Method of Forming a Cutting Cavity by Charges with a Cumulative Effect

摘要

The object of the invention is a method of forming a cutting cavity by charges of cumulative action. To increase the efficiency of the blast hole and to lower the expenditure of explosives, the blast holes for the cumulative charges are arranged more or less in a circle, and more or less in the center there is located the blast hole for the regular charge. The cumulative charges in the blast holes are mainly arranged from the coal face to the middle of the length of the blast hole, and the regular charge from the middle up to the mouth of the blast hole. The cumulative charges are exploded at the same time and with a delay with relation to the explosion of the center blast hole.