Home/Volume-1/Stowing Practice Volume-1 Stowing Practice Admin02/08/20240 29 Less than a minute Report a question What's wrong with this question? You cannot submit an empty report. Please add some details. 0% Stowing Practice Stowing Practice 1 / 31 1. With hydraulic sand stowing of the goaf the subsidence can be reduced to about ....of the amount caused by caving? 2-Jan 3-Jan 4-Jan 5-Jan 2 / 31 2. For deeper mine the sand:water ratio in sand stowing is? 1:1 1:3 3:1 1:1.3 3 / 31 3. The required water for 1 te of sand in hydraulic sand stowing? 800 liters 900 liters 1100 liters 1300 liters 4 / 31 4. Which portion of the pipe is damaged more in sand stowing? upper portion middle portion 2/3 from the top lower portion 5 / 31 5. The stowing efficiency in Mechanical sand stowing? 50% 73% 60% 70% 6 / 31 6. The line of extraction best suited for hydraulic sand stowing is? step diagonal diagonal 45 deg parallel diagonal 60 deg 7 / 31 7. The stowing efficiency in pneumatic sand stowing? 50% 73% 60% 70% 8 / 31 8. The angle of draw in Indian coal fields? up to 25 deg up to 35 deg up to 40 deg up to 45 deg 9 / 31 9. In sand stowing incorrect profile will affect..? cavitation wear on pipes setup pulsation jamming 10 / 31 10. The face must advance by approximately a distance of ....times the depth of the seam for the full subsidence to take place? 1.4 1.8 2.5 3 11 / 31 11. The sand input to the bunker is calculated by? venturimeter kentmeter lea recorder none of the above 12 / 31 12. In hydraulic sand stowing the operations are conducted such that not more than .....sq.m of roof area is exposed in any working area at a time and not more than .... such places are left unstowed? 60;1 70;2 80;1 80;2 13 / 31 13. The upper portion of the sand stowing pipe is generally changed after the transport of ....lac ton of sand? 2-Jan 4-Feb 6-Apr 8-Jun 14 / 31 14. The stowing efficiency in hydraulic sand stowing? 60% 70% 50% 73% 15 / 31 15. The discharge velocity of the sand in pneumatic sand stowing? 2 m/s 10 m/s 15 m/s 20 m/s 16 / 31 16. There was no movement at the surface until the face advances up to....m? 15m 22m 30m 35m 17 / 31 17. Hydraulic stowing is not successful where the seam is less than ...m depth and flatter than ...deg? 200 ; 5 100 ; 5 100 ; 10 200 ; 10 18 / 31 18. The stowing rate in hydraulic sand stowing is? 60-80 tph 80-100 tph 100-120 tph 120-140 tph 19 / 31 19. The life of the M.S pipe used in sand stowing is......lac ton of sand? 4 6 8 10 20 / 31 20. The stowing rate in Mechanical sand stowing? 50-60 tph 60-70 tph 70-80 tph 80-90 tph 21 / 31 21. The angle of inclination from vertical of the line connecting the edge of the workings and the edge of the subsidence area is called? Angle of fracture Angle of draw Breaking angle hade 22 / 31 22. The min velocity of the slurry in the pipe should be.....? 1 m/s 2 m/s 3 m/s 4m/s 23 / 31 23. In hydraulic sand stowing the throw of the sand without nozzle is ...m and with nozzle is ...m? 2 ; 6 3 ; 7 4 ; 8 5 ; 9 24 / 31 24. In sand stowing high local velocity of sand results in..? cavitation wear on pipes setup pulsation jamming 25 / 31 25. In sand stowing generally the sand required for one te coal extraction in a virgin area? 1.3 te 2 te 2.5 te 3 te 26 / 31 26. The stowing efficiency in hand packing is? 50% 73% 60% 70% 27 / 31 27. The size of the largest particle of the sand does not exceed if the dia of the pipe is D is? 1/2 of D 1/3 of D 1/1.5 of D D 28 / 31 28. In hydraulic sand stowing the pipe end should be away from the dip of the boxing is? 5 m 6.5m 7.5 m 9m 29 / 31 29. In hydraulic sand stowing the H/L ratio for a reasonably good stowing rate? 1:05 1:06 7:01 1:07 30 / 31 30. To stop the stowing which is done to avoid the jamming of the pipe? water should be stopped first sand should be stopped first both should be stopped at a time none of the above 31 / 31 31. If the full subsidence occurs at more than one point then the subsidence is called? critical subsidence subcritical subsidence supercritical subsidence trough subsidence Your score is The average score is 51% LinkedIn Facebook Twitter 0% Admin02/08/20240 29 Less than a minute
