BOLT UP CYCLE
The bolting up cycle is the first major procedure in the recovery of the longwall. The purpose of the bolting up cycle is to provide a safe working environment for the recovery of equipment by providing support to the longwall face. Support is provided to the roof, face, maingate and tailgate.
Support to the roof is usually provided in the form of “w” straps with meshing on the face to prevent any falls from the face. The amount and type of support that is used at each mine will depend upon the conditions at each mine. What works for one mine may not be suitable for another.
The bolting up cycle commences approximately 7 – 10 metres from the final position of the longwall position. This distance will vary from mine to mine. The whole bolt up cycle can take up to 10 days to reach the final position. Prior to the support cycle, it is necessary to straighten up the face using a straight line and have survey marks measured out for the benefit of the longwall operators.
The following sequence that will be described was used at South Bulli Colliery (Now Bellambi West Colliery) 1996 (??). Prior to support cycle the faceline is straightened at 7.0 metres from final position using a stringline.