SHORTENED MONOLITHIC STEMMING PLUG Russian patent published in 2008 - IPC F42D1/08 

FIELD: blasting.

SUBSTANCE: invention relates to the field of drilling and blasting in hard rock quarries and may be applied in various industries where blasting in rock masses is used. A shortened monolithic stemming plug is made of a concrete mixture. The bottom portion of the stemming plug receives a hollow conical pressboard or plastic element that is mounted with its tip pointing upwards and occupies up to a half of the stemming plug height. The conical element is mounted onto a foam polystyrene or foam plastic pack being placed between an explosive charge and the monolithic stemming plug.

EFFECT: reducing the volume of concrete mixture required for making a monolithic concrete stemming plug.

2 dwg