Dropped object – Failure of split head elbow on bolts

  • Safety Flash
  • Published on 13 September 2016
  • Generated on 24 July 2026
  • IMCA SF 23/16
  • 1 minute read

A Member has reported two failures of bolts on the split head elbow resulting in two dropped object incidents this year and similar incidents in recent years.

What happened?

During pipelay operations, the split head elbow is assembled around the pipeline pawn head for attachment of the product (pipe) to the storage reel. The elbow is a two-part socket bolted equipment that is fitted by the construction crew on deck before being pulled in to the reel insert and secured.

These bolts have failed on a number of occasions during spooling or laying operations resulting in dropped objects. One contributing factor being considered is the suitability of these bolts for the activity.

Diagram
Diagram

Our member considered the following actions:

  • Use of a brand new set of bolts for each spooling operation.
  • Careful checks to be made to ascertain that all bolts are new and inspected for defects before each assembly operation.
  • Further close attention to be paid to the engineering details of the bolts and the torque settings of the split head elbow.

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