In Belgorod, engineers from "Evoblast Engineering" patented an innovative design for a sectional charge for contour blasting. This device is designed to simplify installation, increase the reliability of connecting individual parts, and minimize rock damage outside the specified contour.
The new design is intended for the mining industry and special blasting operations. It consists of a column of interconnected sections made of a polymer pipe with an emulsion explosive placed inside. The external elements of the structure hold the sections inside the borehole and prevent them from shifting relative to the specified position.
The key change concerns the connection of the sections. The authors used a design that is called a "herringbone" type connection in the patent. One end of the section has a conical centralizer and annular elements, while the second is made in the form of a mating conical bell. The scheme should facilitate the assembly of a long column and provide a more rigid connection of adjacent sections.
The design also includes channels for air removal from the joint area. According to the authors, this reduces the likelihood of air gaps between adjacent sections of the charge and increases the reliability of detonation transmission throughout the column.
Another element is a visual mark that allows controlling the correctness of the section connection. The side stops are removable and equipped with radially arranged spacers. Their task is to hold the charge in the required position inside the borehole.
The development is designed not only for vertical, but also for horizontal and inclined boreholes.