ROOF BOLT LOCKED BY FIRING Russian patent published in 2012 - IPC E21D21/00 

FIELD: mining.

SUBSTANCE: roof bolt locked by firing consists of two interconnected pipe pieces and guiding element with oval bottom and unit with ideal cable attached at the oval bottom of guiding element. At the areas of pipe pieces connection one pipe piece has internal cone, the other - external cone that are interconnected by means of external cone installation into the internal one. Along the length of tubular anchor at the cylindrical areas of pipe pieces there are "П"-shaped slots cut with the possibility to bend the "tongues" of "П"-shaped slots in the opposite directions under gas pressure at explosion of detonating cord.

EFFECT: increase of resistance of underground mine workings.

7 dwg