Grinding stone incident
- Safety Flash
- Published on 1 July 2001
- Generated on 21 December 2025
- IMCA SF 07/01
- 1 minute read
We have received information of an incident involving a cup grinding stone.
What happened?
In this incident, the cup stone exploded. However, the findings are considered applicable to any type of abrasive wheel.
In the incident, a pipe welder was using a pneumatic grinder to bevel the end of a 3″ pipe when the grinding stone exploded, striking the welder on his shoulder.
The investigation revealed that the guard used on the grind was not the correct one for a cup stone and that the flange was not the correct size for the stone.
The following common errors were identified in the use of grinding stones:
- Use of flanges of uneven or too small diameter.
- Use of washers instead of flanges.
- Flanges without proper clearance or relief.
- Excessive tightening, causing flanges to bend.
- Failure to clean all dirt and foreign material from sides of wheels and flanges.
- Forcing a wheel onto an arbour where fit is tight.
- Use of any loose washers or bushings to try to make a wheel fit a machine for which it is not intended.
- Failure to use blotters on wheels.
IMCA Safety Flashes summarise key safety matters and incidents, allowing lessons to be more easily learnt for the benefit of the entire offshore industry.
The effectiveness of the IMCA Safety Flash system depends on the industry sharing information and so avoiding repeat incidents. Incidents are classified according to IOGP's Life Saving Rules.
All information is anonymised or sanitised, as appropriate, and warnings for graphic content included where possible.
IMCA makes every effort to ensure both the accuracy and reliability of the information shared, but is not be liable for any guidance and/or recommendation and/or statement herein contained.
The information contained in this document does not fulfil or replace any individual's or Member's legal, regulatory or other duties or obligations in respect of their operations. Individuals and Members remain solely responsible for the safe, lawful and proper conduct of their operations.
Share your safety incidents with IMCA online. Sign-up to receive Safety Flashes straight to your email.