviroment
Hydraulic Bolts


ship owners



ship owner




about auxano technologies - suppliers of hydraulic bolts

Saving time and money when a vessel is not in operation is vital to ship owners and operators;

  • Regardless of that work being scheduled or not
  • Regardless of where in the world the yard is
  • Regardless of what type of vessel it is

Acceptance of conventional fitted bolts along the main propulsion shaft creates serious time and cost implications.

The cost of conventional fitted bolts.
  • Adds unpredictability to the yards maintenance schedule.
  • Increases the length of time taken to split and remove the propulsion shaft.
  • Damages the hole and the bolt on removal.
  • Holes need re‐machining.
  • New class approved bolts required.

To achieve the necessary interference fit between bolt and hole, conventional fitted bolts are machined to a size slightly larger than the hole. Then and sometimes with the use of ‘dry ice’ (or liquid nitrogen), the bolts are forced into the hole using sledgehammers and brute force. Whilst this method complies with all classification rules, it does not take into account the problem of their removal at some point in the future. That is the owner/operator’s problem!

Due to the interference fit, the bolts cannot be removed easily. Removal time is unpredictable and therefore impossible to accurately schedule into a maintenance programme. Removal will almost certainly damage the bolt and also the hole. Opting for hydraulic bolts such as Easi‐Fit / Flexi‐Bolt will eliminate that problem.

So in addition to the repair yard not being able to provide an accurate time schedule for shaft removal, they are likely to need to re‐machine the holes when re‐alignment takes place. Remachining the holes means that new bolts are required. All of which takes time and adds cost to the maintenance programme. Costs that are paid for by the owner/operator.

Benefits of hydraulic bolt
  • Quick and easy to remove.
  • Accurate scheduling of ship yard time during shaft removal.
  • No damage to holes in the shaft.
  • No need for re‐machining of holes.
  • When removing an Easi‐Fit / Flexi‐Bolt, there is no damage to the bolts.
  • The Auxano Easi‐Fit / Flexi‐Bolt is re‐usable.
  • Installation is quick and easy.
  • Where new sections of shaft are required, hydraulic bolts are also re‐usable.
  • Fewer numbers of holes/bolts required when Easi‐Fit / Flexi‐Bolt is considered at the design. stage.