Procedure for sealing impregnation bore hole by cementation - cement solution is pumped through and round probe with expandable sections

摘要

Procedure for sealing by cementation bore holes during impregnation of coal seams with water by probes with sections expanding by an inner pressure by which two sections of a probe consisting of three sections are inserted in the bore hole. Subsequently, the ring space between the centre section and the bore hole and an attached steel tube of smaller diameter than the centre section are filled with pressurised water. After depressurising of the ring space at the open end of the end bore section the probe is inserted round the steel tube in the bore hole. The end section is connected to a supply of pressurised water and to a supply of cement solution, and is pressed against the wall of the bore hole, and the cement solution is pumped in the bore hole section surrounding the probe centre section through a ring space surrounding the steel tube. When the cement solution is set the end probe section is depressurised and pulled out from the bore hole.