An investigation found that a pump cart was also significantly damaged due to the rupture of the high-pressure emulsion line after the longwall mine lost electrical and hydraulic power on the face.
No personnel were working in the area at the time and no one was injured as a result.
A Queensland government safety alert attributed the over-pressurisation to hosing rubbing together and compromising the integrity of the outer casing and steel reinforcing braids.
Poor design, including hose routing, hose retention and hose segregation, were major contributing factors to the incident, according to the Mines Inspectorate’s report.
“No inspection regime was in place for the hoses and other components. In this instance, a personnel walkway was directly above the site of the hose failure and the section of walkway was ejected,” the report stated.
“Fortunately no one was in the area or on the walkway. Segregation of personnel from high-pressure hoses needs to be considered in the design process.”
Other recommendations included ensuring the design of hose and pipe layouts eliminated contact and rubbing, and the regular inspection of high-pressure hoses for wear, abrasion and security of mounting.
It also recommended that hose and cable layout be considered in introduction-to-site inspections for new equipment.
Last year CMS Insurance revealed 62% of longwall hydraulic incidents in the previous eight years had been caused by hose or fitting failures and resulted in 159 injuries.