Safety alert 11/2012 - Weld cracking in transportable pressure discharge dry bulk powder vessels

This publication is for: 
Employee / workerEmployer

Recent inspections of pressurised bulk tankers after twelve months service have found significant internal cracking in welded areas that could propagate into major defects and cause a pressure vessel failure. Areas of concern include shedder plating, discharge piping and internal stiffeners.

Contributing factors

  • Design and fabrication quality of the shedder plating support structures, discharge piping and stiffeners.
  • Standard of workmanship in the welding in the above areas.
  • Local service conditions such as handling, storage and transportation (road conditions and distance travelled).

Action required

  • Engage a competent person to carry out an internal inspection of the vessel if it has not been inspected in the last twelve months.
  • Remove from service any item of plant identified as unsafe, until all defects have been corrected and a competent person has re-inspected the plant.
  • Review in-service inspection intervals based on the results of this inspection.
  • Retain records of inspection, maintenance and repair for each item of plant.

Further information

If your inspections identify any of the issues outlined above then you should contact the designer, manufacturer, importer or local supplier of the plant in relation to appropriate methods for correcting the defects. You can also refer to AS/NZS 3788:2006 – Pressure Equipment In-service Inspection.

Further information can be obtained from WorkSafe’s website or by contacting customer service on 1300 307 877 or email

This Alert contains safety information following inquiries made by WorkSafe about an incident or unsafe practice. The information contained in this Alert does not necessarily include the outcome of WorkSafe’s action with respect to an incident. WorkSafe does not warrant the information in this Alert is complete or up to date and does not accept any liability to any person for the information in this report or as to its use.

Last updated 29 Jun 2017

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