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Failure of transmission systems components on Aker 50-15 offshore cranes

Set out below is Safety Notice 2/97 issued by the UK Health and Safety Executive (HSE). It should be self explanatory.

Failure of Transmission Systems Components on Aker 50-15 Offshore Cranes

The Health and Safety Executive has been advised of failures which have occurred in mechanical components of the winch hoist transmission system on Aker 50-15 offshore cranes. This has resulted in the load and boom going into uncontrolled free fall with consequential severe damage occurring to the crane and surrounding structure. There may also be implications for injury to attendant personnel.

Failures have occurred at the following areas:

  1. the hubs of winch drum castings where the drum support bearings are fitted;
  2. the hydraulic motor shaft on which the drum drive pinion is mounted;
  3. the drum drive pinion tail support bearing.

You are advised therefore that if any crane under your control is of the manufacturer indicated, then the boom, main hoist and whip hoist transmission systems should be dismantled and inspected around the regions indicated in Figure 1.

Please be aware that other models of this crane manufacture may be of a slightly different design to that illustrated. However in the interest of safety, dismantling and inspection is also advised in these cases.

Any queries relating to this HSE Safety Notice should be addressed to:
Health and Safety Executive Offshore Safety Division Room 134 Lord Cullen House Fraser Place Aberdeen, UK AB23 3UB
Tel: + 44 (0)1224 252 500

Figure 1: Main, boom and whip hoist transmission system Aker 50-15 cranes
Figure 1: Main, boom and whip hoist transmission system Aker 50-15 cranes

Area A – covered by paragraph 2(i)
Area B – covered by paragraph 2(v)
Area C – covered by paragraph 2(iii)

This guidance is issued by the Health & Safety Executive. Following the guidance is not compulsory and you are free to take other action. But if you do follow the guidance you will normally be doing enough to comply with the law. Health and safety inspectors seek to secure compliance with the law and may refer to this guidance as illustrating good practice.

Safety Event

Published: 1 January 1998
Download: IMCA SF 01/98

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