Deep-hole infusion method for coal seams - has forward and rear inflatable bladders with end ball valve and release connection between

摘要

Deephole infusion method for coal mining embodies a forward (1) and rear (2) bladder connected up by pipes (4) and held at required spacing. A ball valve (6) at the bottom hole ensures that both infusion sondes provide a sealing effect at identical pressures. The releasable coupling (2) between the two bladders (1, 3) has an opposed thread so that when all other components are retrieved, this thread operates to leave the forward bladder within the hole. The sense of the other connections ensures that the remaining components are twisted round and withdrawn together.