Mines safety alert no. Newflash | 02 September 2019 | Version 1

Structural failure: Overburden Drill Mast

What happened?

A steel plate 3.3m long x 0.50m wide x 3 mm, weighing approximately 50kg, was positioned on a drill mast to retain the hose travel guides. The plate has detached and fallen approximately 5m off the drill mast striking blast peg basket before landing on the drill bench below.

Recommendations

All mines should immediately audit all modified mobile plant structures to determine the integrity of structures and fixings, the audit should consider:

• the site Modification to Plant SOP
• introduction of plant process for site
• if the structure is fit for purpose
• cracking in stress zones
• cracking of welds and parent metals
• condition of welds
• condition of fasteners
• security of fasteners
• site pre start records for mobile plant

In particular mines should review their maintenance strategies for structures and equipment to:

• confirm that suitable structural inspections are in place
• confirm that the structural inspection is relevant and applicable to the potential failure modes
• confirm that the frequency of the structural inspections is adequate to identify potential failures before they become actual failures

OEMs should be consulted to ensure that correct inspections are used for the aforementioned.

References and further information

Safety Newsflashes Purpose

1. Draw attention to the occurrence of a serious incident(s) in the mining industry
2. Increase Risk awareness
3. Promote mines to examine and check that their controls are adequate

The investigations are ongoing and further information may be published as it becomes available.

The information contained in this publication is based on knowledge and understanding at the time of writing