The innovation received the commended award at this year's NSW Minerals Council Mine Safety Innovation awards.
The recovery of longwall roof supports during relocation requires the use of temporary hoses (wander leads or whip hoses) to supply hydraulic power to the support being removed.
During removal, hydraulic pressure to the support must be isolated and any residual hydraulic energy in the support dissipated prior to the hydraulic supply being removed. Currently this process is done using separate in-line valves and tee pieces in the whip hoses.
According to United, the problem with the current method is there is a limited means of locking the isolation handles during the process. Also, there are no means of ensuring the isolation/dissipation sequence is carried out correctly.
“The present system relies on competent personnel to ensure valves are turned on and off in the correct order. This correct sequence of valve operation is essential to guarantee that the residual pressure is dissipated in a controlled manner and the return side of the hydraulic circuit is not inadvertently pressurised,” United said in its entry.
To combat this risk, United developed a longwall support recovery pressure release/isolation valve which provides a lockable isolation and a simple mechanical interlock to ensure the correct isolation sequence is carried out.
“The valve is simple and compact in design and effectively manages two of the major identified risks in the longwall support recovery process,” United said.
Watch out for an article on the NSW Minerals Council Mine Safety Innovation awards winner in the June edition of Australian Longwall Magazine, hitting desks later this month.
