METHOD OF GOPHER HOLE FORMATION OF SHORT COMBINED STEMMING OF BLAST HOLES AND DEVICE FOR ITS IMPLEMENTATION Russian patent published in 2015 - IPC F42D1/08 

FIELD: mining.

SUBSTANCE: method of gopher hole layer-by-layer formation of short combined stemming includes the formation of the lower fill part from inert fine materials with the height of 1-2 diameters above air interval and formation of upper combined part filled with from stone material elements to the height of 0.2-0.6 well diameters. The transport container with stone material inserted into a soft bag is placed into the bearing funnel of the gopher hole and the soft bag is released which smoothly slides off along the pulled gopher hole down to the layer of inert fine material. The transport container is removed from the bearing funnel and again filled up with the layer of inert fine material to the height of 0.5-1.5 of the well diameter. Again the stone material is unloaded from the transport container. The process is repeated until full formation of the combined stemming. The transport container is made of metal or plastics in the form of the top ring fitted with bearing cord with the size 0.8-0.9 of internal diameter of the bearing funnel of the gopher hole where bars are evenly fixed with the step excluding loss of small pieces of stone material. The transport container is inserted into the soft bag 20-30% larger then the well diameter.

EFFECT: invention allows to improve efficiency of fixing of products of detonation in the charging cavity.

2 cl, 4 dwg