E/MJ : engineering and mining journal . y exploding other holes. Delayed fuses were usedand the holes charged with eight sticks of 80 per centRed Cross gelatine, the detonator being placed in thefourth stick from the bottom. This arrangement is con-trary to the rule for placing the detonator, but owing to the fact that the holes are close together, the collaroften breaks prematurely and tears out the detonatorsthat have not been exploded. When this happens someof the holes do not explode and too much burden isplaced on other holes. No cut failed to be pulled clean, and not one steelshaft set w
E/MJ : engineering and mining journal . y exploding other holes. Delayed fuses were usedand the holes charged with eight sticks of 80 per centRed Cross gelatine, the detonator being placed in thefourth stick from the bottom. This arrangement is con-trary to the rule for placing the detonator, but owing to the fact that the holes are close together, the collaroften breaks prematurely and tears out the detonatorsthat have not been exploded. When this happens someof the holes do not explode and too much burden isplaced on other holes. No cut failed to be pulled clean, and not one steelshaft set was bent, although the sets were kept withinfifteen to twenty feet of the bottom. The blasts weretimed so close together that the effect was to blend theconcussion in one slow, rattling blast. 10 9 8 7 1 2 3 4 5 6 4 4 ^4 4 4 • B 4 • 4 .4 • ^4 ^4 ^3 ^3 1 • _,3,1 .3^1 3 • 1 • B .3J ,3J ^3 3 • ,3J m ? Z ,8 2 • 6 • 2 • • 2 • t .« 5 • 5 • 5 • 5 • 5 • ^5 ^5 ^5 J 5 • Plan(prilling and Blasting) .-abouf 48°. Vertical Section OKDKH FOJ^LOWKD \.i BLASTING MACHINE-DRILLEDROUNDS AT PABST H SHAFT After blasting, the muck was hoisted in two buckets, provided with special guides. At thetrestle landing the buckets were dumped while hangingstraight on the cable, the rock falling on an inclinedshaft cover. This sloping cover was hinged, providedVkith high sides that formed a chute, and was swung inand out of position by means of air-operated complete cycle of work in sinking was as follows: REQiaRKD PER CYCLE OF WORK IN SINKING PABSTH SHAFT Til].I-, Operation Hours Take down material and drill entire cut 6,0 Charge holes (first blast) Remove material and blast 1-0 Blow smoke , Muck biast Charge second blast and fire Blow Muck second blast HoialinE water with bucket, per day Timbering, per set Cuttincj and blasting hitches Installing bearers The shaft sets extending thro
Size: 2286px × 1093px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bo, bookcentury1900, bookdecade1910, booksubjectmineralindustries
