Grinding using a cutting disc

What happened?

Seamen were grinding sea-fastening spots in the hold, and one of them made a complaint to the Chief Officer about the quality of the grinding discs, they could only grind one spot away before the disc disintegrated and pieces were flying everywhere. The Chief Officer ordered them not to use these discs anymore pending investigation.

What went wrong?

• Investigation revealed that the marking and appearance of the disc led to misunderstanding as to proper use:
  • the discs looked like a normal grinding disc, but also bore the text ‘cutting’, leading to the conclusion that they were cutting discs
  • none of the officers or crew on board had ever seen a cutting disc this thick before, so that is probably why the mistake was made
  • the discs were clearly marked ‘Not to be used for grinding’;
• Further investigation showed from this particular brand (Kronenflex) there is type A24Extra as both a grinding disc and as a cutting disc.

What were the causes?

• There was no check of the disks on delivery, or before use;
  • inadequate attention and awareness of the crew, failing to spot the wrong kind of disc before use.
  • supplier asked to deliver grinding discs and instead delivered cutting discs – but no-one noticed.

What actions were taken? What lessons were learned?

• Ensure crew are thoroughly aware of what happened; a safety moment was planned to show this disc and to demonstrate that it is not a grinding disc, although it looks like one;
• Ensure equipment and tools are carefully selected and inspected before use;
• When ordering these items, the purchase department should ensure the grinding wheels are of good quality and marked with an expiry date.

Members may wish to look at the following:

• Poor storage leading to failure and disintegration of cutting discs
• Grinding disc with defects
• Fatality: grinder incident