| 摘要 |
FIELD: mining. ^ SUBSTANCE: invention refers to mining and is used for generating directional cavities by hydro-break of rock through borehole in order to sheet difficult- to-destroy roof, to degas coal bed, and to control deflected mode of rock massif in vicinity of mine opening. The facility consists of a hollow cylinder case, of a spacing component in form of a collet with cross fastening wedges on external surfaces of its blades and with a base facing the base of the case; further the facility consists of an elastic sealing bushing put on the collet. The case and the collet are made in form of cartridges and are engaged with their bases with a common central opening by means of a screw pair; the bushing with circular external lugs on ends passes through this opening; the first lug limits lengthwise travel of the bushing relative to the case, while the second lug does the same relative to the collet. Inside the bushing there is installed a plug destructed under pressure of working agent, while on free end of the case there is made thread for connection to a high pressure pipe string. ^ EFFECT: increased efficiency of facility due to lowered labour intensiveness at its installation and operation; and facilitating required force to hold down facility to bottomhole of borehole without additional equipment. ^ 7 cl, 4 dwg |
