| 摘要 |
FIELD: mining engineering. ^ SUBSTANCE: bullet consists of external pulplifting pipe section 1 fitted with seal assemblers and inner water-and air delivering pipes 2 and 4, which upper ends are output from pulplifting pipes, lower end of water delivering pipe is fitted with checker 3, and lower end of air delivering pipe is fixed with sprayer 5. Inside pulplifting and air delivering pipes addition sectional pipe is installed 6 for delivering of warmed water and steam for defrostation of formations, which ends are derived beyond pulplifting pipe. ^ EFFECT: effectiveness improvement of excavation and working of frozen sedimentary strata. ^ 5 cl, 3 dwg, 1 ex |
