A bunch-blasting method in which 6 to 15 fuses, cut to respective lengths 2 in (5.1 cm) longer than required, are tied together near one end by two ravelings of fuse spaced about 120 5 to 6 in (12.7 to 15.2 cm) apart. A special cutter cuts the fuses off evenly between the two ties, leaving the fuses tied together and offering a smooth face of cut ends. Another bunch is made from the fuses of the remaining holes in the round. By using a short notched fuse as a spitter, the flame is directed against the cut end of one bunch of fuses. As soon as this bunch ignites, it is held close to the face of the second bunch, moving slowly to contact all fuses with the flame from the first bunch. Bunches should be held at least 6 in back from the end to avoid burning the hands. By this method, all the holes of a round are fired in only two groups and by one spitter.
- 품사: noun
- 분야/도메인: 광업
- 카테고리: 일반 광산; Mineral mining
- Government Agency: USBM
작성자
- ed.young
- 100% positive feedback
(Milwaukee, United States)